RULES FOR LIFTING APPLIANCES OF SHIPS AND OFFSHORE INSTALLATIONS

Transcription

1 CHINA CLASSIFICATION SOCIETY RULES FOR LIFTING APPLIANCES OF SHIPS AND OFFSHORE INSTALLATIONS 2007 Effective from April BeiJing

2 CONTENTS CHAPTER 1 SURVEYS AND CERTIFICATION APPLICATION DEFINITIONS PLANS AND DOCUMENTS CLASS NOTATIONS SURVEYS CERTIFICATION...9 CHAPTER 2 DERRICK SYSTEMS CALCULATING CONDITIONS AND LOADS SLEWING DERRICK AND UNION PURCHASE RIGS DERRICK BOOMS MAST AND DERRICK POST...17 CHAPTER 3 CRANES, LIFTS AND RAMPS GENERAL PROVISIONS SHIPBOARD CRANES OFFSHORE CRANES SUBMERSIBLE HANDLING SYSTEMS HEAVY LIFT CRANES CRANE PEDESTALS CARGO AND VEHICLE LIFTS VEHICLE RAMPS PASSENGER AND CREW LIFTS STRENGTH OF SUPPORTING STRUCTURE OF CRANE PEDESTALS...55 CHAPTER 4 MACHINERY, ELECTRICAL INSTALLATIONS AND CONTROL ENGINEERING SYSTEMS GENERAL PROVISIONS CONTROLS AND SAFEGUARDS OF LIFTS FOR PASSENGERS AND CREW CONTROLS AND SAFEGUARDS OF LIFTING APPLIANCES FOR CARGO HANDLING...61 CHAPTER 5 FITTINGS, LOOSE GEAR AND ROPES GENERAL PROVISIONS FITTINGS LOOSE GEAR ROPES...65 CHAPTER 6 MATERIALS AND WELDING GENERAL PROVISIONS ROLLED STEELS STEEL FORGINGS

3 6.4 STEEL CASTINGS WELDING...70 CHAPTER 7 TESTING GENERAL PROVISIONS TESTING OF LOOSE GEAR BREAKING TESTS OF ROPES TESTING OF LIFTING APPLIANCES RETESTING OF LIFTING APPLIANCES...75 CHAPTER 8 MARKING MARKING OF LOOSE GEAR MARKING OF LIFTING APPLIANCES...76 APPENDIX 1 CRITICAL STRESS FOR VARIOUS MEMBERS SUBJECTED TO COMPRESSION...78 APPENDIX 2 DERRICK FITTINGS...84 APPENDIX 3 REGISTER OF LIFTING APPLIANCES AND CARGO HANDLING GEAR...97 APPENDIX 4 CONDITIONS OF RATIFICATIONS OF ILO CONVENTIONS NO.32 AND NO.152 BY PORT STATE AUTHORITIES

4 CHAPTER 1 SURVEYS AND CERTIFICATION 1.1 APPLICATION The Rules are applicable to the following lifting appliances used on board ships and offshore installations: (1) derrick rigs, including derrick cranes; (2) cranes; (3) submersible handling systems; (4) passenger and crew lifts; (5) cargo and vehicle lifts (where the certificate for lifting appliances is necessarily to be issued) and vehicle ramps (where the certificate for lifting appliances is necessarily to be issued) Lifting appliances other than those described in of this Chapter may be considered in accordance with the principles of the Rules The materials and the welding for lifting appliances are to comply with the applicable requirements of CCS Rules for Materials and Welding The relevant standards acceptable to CCS may be used as the equivalent to the requirements of the Rules, provided all the forces resulting from the intended mode of operation for the lifting appliances are taken into account The standards recognized by CCS for fittings and loose gear will in general be accepted as the equivalent to the requirements of the Rules Alternative arrangements or fittings and loose gear which are equivalent to those required by the Rules may be used For novel lifting appliances or lifting appliances with special functions, additional plans and documents are to be submitted in addition to those normally required. 1.2 DEFINITIONS For the purpose of the Rules: (1) Lifting appliances mean derrick rigs, derrick cranes, cranes, lifts and ramps installed on board ships or offshore installations, as appropriate, for the purpose of handling or transferring cargo, equipment, goods, or persons, etc. (2) Light derricks mean the derricks or derrick cranes of which the safe working load is equal to or less than 98 kn. (3) Heavy derricks mean the derricks or derrick cranes of which the safe working load is more than 98 kn. (4) Derrick cranes mean the derricks as rigged with twin span tackles and may be handled under loaded condition by one operator to complete hoisting, slewing and lifting operations. (5) Loose gear means the gear which is not permanently attached to the lifting appliances, such as chains, triangle eyeplates, hooks, blocks, shackles, swivels, sockets, preventer guys with patent clips and rigging screws, etc. Lifting beams, spreaders, frames and similar items of equipment are also considered as loose gear. (6) Fittings mean fittings which are permanently attached to the derrick booms, masts or derrick posts, decks, superstructures or other structures such as eyeplates, derrick heel assemblies, gooseneck bearings including gooseneck pipes, derrick bands and built-in sheaves, etc. (7) Safe Working Load (SWL): 1 Safe working load of a lifting appliance means the maximum static load the appliance is certified to be capable of sustaining whilst correctly rigged under the design operation. 2 Safe working load of loose gear means the maximum load for which the gear has been designed and tested. This load is not to be less than the maximum load to which the gear will be subjected when the lifting appliance is operating at its SWL. --

5 (8) Standard service conditions are the conditions under which the SWL of a lifting appliance is ascertained. It is to include all of the following conditions: 1 the angle of heel not exceeding 5 and a trim of 2 during the operation of the appliance; 2 the appliance being operated in harbour; 3 the appliance being operated at a wind speed not exceeding 20 m/s and a corresponding wind pressure not exceeding 250 Pa; 4 the motion of lifting load being free from any external conditions; 5 the nature of the lifting operations in terms of their frequency and dynamic characteristics being compatible with the load of factor permitted in the Rules for the appliances concerned. (9) Specified service conditions mean the operating conditions for the design of an appliance, which are more onerous than those as described in the standard service condition in virtue of any of the following operational and environmental conditions being applicable: 1 the angle of heel and/or trim of a ship exceeding those as specified in the standard service conditions; 2 the appliance being operated in an unsheltered area; 3 the appliance being operated at a wind speed exceeding 20 m/s and a corresponding wind pressure exceeding 250 Pa; 4 the load not being at rest at the time when the appliance commences the lift; 5 the motion of lifting load not being free from the external constraints; 6 the nature of the lifting operation in terms of their frequency and dynamic characteristics not being compatible with the factor load permitted in the Rules for the appliances concerned. (10) Factor load means the loads (excluding wind load) to be considered in designing a lifting appliance, expressed as follows: factor load = live load duty factor dynamic factor (11) Live load is the sum of the safe working load (SWL) of an appliance and the static weight of any component of the appliance which is directly connected to, and undergoes the same motion as, the safe working load during the lifting operation. (12) Duty factor is a factor which makes allowances for the frequency and state of loading for which a lifting appliance is to be considered in design. (13) Dynamic factor is a factor which takes account of all the dynamic effects of the appliance arising from its lifting operation, and by which the live load is multiplied to represent the load for all dynamic effects on the system. (14) Dead load is the self-weight of any component of the lifting appliance which is not included in the live load. (15) Design stress is the maximum stress permitted in the Rules to which any component part of a lifting appliance may be subjected when the appliance is lifting its safe working load (SWL), that is, when the appliance is subjected to the factor load plus the specified lateral and wind loads. (16) General examination is to take the form of a visual inspection of the lifting appliances, which is to be supported by other means as necessary and carried out so far as practical to achieve a sound view on components in question. For this purpose, components or parts are to be dismantled for more thorough examination where considered necessary. (17) External examination is to take the form of a visual inspection of the lifting appliances by checking for deformation or other defects of components, such as chafe or excessive wear and corrosion. 1.3 PLANS AND DOCUMENTS In the case of derrick rigs the following plans and documents are to be submitted for approval: (1) a rigging (including derrick cranes) plan, indicating the layout of the light derricks, heavy derricks and union purchase and the portions of individual items of loose gear; (2) force diagram of derrick rigs and in the case of union purchase rigs also the working range and specified data; (3) scantling plans of masts, derrick posts and stays where fitted; (4) scantling plans of derrick booms including their head and heel fittings; --

6 (5) details of gooseneck bearing bracket, gooseneck pins, span eyeplates, guy eyeplates and similar fittings; where recognized international standards or national standards appropriate are in use, only a list of fittings indicating material, safe working loads and the standards with which the fittings have been manufactured in compliance is to be submitted; (6) the material specification for steels including grades of steel, welding consumable and type and size of welds to be used in the mast, derrick boom and associated fittings as shown in (3), (4) and (5) above; (7) strength and/or stability calculations for masts, derrick posts and stays (if fitted) and derrick booms The following plans and documents for derrick rigs are to be submitted for information: (1) a list of blocks, chains, shackles, hooks, swivels and other items of loose gear indicating material, safe working load, proof load and the standards under which they have been manufactured; (2) a list of wire and fibre ropes indicating size, construction, finish and certified breaking loads, normal tensile strength being indicated for wire ropes In the case of crane systems, the following plans and documents are to be submitted for approval: (1) general arrangement of crane, including specification of principal operational parameters; (2) force analysis for the crane system; (3) the layout of lifting, luffing, slewing and travelling mechanisms, including the arrangement and functions of overload protection, overmoment protection and various limit switches; (4) strength calculations of main items, clearly indicating the design basis, operating criteria, rated capacity, weights and centres of gravity of the crane parts and relevant national standards; (5) stability calculation of crane, as applicable; (6) structural plans of all main components comprising the crane including jib, tower, platform, gantry, logies, slewing ring, pedestals, rails, stowage arrangement, indicating their structures, scantlings and grades of steel, welding consumable and type and size of welds The following plans and documents for crane systems are to be submitted for information: (1) details of sheaves, axles, pivot pins, wheels, spreader beams, slewing ring, slewing ring bolts and similar items and the specification of the grade of steel to be used; (2) details of blocks, hooks, swivels, lifting beams, spreaders, frames and other items of loose gear, indicating material, safe working load (SWL), proof load and the standard to which they have been manufactured; (3) the size, construction, finish and certified breaking loads of and normal tensile strength for wire ropes to be used In the case of lifts and ramps, the following plans and documents are to be submitted for approval: (1) design specifications, including materials to be used; (2) all main structural plans; (3) details of sheaves and sheave supports; (4) calculation clearly indicating the ratings, vehicle loads, wheel centres, tyre prints, working range and angles, weights and centres of gravity of component parts; (5) reeling arrangements; (6) the size, construction, finish and certified breaking loads of wire ropes and chains; (7) typical layout, including the details of lift car construction and guide rails, as applicable; (8) typical entrances, as applicable; (9) landing door fire test specification in the lift trunk, as applicable; (10) arrangement and details of the lift trunk including safety devices, as applicable The following plans and documents with respect to machinery, electrical and control systems are to be submitted for approval: (1) general arrangement of the control cabinet(s) and/or control station; (2) arrangement of power switchboard and its circuit diagrams; (3) diagrams of electrical circuit system indicating the specifications of equipment and cables, grade of insulation, rated current, types of various electric protections and their rated capacity and manufacturers; (4) short circuit current calculations for the bus-bar of the main and auxiliary switchboards and the output ends of transformers; --

7 (5) schematic diagrams of control circuits, interlocks and alarm system, including hydraulic, pneumatic and electric power; (6) details of safety devices, including securing and latching arrangement; (7) particulars of hydraulic rams and operating systems, if fitted The following plans and documents for machinery, electrical and control systems are to be submitted for information: (1) specifications for the operation and application; (2) general arrangement of motor room including their power units and specifications; (3) general arrangement of hoisting, luffing, slewing and travelling machanisms together with the technical instruction of these components The strengthening plans for connection of the lifting appliance to hull structure are to be submitted for approval. 1.4 CLASS NOTATIONS Upon satisfactory completion of all tests and surveys of the lifting appliances for classification purposes and issue of all the appropriate test and survey certificates and the Register of Lifting Appliances and Cargo Handling Gear in accordance with the Rules, the Surveyor is to recommended the Headquarters of CCS to assign the class notation Lifting Appliance and enter this in the Interim Classification Certificate for Hull The Surveyor is to report the survey in a form of survey report (Form CG) to the Headquarters of CCS, together with copies of all issued certificates and documents The class notation will be formally assigned and entered in the Classification Certificate for Hull and in related documents by CCS after approval. 1.5 SURVEYS General requirements The lifting appliances are to be subject to an initial survey before being taken into use. Periodical tests and surveys are to be carried out after the lifting appliances being taken into use All loose gear prior to initial use for the lifting appliances, as well as the replaced or repaired components which affect the strength when in use, are to be proof tested and thoroughly examined Where a major accident occurs or a major defect is found, and the components to be replaced or repaired affect the strength, the master or the owner is to report to CCS so that the related lifting appliances can be surveyed in time The testing, proof test, survey and examination as stated in this Chapter are to be carried out in accordance with CCS rules or equivalent provisions recognized by CCS The loose gear and wire ropes, other than those having been satisfactorily examined within the last three months, are to be inspected by the responsible persons onboard the ship before each use. Ropes with broken wires are to be inspected at least once a month Types of survey for lifting appliances are as follows: (1) initial survey; (2) annual survey; (3) renewal survey (i.e. quadrennial thorough survey); (4) damage and repair surveys; (5) postponement survey The above-mentioned surveys are to be carried out in accordance with the requirements of this Section Other requirements --

8 (1) Where the lifting appliances are laid up or repaired for more than 12 months, an inspection is to be carried out before they are re-taken into use. The extent of the test and examination is to be determined depending on the types of survey to be carried out in the laid-up or repair period. For example, if the renewal survey and load test are due, the testing and survey are to be completed and the certificate is to be issued accordingly, and the new period of the renewal survey is to start from the date of completion of such testing and survey. (2) In view of the attitude that some National Authorities adopt with respect to the competence and independence of the person carrying out the survey, such as the ship s officer, it is recommended that only the CCS Surveyor carry out the survey and issue certificates if delays and inconvenience to the owner are to be avoided. (3) Other surveys not previously specified, if requested by the owner, will be specially considered by CCS, but the separate instructions are to be supplied by the owner. (4) Any item such as a mast or crane pedestal, which is permanently fitted to a ship s structure and which is designed to support a lifting appliance, does constitute part of the classed ship and is to comply with the appropriate classification requirements, even where the lifting appliance itself is not classed or certified by CCS Initial surveys An initial survey is to consist of: (1) examining plans and documents to be submitted by the applicant in triplicate for approval and information as required by 1.3, except for the manufactures having been approved by CCS; (2) checking the approved design drawings and technical documents of the lifting appliance; (3) examining that the arrangement, components, scantlings, devices, materials, welding and workmanship of the lifting appliance are to comply with the approved plans and documents; (4) examining the fittings and loose gear of the lifting appliance one by one together with their certificates and checking the marks; (5) thoroughly examining the lifting appliance during installation and testing to be carried out after installation in accordance with Chapter 6 so as to confirm that all equipment operates effectively and safely, and that any cutouts, controls and similar devices function correctly. After testing, the installation, including the supporting structure, is to be examined to ensure that no deformation or distortion has occurred. Works testing of cranes cannot be accepted as an alternative to onboard testing After a satisfactory initial survey, the related certificates as specified in 1.6 are to be issued, and the Register of Lifting Appliances and Cargo Handling Gear is to be endorsed Initial surveys of existing installations on board ships may be carried out in accordance with the following requirements: (1) The arrangements, scantlings, calculations, instructions and relevant information of the installation are to be submitted to CCS for examination. (2) All loose gear for the installation is to be examined to verify that the item is individually marked and certified. Where certificates are missing, items are to be proof tested and remarked. (3) A thorough survey of the installation and supporting structure is to be carried out equivalent to a renewal survey, and load testing is to be carried out as required by Chapter 6. (4) After a satisfactory survey, the related certificates as specified in 1.6 are to be issued, and the Register of Lifting Appliances and Cargo Handling Gear is to be endorsed The lifting appliances on board the ships classed with one IACS member, when required for the transfer of class to CCS, are to be surveyed and certified as follows: (1) Where an existing ship is at the time of a renewal survey, such testing and survey are to be carried out in accordance with the requirements for renewal surveys of this Chapter. After a satisfactory survey, the testing and survey certificates are to be issued, and a new Register of Lifting Appliances and Cargo Handling Gear is to be endorsed for the renewal survey. (2) Where an existing ship is at the time of an annual survey, such testing and survey are to be carried out in accordance with the requirements for annual surveys of this Chapter. After a satisfactory survey, a new Register of Lifting Appliances and Cargo Handling Gear is to be issued and endorsed for the annual survey, and the various testing and survey certificates of the existing ship are to be attached to the new Register. (3) The register book on board an existing ship as required by a certain port State authority may also be endorsed if so requested by the owner and after a satisfactory survey, provided that the requirements of the flag State are complied with. --

9 The lifting appliances on board the ships classed with non-iacs members are, when CCS class is requested, generally to be surveyed in accordance with The lifting appliances intended for classification, which are found to comply with the abovementioned requirements upon an initial survey, will be assigned the notation Lifting Appliance. For the purpose of maintenance of classification, the owners are to make application in accordance with 1.5 for the periodical surveys and the issue of certificates carried out by CCS Surveyors Annual surveys An annual survey of the following items is to be carried out at intervals not exceeding 12 months after the initial survey or the renewal survey: (1) The derrick booms together with fittings attached to the booms, masts or derrick posts, and deck are to be externally examined as detailed in Table a; (2) The loose gear is to be thoroughly examined as detailed in Table a; (3) The wire ropes are to be externally examined as detailed in Table a; (4) The winches, cranes, cargo lifts and vehicle ramps are to be thoroughly examined as detailed in Table b. Items and Description for Survey of Derrick Systems Table a No. Item Derrick systems 1 Derrick boom and mast fittings (1) Examine lugs, etc., at derrick head and mast head. (2) Examine goosenecks and heel pins for deformation, wear, scoring or other defects. (3) Examine independent heel block anchorages 2 Fittings on deck Examine deck eyeplates, wire rope stoppers, etc. 3 Derrick booms and masts (1) Examine for corrosion (where this is suspected, paint to be removed as necessary). Special attention is to be paid to the part of the boom which comes into contact with the crutch or housing. If considered necessary, thickness is to be checked. (2) Examine for scars or dents and check that boom is not bent (where this is suspected, to be removed for measurement). (3) Ensure that the head and heel fittings are in good working order. Where considered necessary, boom is to be manoeuvred through all its working positions 4 Blocks (including guy blocks) (1) Blocks to be examined. Particular attention is to be paid to sheave rotation, efficient lubrication and verification that there is no sign of excessive wear on the pin or scoring of the rope groove. If considered necessary, to be stripped down. (2) Verify that blocks are of the appropriate safe working load for the position in which they are rigged 5 Shackles ( including guy shackles), links, rings, hooks, triangle plates, etc. 6 Wire ropes 7 Span chains 8 Re-test (1) Examine and check for wear, deformation or other defects. Items are to be sufficiently free from paint, grease, scale, etc., to enable a proper examination to be made. (2) Verify that items are of the appropriate safe working load for the position in which they are rigged Examine wire ropes, with particular attention to broken wires at ferrule connections or corroded wires Examine the chain which is to be sufficiently free from paint, grease, scale, etc., to enable a satisfactory examination to be made. Check for deformation, wear or other defects (1) Where certificates for the repaired or renewed item are not available, the derrick is to be re-tested. (2) Items to be load tested if repairs have been carried out which affect the strength --

10 Items and Description for Survey of Cranes, Lifts and Ramps No. Item Cranes, lifts and ramps 1 2 Arrangement Fixed sheaves, blocks, axle pins and housings Table b Check reeving arrangement and hoisting block assembly as shown in Cargo Gear Arrangement Plan or manufacturer s manual (1) Determine that the sheaves are free from cracks. Where the design is such as to prevent this examination it may be necessary to dismantle the item. (2) Examine rope groove for scoring. (3) Ensure that all lubrication arrangements are in working order. (4) Check anchorage of fixed axle pins. (5) Check for free rotation of sheave on axle pin. (6) Check for excessive wear of axle pin and sheave bush, which may be dismantled where necessary. (7) Check condition of housing and separation plates 3 Jib heel pins, ramp hinges Check lubrication and ensure that there is no detrimental wear 4 Slewing rings 5 Wire ropes 6 Structure 7 Shackles, rings, hooks, etc. 8 Chains 9 Rope drums Hydraulic cylinders, winches, etc., and attachments Main pivots, slewing bearings, etc. 12 Re-test (1) Check lubrication, ensure tightness of bolts and check that there is no detrimental wear or excessive movement in the ring. (2) Particular attention is to be paid for signs of wear in the inner and outer rings and for signs of wear in the raceways. (3) Additional inspections are to be carried out where these are specified by the crane or slew ring manufacturer (1) Examine entire length of rope. (2) Check for broken, worn or corroded wires. The rope is to be replaced if the number of broken, worn or corroded wires exceeds the limit given in (3) (3) Examine terminal fittings, splices, etc., with particular attention to broken wires at ferrule connections. Any serving on splices is to be removed for the examination. (4) Before re-rigging ensure that the wire rope has been thoroughly lubricated (1) Check all bolts for tightness ensuring that where bolts have been replaced they are of the same type and quality as previously fitted. (2) Examine foundation bolts for signs of corrosion. (3) Check welds for cracks. (4) Examine structure for corrosion, removing paint and carrying out hammer tests as necessary. (5) Check jib, tower, support pedestal, gantry, ramps, rails, etc., for any sign of local indentation or unfairness (1) Thoroughly examine under proper conditions and check for cracks, deformation, wear, wastage or other defects. Items are to be free from paint, grease, scale, etc. (2) If deformation of the shackle is found, and re-setting is carried out, the shackle is to be suitably heat treated and re-tested. (3) If the shackle pin is renewed, the whole shackle is to be re-tested (1) Check for deformation, wear or other defects after removal of all paint, grease, etc. (2) Replaced links are to be of equivalent material and strength to original, and to be suitably heat treated and re-tested (1) Ensure that at least two turns of wire ropes are on the drum in all operating positions. (2) Check that the anchorages of all wire ropes are effective. (3) Check drum for cracks and for defects liable to damage the rope. (4) Check the effective working of any fleeting device fitted (1) Check condition of hydraulic pipes. (2) Check pistons, pivot pins and bearings, etc., for excessive wear and deformation. (3) Ensure that mounting brackets are free from deformation or damage (1) Examine main pivots and bearings to ensure that they operate satisfactorily and are free from excessive play, and that pivot pins do not have excessive wear or deformation. (2) Ensure that lubrication arrangements are in working order (1) Where certificates for the repaired or renewed item are not available, the derrick is to be re-tested. (2) Loose gear is to be load tested if repairs have been carried out which affect the strength. (3) It is essential that the crane is operated at each survey to verify safe and efficient working and to check hoisting, slewing, luffing and travel motions, and the operation of limit switches for over hoisting, over lowering, luffing, slewing and travel --

11 Check the record of use, maintenance and repair of the hoisting machinery, winches, etc., to confirm they are in normal maintenance condition The components as part of submersible handling systems may be surveyed as referred to the requirements as appropriate in After a satisfactory annual survey, the Register of Lifting Appliances and Cargo Handling Gear is to be endorsed Renewal surveys The following items of a renewal survey are to be carried out at 4-yearly intervals after the initial survey or the renewal survey: (1) The derrick booms together with fittings attached to the booms, masts or derrick posts, and deck are to be thoroughly examined as detailed in Table The derrick systems are to be load tested in accordance with Chapter 6. Items and Description for Survey of Derrick Systems Table No. Item Derrick systems 1 errick boom and mast fittings (1) Examine lugs, etc., at derrick head and mast head. (2) Withdraw and thoroughly examine goosenecks, trunnion fittings, etc., together with their pins. (3) Withdraw all other pins and thoroughly examine mast head span swivels, tumblers, etc. (4) Check pins for deformation, wear, scoring or other defects. (5) Examine independent anchorages for heel blocks 2 Fittings on deck Examine deck eyeplates, cleats, wire rope stoppers, etc. 3 Derrick booms and masts 1) Examine for corrosion (where this is suspected, paint to be removed as necessary). Special attention is to be paid to the part of the boom which comes into contact with the crutch or housing. (2) Hammer test boom and, if then considered necessary, check thickness. (3) Examine for scars or dents and check that boom is not bent (where this is suspected, to be removed for measurement) 4 Blocks ( including guy blocks) 5 Shackles (including guy shackles), links, rings, hooks, triangle plates, etc. All sheaves and pins are to be removed. All stress bearing parts of the blocks, including head fittings, are to be thoroughly cleaned (the paint being removed where necessary) and thoroughly examined. The nut or collar of the shank or swivel head fittings is to be examined to ensure that it is securely fastened and free from visible defects. The shank should turn freely by hand and wear is not to be excessive. The shank is to be removed if necessary. Cheek and partition plates are to be examined to ensure they are not buckled, distorted nor worn to sharp edges (1) Check for cracks, deformation, wear, wastage or other defects. Items are to be free from paint, grease, scale, etc. (2) If deformation of the shackle is found, and re-setting is carried out, the shackle pin is to be suitably heat treated. (3) If the shackle pin is renewed, the whole shackle is to be re-tested and certified. (4) Verify that items are of the appropriate safe working load for the position in which they are rigged 6 Wire ropes (1) Examine entire length of rope. The rope is to be cleaned if necessary. (2) Check for broken worn or corroded wires. (3) All ferrule connections are to be examined. (4) Before re-rigging ensure that the wire rope has been thoroughly lubricated 7 Span chains (1) The chain is to be thoroughly examined after removal of all paint, grease, scale, etc. (2) Check for deformation, wear or other defects. If links require renewal the chain is to be suitably heat treated and re-tested. Replaced links are to be of equivalent material and strength to original 8 Re-test Derrick systems are to be load tested at each quadrennial thorough survey --

12 (2) The cranes, lifts, vehicle ramps together with loose gear are to be thoroughly examined in accordance with the relevant requirements of The cranes, lifts and vehicle ramps are to be load tested in accordance with Chapter 6. The test is to demonstrate satisfactory operation, efficiency of overload and weightload indicators, effectiveness of limit switches After a satisfactory renewal survey, the Certificate of Test and Examination of Lifting Appliances or the Certificate of Test and Examination of Derricks Used in Union Purchase, if appropriate, is to be issued, and the Register of Lifting Appliances and Cargo Handling Gear is to be endorsed accordingly Damage and repair surveys The stated cause of the damage of the lifting appliance is to be reported to CCS in time, together with details of the proposed repairs, and the scope of survey is to be necessary for the Surveyor to find the extent of damage and cause Any worn or corroded parts found during the survey are to be replaced or repaired immediately where: (1) the structural member and fittings have a wastage over 10 per cent based on the material thickness, or cracks or permanent deformation; (2) the items of loose gear, such as eyes, links, shanks, straps and hooks, etc., have a wastage over 10 per cent of their original dimensions and a wastage of pins over 6 per cent of their original dimensions, or cracks or permanent deformation, and any breakage or cracks on the sheaves; (3) excessive wear or corrosion or 5 per cent of broken wires in any length of ten times the rope diameter takes place 1 ; (4) the brake liner wears excessively and the fastenings securing the liner expose out in the friction surface; (5) the transmitting gear tooth is broken or its rim, sprocket or hub is cracked Replacement items of loose gear are to be accompanied by a manufacturer s certificate, and the materials used in the repair are to be equivalent to original A load test is to be carried out in accordance with the relevant requirements after completion of repair, and the Certificate of Test and Examination of Lifting Appliances is to be endorsed after satisfactory testing. The Register of Lifting Appliances and Cargo Handling Gear is to be endorsed indicating the extent of the survey even if it was not possible to complete the repairs, and use of the equipment is not allowed until satisfactory completion of repairs and tests After damage and repair surveys, a factual report is to be issued clearly stating: (1) attending persons; (2) the stated cause of the damage (ship s sea protest attached); (3) the extent and nature of the damage found; (4) the extent and nature of repairs carried out and whether the repairs were complete; (5) the test load applied Postponement survey Where requested by the owner, the postponement for renewal survey may be granted but the interval between two consecutive renewal surveys is not to be more than 5 years. Such postponement survey is to be granted by the national authority of the flag State of the ship. The authority is to authorize CCS to carry out the survey The scope of postponement survey is not to be less than that of annual surveys as stated in 1.5.3, so as to confirm that the ship is fit for its intended service and in normal operating conditions After a satisfactory postponement survey, the Register of Lifting Appliances and Cargo Handling Gear is to be endorsed accordingly. 1.6 CERTIFICATION Certificates The following certificates for lifting appliances issued by CCS are based on the standard international forms of certificates approved by the International Labour Office (ILO), and are internationally recognized in respect of the Rules: 1 Refer to ISO 4309: Wire Ropes for Lifting Appliance Code of Practice for Examination and Discard. --

13 (1) Register of Lifting Appliances and Cargo Handling Gear (referred to hereinafter as the Register), Form RLA 2; (2) Certificate of Test and Examination of Lifting Appliances, Form CLA 2; (3) Certificate of Test and Examination of Derricks Used in Union Purchase, Form CUD 2; (4) Certificate of Test and Examination of Loose Gear, Form CLG 2; (5) Certificate of Heat Treatment of Loose Gear Made of Iron, Form CHT 2; (6) Certificate of Test and Examination of Wire Rope, Form CWR 2; (7) Survey Report on Ship's Lifting Appliances, Form CG; (8) Class notation: Lifting Appliance If a national authority requires its own certification to be used, CCS may, where authorized, arrange the issue of these certificates, which may be in addition to CCS certification if so desired by the owner Issue and endorsement of certificates Register of Lifting Appliances and Cargo Handling Gear Following satisfactory completion of all the conditions required for the issue of certification by CCS, the Register of Lifting Appliances and Cargo Handling Gear and the Certificate of Test and Examination of Lifting Appliances, and the equivalent national authority form (if applicable), are to be issued and the appropriate loose gear, rope and appliance test certificates attached. (1) PART I of the Register is for endorsement after completion of the renewal survey, i.e. quadrennial thorough examination, and the annual survey of derrick systems. Column (3) Remarks is generally for the postponement of renewal survey. Column (4) Remarks is specially for recording the damage, repair, re-test and inspection of fittings. (2) PART II of the Register is for endorsement after completion of the annual thorough examination of winches, cranes of derrick systems. Column (3) Remarks is specially for recording the damage, repair, retest and inspection of cranes, winches and accessory gear. A load test at a 4-yearly interval for cranes is also endorsed in column (3) in the case of a postponement survey. (3) PART III of the Register is for endorsement after completion of the annual thorough examination of loose gear made of steel other than those made of iron. Column (3) Remarks is specially for recording the damage, repair, re-test and inspection of loose gear made of steel. (4) PART IV of the Register is for endorsement after completion of the heat treatment of loose gear made of iron. As the loose gear made of iron has not generally been adopted, this PART is seldom used. (5) Where the owner has made an application to stop the use of a lifting appliance, the location and number of such lifting appliance are to be noted in column (3) Remarks of PART I or PART II of the Register, and endorsed. (6) In examination, if any structure, installation or arrangement affecting its safe working condition is found, brief comments and requirements are to be made in the column of remarks of the corresponding PART of the Register, and endorsed Certificate of Test and Examination of Lifting Appliances The certificate applies to all lifting appliances, including derrick systems, cranes, lifts, ramps, etc., and is to be issued after a satisfactory survey and load test. In general, the certificate will be issued after completion of each quadrennial load test and also the test and survey of damage, repair, re-construction and re-use Certificate of Test and Examination of Derricks Used in Union Purchase The certificate applies to derrick systems used in union purchase, and is to be issued after a satisfactory survey and union purchase test according to the relevant requirements. The certificate is to be kept and used together with the Certificate of Test and Examination of Lifting Appliances. The H, X and Y values of the fixed positions of eyeplates for derricks in union purchase as shown on the reverse of the certificate are to be entered according to the design Certificate of Test and Examination of Loose Gear The certificate applies to all loose gear of lifting appliances, and is to be issued after a satisfactory survey and proof test. The technical parameters may be referred to in the approved manufacturer s test certificate. Where all loose gear is made of steel in general use, heat treatment is not necessarily to be made periodically, and the remarks are to be made in the column Description of gear of the certificate. -10-

14 Certificate of Heat Treatment of Loose Gear Made of Iron The certificate applies to all loose gear made of iron of lifting appliances, and is to be issued after a periodical heat treatment. It is recommended that such loose gear made of iron be replaced by that made of steel Certificate of Test and Examination of Wire Rope The certificate applies to wire ropes of lifting appliances, and is to be issued after a satisfactory test and survey. The technical parameters may be referred to in the approved manufacturer s test certificate Certificate of Test and Examination of Fibre Rope The certificate applies to all fibre ropes of lifting appliances, and is to be issued after a satisfactory test and survey. The technical parameters may be referred to in the approved manufacturer s test certificate Survey Report on Ship s Lifting Appliances The report is to be used by the Surveyor to inform the Headquarters of surveys of lifting appliances. Copies of all certificates issued are to be attached to the report Others Any replacement loose gear or rope is to be accompanied with the approved manufacturer s test certificate, and the Certificate of Test and Examination of Loose Gear or the Certificate of Test and Examination of Wire Rope is to be issued after a satisfactory examination or proof test. -11-

15 CHAPTER 2 DERRICK SYSTEMS 2.1 CALCULATING CONDITIONS AND LOADS Application The requirements given in this Chapter are applicable to the slewing derrick rigs, union purchase rigs and derrick cranes. Derrick rigs of special design will be considered on the basis of these requirements Angles to the horizontal of derrick booms For the purpose of determining the forces acting on the derrick systems, the boom angle to the horizontal is to be taken as 15 for light derricks and 25 for heavy derricks. Should the derricks not be operated at the foregoing angles, the boom angle to the horizontal may be increased so as the derrick can be operated in practice, however in no case, the boom angle to the horizontal is to be taken as more than 30 for the light derricks and 45 for the heavy derricks For determining the forces acting on the cargo blocks or built-in-sheaves (if fitted), the boom angle to the horizontal is to be taken as the maximum angle during the operation of the rig in practice and is not to be in general, less than Inclination of ships (1) An angle of heel of 5 and a trim of 2 are assumed as the basic condition of ship during the operation of derrick systems. (2) For light slewing derricks and union purchase rigs, the effect caused by the inclination of ship as prescribed in (1) above can be ignored. (3) For heavy derricks and derrick cranes, the effect caused by the inclination of ship as prescribed in (1) above is to be taken into account. Where the ship would have greater angle of heel or trim than 5 or 2 respectively, the actual angles are to be taken into consideration Basic load of derrick systems The basic load for the calculation of force for the slewing derricks and derrick cranes is to be defined as the safe working load and the self-weights of derrick boom and the relevant tackle above the hook The basic load for the calculation of force for the union purchase rigs is to be taken as the safe working load Friction allowance The allowance due to sheave friction and the stiffness of wire rope is to be taken as: 5 per cent, for blocks with plain or bushed bearing; 2 per cent, for blocks with ball or roller bearing. The requirement is to apply to all lifting appliances Safety factor of ropes The safety factor n relative to the breaking load of wire ropes or fibre ropes is not to be less than the value as given in Table Wire ropes Type and use of ropes Running rigging: cargo runners span tackles slewing guys Standing rigging: mast stays preventer guys Safety Factor n Table Safety factor n n = 0.9 SWL but need not be greater than 5 nor less than 3 The same as for running rigging but need not be greater than Fibre ropes 8 Note: SWL is the safe working load of the derrick rigs, in kn. -12-

16 2.2 SLEWING DERRICK AND UNION PURCHASE RIGS The conditions and loads for the calculation or analysis of forces acting on the derrick system are to comply with the requirements of In the case of heavy derricks, where the cargo runner is arranged in parallel with the span tackle between the boom head and mast head, the tension of span tackle is to be taken as the total force of span tackle minus the tension of cargo runner under the condition that the lifting load is assumed in the lowering operation The working load of slewing guy is to be determined in accordance with Table Slewing guys are not to be substituted by preventer guys. SWL of derrick rigs, in kn SWL < SWL < SWL 588 SWL 735 Working Load of Slewing Guys Table Working load of slewing guys, in kn 0.5 SWL SWL SWL 0.2 SWL Note: Linear interpolation is to be made for the working load of slewing guys where the SWL of derrick rigs is between 588 kn and 735 kn When the derrick rigs are arranged for union purchase operation, the inboard and outboard booms are to be placed at the lowest angle to the horizontal for practical operation and the working range of the rig and the length of derrick booms are to comply with the requirements as shown in Figure m 1.5m S B C L l A A h θ H = h Figure θ boom angles to the horizontal, both angles are equal; L length of hatch, in m; B breadth of hatch, in m; C outreach, in m; S the distance between two boom heads, in m, in horizontal plan; b the vertical height from derrick heel pin; l see ; h see

17 The outreach C beyond the midship breadth is not to be less than 3.5 m or that as required by the owner The inboard boom head in the projection plan within cargo hatch is to be located: (1) with a distance l not more than L/5 from the opposite side of the hatch for which only one pair of derricks are fitted (see Figure 2.2.4); (2) with a distance l not more the L/3 from the opposite side of the hatch for which two pairs of derricks are fitted; (3) with a distance of 1.5 m from the side of hatch Where the angle formed by the cargo runners is assumed to be equal to 120, the minimum headroom h from the joint (triangle plate) of two cargo runners over the top edge of hatch coaming or bulwark is not to be less than: 5 m, for SWL 19.6 kn 6 m, for SWL > 19.6 kn where SWL is the safe working load of the union purchase rig, in kn. Where the headroom h as stated above cannot meet the requirements for practical operation, it is to be suitably increased The force calculation for the union purchase rig is to be such that the thrust of derrick boom and the load of preventer guys will be obtained from the position of the rig which gives the maximum value within its practical working range. In general, the position of the rig as shown in Figure 2.2.5(a) may be used for such calculation, and in such case, the angle between the cargo runners is to be taken as 120 and the position of the triangle plate connecting two cargo runners is supposed at the lowest position as shown in Figure 2.2.5(b). l L 1 4 L R 1.5m 1.5m 30 B C SWL Fig (Symbols L l B C are the same as stated in Figure 2.2.4) (a) Position of union purchase rig (b) Cargo runner and triangle eyeplate The arrangement of union purchase rigs is to be such that the jack-knifing will not occur within any working range of the rig. For this purpose, the resultant of the horizontal components of cargo runner and preventer guys in the direction of boom axis, which is named span relief f h multiplied by tgθ (θ boom angle to the horizontal), is not to be greater than the sum of vertical components of cargo runner and preventer guys f r, see Figure

18 f r Vertical component of preventer gu Vertical component of cargo runner f h θ Compression in derrick boom Cargo runner tension parallel to boom Half weight of boom Figure The working load of the schooner guys in union purchase rig is to be taken as 20 per cent of the safe working load of the rig, but not less than 9.8 kn. 2.3 DERRICK BOOMS Construction of booms (1) The boom may be constructed as a member with uniform diameter and thickness over its full length or as a tapered component which has a mid-length with uniform diameter and thickness connected to the tapered ends; (2) The mid-length with uniform diameter of a tapered boom is to at least be maintained one third of the boom length and the end diameter of the tapered ends shall not be less than 70 percent of the mid-length diameter; (3) The wall thickness of boom is not to be less than 1/50 of the external diameter of the boom at its midlength and need not be greater than 1/30, but in no case be less than 4 mm; (4) The slenderness ratio λ (boom length/effective boom slewing radius) of the boom is in general not to be greater than 150; (5) The boom head is to be adequately strengthened or increase its thickness in way of the portion where the eyeplates for span tackle, cargo block or preventer guy are fitted The materials of derrick booms and their associated fittings are to comply with the requirements as prescribed in Table or with a national standard recognized by CCS, which is appropriate to the intended purpose. Grade of Steel for Derrick Boom and Associated Fittings Table Thickness, in mm t < t < t 40 t > 40 Grade of steel A32, A36 A32, A36 D32, D36 E32, E The safety factor n for the stability of boom with respect to the critical compression as given by the Eler s formula is not to be less than that as required in Table (a). The permissible axial boom thrust compression p is given by the following expression: -15-

19 mej p = kn nl 2 where: m a coefficient, to be taken in accordance with Table 2.3.3(b), intermediate values to be obtained by linear interpolation; E modulus of elasticity for steel = , MPa; L boom length, in m, to be measured from the centre of cargo block eyeplate to the hole centre of boom heel; J o moment of inertia of mid-length section of boom, in cm 4 ; n safety factor for the stability of boom, to be taken in accordance with Table 2.3.3(a), intermediate values to be obtained by linear interpolation; Safety Factor n for Stability of Boom Table 2.3.3(a) Safe working load of derrick rig, in kn Safety factor for stability n Note: The safety factor for stability is applicable to the boom with the slenderness ratio λ less than 145. J1 J0 a L J1 Factor m Table 2.3.3(b) a/l J 1 /J 0 Factor m Note: (1) a is the mid-length of boom; (2) J 1 is the moment of inertia of the cross section of boom end The permissible axial boom thrust may also be calculated in accordance with the theory of elastic stability. For such calculations the effects of bending moment due to the self-weight of boom and the end moment at boom head are to be taken into account. The safety factor n for the stability of boom subjected to axial compression of such calculation is not to be less than that as given in Table Intermediate values are to be obtained by linear interpolation. Safety Factor n for Stability of Boom Subject to Axial Compression Table Safe working load of derrick rig, in kn Safety factor n for stability of boom If the yield strength σ s of steel is greater than 70 per cent of its tensile strength σ b, the yield strength σ s is to be modified, i.e. divided by a coefficient β which is to be taken in accordance with Table Intermediate values are to be obtained by linear interpolation. -16-

20 Coefficient β Table Ratio of yield strength to tensile strength σ s /σ b Coefficient β Note: When the ratio exceeds 0.9, it is to be taken as The end moment at boom head for a conventional derrick rig is to be taken as the algebraic sum of moments in the vertical plane of the derrick boom caused by the span tackle and cargo loads applied to their respective boom head fittings. The horizontal end moments at boom head due to the loads of slewing or preventer guys may, in general, be neglected In the case of a derrick crane, the derrick boom has two span tackles in which the span load is not equally distributed each other provided the boom is not placed at the ship s longitudinal centre line. In such case, a torque will occur at the boom head and is to be taken into account for the calculation of stability in accordance with the requirements in of this Chapter. 2.4 MAST AND DERRICK POST Mast and derrick post are to be supported by at least two decks and effectively connected to the main hull structure. Deck house may be considered as a deck support provided it has an adequate strength. The hull structure or such deck house in way of the supports shall be reinforced. Alternative means which give effective supports for the mast or derrick post will be specially considered The mast or derrick post is to be adequately reinforced where concentrated loads take place, such as in way of gooseneck bearing, span eye fittings and the fittings for mast stay. The toes of brackets and the corners of fittings are not to be placed on the unstiffened panels of plating. Reinforcement is to be made by increasing plate thickness Structural continuity is to be maintained for the structure of components and any abrupt change of section is to be avoided. Openings (such as lightening hole, manhole) are, in general, to be avoided where concentrated loads and high shear forces occur The outside diameter D of the mast or derrick post is not to be greater than the value as given by the following expression: t D = t D = 100 t mm, for t 15 mm mm, for t > 15 mm where: t wall thickness of mast or derrick post, in mm. The minimum wall thickness of mast or derrick post is not to be less than 6 mm; where the mast or derrick is also used as a vent, the minimum thickness is not to be less than 7 mm It is recommended that the outside diameter of mast or derrick post in way of the span eye fitting should not be less than 85 per cent of that in way of the level at supporting deck The forces of span tackle, cargo runner and boom thrust applied to the mast or derrick post are to be calculated (also graphically) in accordance with the relevant requirements as specified in 2.2 of this Chapter, and by which the combined stresses in various sections of mast or derrick post are to be taken into account When calculating the strength of mast or derrick post, the least favourable combination of loading is, in general, to be considered as follows: (1) For mast or derrick post with one derrick: 1 one derrick plumbing one hatch with lowest boom angle to the horizontal; 2 one derrick slewed outboard to its maximum working position. (2) For mast or derrick post with two or more derricks: 1 two derrick plumbing one hatch with lowest boom angle to the horizontal; 2 two derricks, the one for forward cargo hold and the other for the aft slewed outboard on one side of the ship to their respective maximum working position. -17-

21 (3) For mast or derrick post fitted with both heavy and light derricks, the combination of loading resulting from the heavy and light derricks need not, in general, be considered. (4) Should it be possible that greater stress will occur at the position of mast or derrick (including stayed mast) other than above, such conditions are to be taken into account The combined stresse σ t at any particular section of a mast or derrick post are to be taken as: 2 2 ( σ + σ ) 3τ σ t = b c + MPa where: σ b bending stress, in MPa; σ c compressive stress, in MPa, and in general, the compressive stress due to the self-weight of mast or derrick post can be ignored; τ shear stress due to torque, in MPa The safety factor with respect to the yield strength σ s of material for the mast and derrick post, including the crosstree and overhung structure, is not to be less than the values as given in Table Safe working load (SWL) of derrick rigs in kn Safety Factor of Steel Material for Mast and Derrick Post Table Stayed mast Safety factor Unstayed mast including crosstree and overhung structure SWL SWL < SWL < 588 By linear interpolation Where the yield strength σ s of steel used is more than 70 per cent of the tensile strength σ b, the yield strength is to be modified in accordance with the requirements in of this Chapter The grade of steel used for the manufacture of mast, derrick post and its accessories is not to be lower than those as given in Table The arrangement of mast stays is not to obstruct the operation of derrick rig. Turnbuckles are to be fitted at the bottom of the stays and connected to the eyeplates attached to deck, bulwark or deckhouse. The stays are to be set up to an initial tension. The modulus of elasticity of wire ropes for the calculation of elongation of stays may be taken as MPa and the sectional area of the rope may be taken as that of its nominal diameter. Greater value of the modulus of elasticity may be taken provided it is obtained from the actual test. -18-

22 CHAPTER 3 CRANES, LIFTS AND RAMPS 3.1 GENERAL PROVISIONS This Chapter applies to the following types of cranes: (1) deck cranes mounted on ships for handling cargo or containers in harbour conditions; (2) floating cranes or grab cranes mounted on barges or pontoons for operating in harbour conditions; (3) engine room cranes and provision cranes etc. mounted on ships (including floating docks) for handling equipment and stores in harbour conditions; (4) cranes mounted on fixed or mobile offshore installations for transferring equipment, stores etc. or handling manned submersibles and diving systems; (5) cranes mounted on ships for non-manned equipment in an offshore environment, e.g. pipe laying cranes Derrick cranes are not included in this Chapter, they are to be designed in accordance with the requirements of Chapter Shipboard cranes may, in general, be designed in accordance with the requirements of standard service category and offshore cranes are to be designed in accordance with the requirements of specified service category Cranes for transferring persons may be designed referring to the requirements of 3.2, 3.3 and 3.5 of this Chapter, and the relevant requirements in Chapter 4 of the Rules are to be complied with in the case of the protection of personnel Any crane or lifts not covered in the description or environmental conditions as stated in of this Chapter will be specially considered. 3.2 SHIPBOARD CRANES General requirements The requirements of 3.2 are, in general, applicable to the cranes, as stated in 3.1.1(1) to (3), which are designed to operate in harbours or sheltered waters where there is no significant movement of the ship due to wave action and the sea state is not worse than that as described for Beaufort scale No The forces and loads acting on the crane structure are to be determined in accordance with the related operating and environmental conditions. The performance of a crane, such as safe working load, live load, working radius, lifting height, together with the speed of all crane movements and braking frequency etc. are to be clearly specified in design Consideration of forces and loads The following forces and loads are to be taken into account according to the utilization and duty of the particular type of crane: (1) dead load as defined in 1.2.1(14); (2) live load as defined in 1.2.1(11); (3) dynamic forces due to various movements of crane; (4) forces due to the inclination of ship; (5) load swing caused by non-vertical lift; (6) wind forces and environmental effects; (7) load on access ways, platforms etc The crane structure and any stowed arrangements are also to be examined with respect to the stowage conditions as follows: (1) forces due to ship s motion and inclination; (2) wind and environmental effects Basic loads -19-

23 The basic loads applied to the crane comprise the dead load and live load Duty factor Cranes are grouped depending on the nature of the duty they perform and the duty factor φ d of each group of cranes is given in Table The duty factor depends on the frequency of operation and the severity of load lifted with respect to the SWL of the crane concerned and assumes the operating lift not exceeding cycles for normal marine use. Consideration is to be given to appropriately increasing the values in the Table where extra heavy duty is envisaged. Duty Factor φ d Table Crane type and use Duty factor φ d Engine room cranes, provision cranes 1.0 Deck cranes, container cranes, gantry cranes, floating cranes 1.05 Grab cranes Consideration is to be given to the live load and dead load to be effected by the duty factor φ d Dynamic forces and hoisting factor φ h The dynamic forces due to hoisting are those imposed on the structure by shock and acceleration effect. To take this effect into account, the live load is to be multiplied by a hoisting factor φ h which is given by the following expression: φ h = 1 + CV where: V hoisting speed, in m/s, but need not be taken as greater than 1.0 m/s; C a coefficient depending on the stiffness of the crane concerned, taken as 0.3 for jib type cranes, and 0.6 for gantry type cranes. But in any case, the value φ h is not to be taken as less than 1.10 for jib cranes and 1.15 for gantry cranes Dynamic forces due to crane movements When a crane travels along a track or rails, the dynamic forces are to be taken into account as follows: (1) When a crane travels along the rails which are level and smooth, the vertical acceleration acting on the crane is normally low and the vertical reaction force does not occur simultaneously with the maximum dynamic force in hoisting loads, they may, in general, be ignored. (2) The horizontal inertia force is the product of live load together with the self-weight of crane and the acceleration or deceleration which will occur due to the starting or braking of a travelling mechanism. The horizontal acceleration including that of braking is to be supplied by the manufacturer. Where the acceleration is not available but the speed and working condition are known, the acceleration or deceleration a is to be obtained from the following expression: 1 for cranes with low travel speed (V = 0.4 to 1.5 m/s) and with low acceleration: a = 0.15 V m/s 2 2 for cranes with moderate to high travelling speed (V = 1.5 to 4.0 m/s) and with normal acceleration: a = 0.25 V m/s 2 3 for cranes with moderate to high travelling speed (V = 1.5 to 4.0 m/s) and high acceleration: a = 0.33 V m/s 2-20-

24 3.2.7 Transverse forces due to travel motions Consideration is to be given to raking loads which occur when two pairs of wheels or bogies move along a set of rails and produce a couple formed by horizontal forces normal to the rail direction. The horizontal raking force F l is calculated from the following expression: F l = λp N where: P vertical load, in N; λ a coefficient taken in accordance with Figure (a), dependent on the ratio of wheel track L and base b as shown in Figure (b). The wheel base is measured in accordance with Figure (c) dependent on the number of pairs of wheels. λ 0.20 P b L b (wheel track/wheel base) P P b/l L P b/l (a) (b) b ( of wheels or less) b (In case of 6 to 8 pairs of wheels) b ( ) (c) Figure (a) Coefficient λ; (b), (c) Wheel track and wheel base Buffers and buffer forces Forces applied to the crane structure as a result of the travelling crane coming into contact with buffers are to be taken into account The buffer is assumed to have a capacity absorbing the kinetic energy of an unloaded crane which travels at 70 per cent of its rated speed. The forces are to be determined with the reduced travel speed of a crane at the buffering effect Where deceleration devices are fitted which will operate automatically and give effective deceleration to the crane at all times before the crane reaches the end of the track, the reduced speed produced by the devices may be used in calculation For cranes where the lifting load is free to swing, the buffer force is to be calculated by equating the energy capacity of the buffer with the kinetic energy of the crane deadweight, excluding the live load. For cranes where the lifting load is restricted from swinging by rigid guides, the deadweight plus the live load is to be used in the calculation of the forces Slewing and luffing inertia forces The inertial forces acting on live load and crane structure due to slewing and luffing are to be considered. -21-

25 The horizontal inertial force acting on the live load while swinging or luffing can be taken as that produced from the pendulum amplitude of the hoisting rope While the slewing and luffing mechanism accelerate or decelerate, the horizontal inertial forces acting on moving parts and live load are to be taken as 1.5 times the product of its weight and acceleration In general, the effect of centrifugal force acting on the crane structure is small and may be ignored Loads due to ship inclination Shipboard cranes are to be designed to operate safely and effectively in harbors or well sheltered sea areas in inclined conditions specified in Table Consideration is to be given to conditions where it is intended to operate a crane on a vessel at angles greater than those as specified above. Where angles less than those as specified are proposed, calculations are to be submitted to show that such lesser angles will not be exceeded in service. Minimum Heel and Trim Angles Table Ship type Heel (º) Trim (º) Conventional ships (with dimension ratio required by rules) 5 2 Barges with length less than 4 times breadth, and catamarans 3 2 Semi-submersibles 3 3 Semi-submersible platforms 2 2 Self-elevating platforms Forces due to ship motion In the stowed condition the crane, its stowage arrangements and the structure in way are to be designed to withstand forces resulting from the following two design combinations: (1) Acceleration normal to deck of ±1.0g, acceleration parallel to deck in fore and aft direction of ±0.5g, static heel of 30, wind speed of 55 m/s acting in fore and aft direction. (2) Acceleration normal to deck of ±1.0g, acceleration parallel to deck in transverse direction of ±0.5g, static heel of 30, wind speed of 55 m/s acting in transverse direction Alternatively, the force may also be calculated using accelerations obtained from consideration of ship s motions, the static load of components together with the force due to wind speed of 55 m/s acting in the most unfavourable condition. For a conventional ship the parameters (amplitude and period) of the various ship s motions are given in Table (a) and the forces resulting from ship s motions may be calculated in accordance with Table (b). The combinations of static and dynamic forces are to be considered as follows: (1) Roll motions: Static roll + dynamic roll + dynamic heave (at roll angle φ) (2) Pitch motions: Static pitch + dynamic pitch + dynamic heave (at roll angle ψ) (3) Combined motions: Static combined force (dynamic roll + dynamic pitch) Determination of forces due to ship s motion by use of recognized software may be accepted in seakeeping analysis and quasi-static analysis according to the most severe sea state likely to be encountered. -22-

26 Parameters of Ship s Motion Table (a) Motion Maximum single amplitude Period, in seconds Roll 0 ϕ = B T r = GM Pitch 300 ψ = 12e L pp T = 0. 5 p L pp Heave L pp 80 Th = 0. 5 L pp where: L pp length of ship between perpendiculars, in m; GM initial metacentric height of loaded ship, in m; B moulded breadth of ship, in m; ψ taken as not greater than 8 ; e the base of natural logarithms. Static load Motion Roll Pitch Forces due to Ship s Motion Normal to deck Component of force, in N Transverse W cosϕ W sinϕ Parallel to deck Table (b) Longitudinal W cosψ W sinψ Combined W cos( 0.8ϕ )cos(0.8ψ ) W sin( 0.8ϕ ) W sin( 0.8ψ ) Roll ϕy ϕz r ± 0.07 W ± 0.07 W 2 2 T T r r Dynamic load Pitch Heave ψx ψz p ± 0.07 W 2 ± 0.07 W T 2 T L ± 0.05 T L ± 0.05 T p pp W 2 h pp W 2 h cosϕ cosψ L ± 0.05 T pp W 2 h sinϕ L ± 0.05 T p pp W 2 h sinψ Note: Static load means the gravity component of force acting on the ship due to both roll and pitch angles, and dynamic load means the inertia force due to ship s motions (roll, pitch, heave), where: y transverse distance parallel to deck from centreline of ship to centreline of crane, in m; x longitudinal distance parallel to deck from centre of pitching motion i.e. longitudinal centre of flotation to centreline of crane, in m; Z r distance normal to deck from centre of rolling, taken to be at the vertical centre of gravity of the ship, to the vertical centre of gravity of the crane, in m; Z p distance normal to deck from centre of pitching motion to centreline of crane, in m; W weight of crane or its component part, in N Wind loading The wind pressure q due to wind speed is to be determined by the following expression: q = 0.613V 2 Pa where: V wind speed (average speed in a period of 2 minutes), in m/s. The wind speed for the operating condition is to be taken as 20 m/s, and for the stowed condition as 55 m/s. Where it is expected that wind speed can exceed those defined above, then these higher wind speeds are to be considered. -23-

27 The wind force F n acting on the suspended load is, in general, to be calculated from the following expression: For SWL not exceeding 490 kn: F n = 37 SWL N For SWL exceeding 490 kn: F n = 815 SWL N where: SWL safe working load, in kn. Where the handled loads are of specific shape and size, the wind force may be calculated for the appropriate dimensions and configuration The wind force F w acting on the crane structure or individual members of the structure is to be calculated from the following expression: F w = CqA N where: C wind force coefficient in the direction of the wind for the part under consideration, see Table and Figure ; q wind pressure, in Pa; A projected area of the part under consideration, in m 2, on a plane perpendicular to the wind direction. The projected area of a combined structure is the sum of areas of its individual members. l l l l b b d b D length of member l Aerodynamic slenderness = = breadth of section across wind front b Section ratio (for box sections) = or breadth of section across wind front b = depth of section parallel to wind flow d Figure Aerodynamic Slenderness and Section Ratio l D Type Individual members Single lattice frames Force Coefficient C Table Aerodynamic slenderness l/b or l/d Description Rolled sections, rectangular sections, hollow sections, flat plates DV < 6 m Circular sections 2 /s DV 6 m 2 /s b/d Box sections: over mm 2 square over mm 2 rectangular Flat-sided sections 1.7 Circular sections DV < 6 m 2 /s DV 6 m 2 /s Machinery houses Rectangular clad structures on ground or solid base (air flow beneath structure prevented) 1.1 Note: D is diameter of circular section, in m; V is wind speed, in m/s. -24-

28 Shielding factors and wind force acting on sheltered frame or member (1) Where a structure consists of a framework or members such that shielding takes place, the wind force on the windward frame or member and on the sheltered parts of those behind it are to be calculated using the appropriate force coefficient C. The force coefficient on the sheltered parts is to be multiplied by a shielding factor η given in Table Values of η vary with the solidity and spacing ratio as defined in Figure Am Solidity ratio = = A A 0 Spacing ratio = b a b l where: A actual area of the frame, in m 2 ; A 0 outer frame area, in m 2 ; i.e. b l of Figure ; m ordinal number of frames or members; a distance between two neighbouring frames or members, in m; b width of frames or members on the windward, in m; l length of frames or members on the windward, in m. l A Ao ΣAm b l b b b b l a a a a b Figure Solidity Ratio and Spacing Ratio (2) Where there are a number of identical frames or members spaced equivdistantly behind each other in such a way that each frame or member shields those behind it, the wind load F w on those frames or members are to be calculated from the following expression: where n (the number of frames or members) 9: n 1 η F w = CqA N 1 η where n (the number of frames or members) > 9: n 1 η 8 F = + ( ) w CqA n 9 η N 1 η where: C, q, A are the same as specified in ; η shielding factor, given in Table , but not to be taken as less than 0.1; n number of frames or members. -25-

29 Spacing ratio a/b Shielding Factor η Table Solidity ratio A/A Wind loads on lattice towers In calculating the face-on wind load on tower structure, the solid area of the windward face is to be multiplied by the following overall force coefficients: (1) For towers composed of flat-sided sections: 1.7q (1 + η) (2) For towers composed of circular sections: where DV < 6.0 m 2 /s: 1.2q (1 + η); and DV 6.0 m 2 /s: 1.4q (1 + η) where: D and V are as designated in the note of Table , factor η is to be taken from Table for a/b = 1 according to the solidity ratio and spacing ratio of the windward face. The maximum wind load on a square tower is to be taken as 1.2 times the face-on load when the wind blows in the direction of corner Platform and access-way loading Platform and access-way are to be designed to withstand a uniformly distributed load over the full area of 5000 N and a concentrated load of 3000 N on any individual member Operating condition and load combinations The crane design is to be considered with respect to the loads resulting from the following four operating conditions Case 1: For the condition of the crane operating without wind, the design loads are to be considered as follows: (1) dead load; (2) (live load and the horizontal component of live load due to heel and trim) hoisting factor φ h ; (3) the rest most unfavourable horizontal load (usually due to slewing acceleration); (4) the horizontal component of dead load due to heel and trim. The combination of the loads as specified above is given by the following expression: (1) + (2) + (3) + (4) duty factor φ d Case 2: For the condition of the crane operating with wind, the combination of loads is to be: (1) + (2) + (3) + (4) duty factor φ d + L w where: L w the most unfavourable wind load Case 3: The crane is considered in the stowed condition, the combination of loads is to be considered as follows: forces resulting from acceleration due to ship s motions and static inclination together with wind forces appropriate to the stowed condition. The effects of anchorages, locks and lashings, if any, are to be taken into consideration Case 4: For the condition of the crane subjected to specific loading, the following loads need to be considered: (1) coming into contact with buffers; (2) failure of the hoisting wire rope or sudden release of load for crane with counterweight; (3) test loading. -26-

30 Stability against overturning Cranes capable of travelling with loading are to be examined with regard to stability against overturning for the following four conditions: (1) crane operating without wind; (2) crane operating with wind; (3) crane in stowed condition subject to storm; (4) crane subjected to specific loading defined in The loads and forces resulting from the four above conditions are to be multiplied by their respective load coefficients given in Table for the overturning moments relative to the edge in consideration. The crane will be stable provided the sum of the overturning moments is not greater than the uprighting moment. Type of cranes Bridge cranes Jib cranes Conditions Dead loads Loading Coefficients in Four Working Conditions Table Live loads Inertial forces (including live loads) Wind loads Remarks For arm cranes, examination of stability is to be made for: (1) longitudinal direction (arm plane, conditions 1 & 2) (2) transverse direction (travelling direction, condition 3) For cranes without arm, examination of stability be made only for: transverse direction (condition 3) Where anchoring devices (reaction wheel, grasp, etc.) are used during the operation of crane, the forces resulting from anchoring devices may be used in the calculation of the uprighting moment Overturning loads resulting from the ship s inclination are to be considered For floating cranes, the overall stability against overturning is to be checked Allowable stress The allowable stress [σ] for crane structure member is given by the following expression: σ s [ σ ] = MPa β n where: σ s yield strength of steel, in MPa; n safety factor given in Table dependent on the conditions as stated in ; β coefficient given in Table Safety Factor n Table Condition Safety factor n The failure stress σ of steel in elastic modes is given in Table Failure Stress σ Table Mode Symbol Failure stress σ, in MPa Tension σ t 1.0 σ s Compression σ c 1.0 σ s Shear τ 0.58 σ s Bearing σ br 1.0 σ s -27-

31 For components subjected to combined stress, the following allowable stress criteria are to be used: ( σ + σ σ σ + τ ) σ = 3 2 cp x y x y 1.1[σ] MPa where: σ cp combined stress, in MPa; σ x applied normal stress in x direction, in MPa, σ x < [σ]; σ y applied normal stress in y direction, in MPa, σ y < [σ]; τ applied shear stress, in MPa, τ < 0.58 [σ]; [σ] the same as above Allowable stress for stability for members subjected to compression and bending The allowable stress for stability for members subjected to compression is to be taken as the critical compression stress divided by the safety factor n as defined in Table In addition to the checking of the local stability of individual member of a crane jib, examination is to be made to the overall stability of crane jibs for the compression loading. The allowable stress [σ st ] for stability for members subjected to compression is given by the following expression: σ cr [ σ st ] = MPa n where: [σ st ] allowable stress for stability, in MPa; σ cr critical compression stress of member in MPa, as determined according to the slenderness ratio and form of section in accordance with Appendix 1 to the Rules; n safety factor, see Table For members subjected to combined bending and compression, the following stress criteria are to be used to examine their stability: 1 σ m σ c 1 + σ σ n s cr where: σ m applied bending stress, in MPa; σ c applied compression stress, in MPa; σ s yield strength of steel, in MPa; σ cr and n the same as defined in For members subjected to bending stress in both x and y directions, σ m in the above stress criteria is to be substituted by the sum of bending stresses in x direction and that in y direction Overall stability of crane jibs The overall stability of crane jibs is to be checked with respect to critical compressive failure of the jib as a whole with regard to both plan and elevation planes The slenderness ratio is to be calculated from the effective length of the jib divided by the effective radius of gyration in the plane concerned. The effective radius of gyration is given in The effective length of the jib is dependent on the constraint conditions at its ends. For wire rope supported jibs the effective length is to be calculated from the following expression: l e = kl mm where: l e effective length of the jib, in mm; L actual length of the jib, in mm; K coefficient obtained from the two following conditions: (1) In elevation, the jib may be considered as being fixed against translation and free to rotate so that the effective length is taken as the actual length of the jib, i.e. k = 1. (2) In plan, the lower end is to be considered as fixed against translation and rotation and the head is to be considered as partially constrained with respect to translation by the hoist and luffing ropes, the coefficient k is obtained from the following expression: -28-

32 ( D + CH ) R k = 2 RH D + CRl H where: C the ratio of the load applied to the jib head by the luffing wire rope to that applied to the non-vertical part of the hoist wire ropes; R, R H, R l, D and H are dimensions, in mm, as shown in Figure D H L R Rl RH Figure Dimensions of Jib For the jibs with the slenderness ratio greater than that as specified in Table or of very high strength steel construction, the calculations are to be submitted for special consideration Slenderness ratio λ The slenderness ratio λ of compression members with constant radius of gyration is given by the following general expression: kl λ = r where: L actual length of member, in mm; r radius of gyration of member, in mm; k coefficient dependent on the restraint conditions of the supported ends, as shown in Table Restraint conditions Coefficient k Table Coefficient k Constrained against rotation and translation at both ends 0.7 Constrained against rotation and translation at one end and translation only at other end 0.85 Constrained against translation only at each end 1 Constrained against rotation and translation at one end and against rotation only at other end 1.5 Constrained against rotation and translation at one end and free to rotate and translate at other end For members which have constant sectional area and uniformly varying second moment of area, the expression for calculating the slenderness ratio is the same as that given in above, but the radius of gyration r is to be substituted by effective radius of gyration r e. The effective radius gyration r e is given by the following expression: I r = e mm e A -29-

33 where: A sectional area of member concerned, in mm 2 ; I e effective moment of inertia = mi 2, in mm 4 ; I 2 maximum moment of inertia of area of member in the plane concerned, in mm 4 ; m coefficient given in Table (a), (b) and (c) as appropriate. Coefficient m Table (a) I 1 /I m l2 l1 Coefficient m Table (b) I 1 /I 2 a/l l1 l2 l2 l1 L 2 a a 2 2 L 2 Coefficient m Table (c) I 1 /I 2 a/l l2 l2 l1 a L -30-

34 For members subjected to compression the slenderness ratio λ is not, in general, to be greater than that as given in Table Slenderness Ratio λ for Compression Members Table Types of components Slenderness ratio λ Primary members subjected to compression Chords of main truss 120 Member as a whole 150 Secondary members subjected to compression (bracings of main truss or chords of auxiliary truss) Stability of plate against local buckling failure The critical buckling stress σcr c or τ cr for plate subjected to compression or shear against local buckling is given by the following expression respectively: σ c cr 2 t = k c E MPa b 2 t τ cr = k τ E MPa b where: E modulus of elasticity of steel, , in MPa; t plate thickness, in mm; b plate width, in mm; k c compression buckling coefficient, see Table ; k τ shear buckling coefficient, see Table Buckling coefficient φ Table a No. Stress condition Uniform or nonuniform compression,0 φ 1 σ2 σ1 φσ1 α b α = b Buckling coefficient kc 7.59 kc = ϕ = ϕ α+ α ( ) 2 Simple bending or bending with tension as a major stress, φ -1 σ2 σ1 φσ1 α b kc kc = 21.6 = α 2 α + σ2 Bending with compression as a major stress, φ σ1 φσ1 α b k c ' '' ( 1+ ϕ ) k ϕk + 10ϕ ( + ϕ ) = 1 c ' kc buckling coefficient,where φ =0 as shown in col. No.1 k Buckling coefficient,where φ =-1 '' c as shown in col. No.2 c Pure shear α b k k = α = α τ + τ

35 The combined critical buckling stress σ cr p for plate subjected to combined compression and shear stress is given by the following expression: σ p cr = 1+ ϕ σ c + c 4 σ cr 2 c σ + 3τ 2 3 ϕ σ c c 4 σ cr where: σ c compression stress, in MPa; τ shear stress, in MPa; φ see the description under the column stress condition in Table ; σ cr c, τ cr same as defined in above Where the values of σ cr c, 3 τ cr or σ cr p obtained from the expressions as specified in or as appropriate, is greater than the elastic limit of steel which is assumed to be 0.75σ s, the critical buckling stress σ cr c, τ cr or σ cr p are to be substituted by σ cr1 c, τ r1 c or σ cr1 p obtained from the following expressions: 2 + τ τ cr 2 MPa σ τ c cr1 cr1 σ s σ s σ = c cr σ s σ s τ = cr MPa MPa σ σ s σ s σ p cr = 1 p cr where: σ cr c, τ cr or σ cr p are defined in and above; σ s yield strength of steel, in MPa. MPa The allowable stress against the buckling failure of plate is to be taken as the critical buckling stress or modified critical buckling stress, obtained from , or , divided by a safety factor n as given in Table These calculations do not cover the critical buckling stress for plates strengthened with stiffeners. The calculation of critical buckling stress for plates strengthened with stiffeners are to be specially considered otherwise Stability against buckling failure for the thin wall cylinder The thin wall cylinders subjected to the axial compression or combined compression and bending are to be calculated for the stability against buckling failure provided the dimensions of cylinders comply with the relationship as given by the following expression: t R 25 σ s E where: t cylinder wall thickness, in mm; R radius of middle plane of cylinder wall, in mm; σ s yield strength of steel, in MPa; E modulus of elasticity of steel, in , in MPa The critical buckling stress σ cr c for the thin wall cylinders subjected to axial or eccentric compression is given by the following expression: c 0.2Et σ cr = MPa R -32-

36 where: E, t and R are the same as in above Where the critical buckling stress obtained from is greater than the elastic limit of steel which is assumed to be 0.75σ s, the critical buckling stress σ cr is to be substituted by σ cr1 c obtained from the following expression: c σ = s σ cr σ s 1 1 c MPa 5.35σ cr where: σ s, σ cr c are defined in and The allowable stress against buckling failure is to be taken as the critical buckling stress or modified critical buckling stress, obtained from or as appropriate, divided by the safety factor n as specified in Table When the length of the thin wall cylinder is greater than 10R, intermediate ring stiffeners are to be fitted and the spacing of the ring stiffeners are not to be greater than 10R. The moment of inertia of area of the ring stiffener is not to be less than the value as given by the following expression: where: R and t are defined in I 3 Rt 2 R t mm Allowable stress for joints and connections Welded joints The allowable stress for welded joints is to be taken in accordance with Table dependent on the physical properties of the weld metal considered as to be not less than the parent metal. The actual stress for the fillet welds is to be calculated on the basis of throat dimension of the welds. Type of welds Allowable Stress for Welded Joints Table Tension and compression Allowable stress, in MPa Shear Full penetration butt weld σ s /n 0.58 σ s /n Fillet weld 0.7 σ s /n 0.58 σ s /n Note: σ s yield strength of parent metal, in MPa; n safety factor as given in Table Bolted joints Black bolts (ordinary grade bolts) are not to be used for primary joints or joints subjected to fluctuating or reversal of load. For joints using precision bolts, defined as machined or cold finished bolts fitted into drilled or reamed holes, the allowable stress with respect to the external applied load is not to exceed that given in Table Where the joints are subjected to fluctuating or reversal of load the bolts are to be pretensioned by controlled means to 70 to 80 per cent of their yield stress. Type of loading Allowable Stress for Bolts Table Allowable stress, in MPa Load cases 1 & 2 Load cases 3 & 4 Tension σ s /2.5 σ s /1.85 Single shear σ s /2.6 σ s /2.0 Double shear σ s /1.75 σ s /1.30 Combined tension and shear 2 2 σ + 3τ σ s /2.1 σ s /1.56 Bearing σ s /1.1 σ s /0.83 Note: σ s yield strength of bolt material, in MPa. Load cases are defined in

37 Slewing ring and slewing ring connecting bolts The slewing ring and the slewing ring connecting bolts are to be calculated for their static and fatigue strength The ring mounting flange is to be of rigid construction. The mating surfaces between the ring and the pedestal flange are to be, in general, steel to steel and the packing material is not recommended between the joint faces. The properties of the ring material are to comply with the requirements of The bolts for connecting the ring and pedestal flanges are to be of ISO 898/1 steel Grade 8.8 (σ b 800 MPa, σ s = 0.8σ b ), 10.9 (σ b 1000 MPa, σ s = 0.9σ b ) or 12.9 (σ b 1200 MPa, σ s = 0.9 σ b ) or equivalent and are to be pretensioned by controlled means to 70 to 90 per cent of their yield strength. The properties of the connecting bolt material are to comply with the requirements of The maximum load P of bolt due to external loading is given by the following expression: where: M design overturning moment, in N mm; Q design axial load, in N; D pitch circle diameter of bolts, in mm; n number of bolts. M Q P = 4 N nd n Materials The crane is to be constructed of steel complying with the applicable requirements of CCS Rules for Materials and Welding or the relevant standards acceptable to CCS The selected steel grade is to provide adequate assurance against brittle fatigue taking account of the material tensile strength and thickness and the environment in which the crane is designed to operate and is, in general, to comply with the Charpy V-notch test requirements given in Tables and Wire rope safety factor, breaking load and sheave-rope ratio The safety factor n of wire ropes for both running and standing application are not to be less than the value given by the following expression, but need not be greater than 5 or less than 3: 10 n = 4 0.9SWL where: SWL safe working load of crane, in kn The minimum breaking load Q b is given by the following expression: Q b = nw N where: n safety factor of wire rope required, obtained from ; W the static load in the wire rope taking due account of the friction in the sheaves over which the wire rope passes, in N The ratio of sheave diameter measured at the bottom or rope groove to wire rope diameter is not to be less than 19: Braking safety factor The braking safety factor for various mechanisms of lifting appliance is the ratio of braking torque to the possible maximum static torque on the shaft of the brake (including the torque due to wind load and inclination load). The braking safety factor for hoisting or luffing mechanism is not to be less than 1.5 if providing one set of such mechanism, and not to be less than 1.25 for each if providing two sets of such mechanism. -34-

38 3.3 OFFSHORE CRANES Application This Section applies to cranes which are designed to operate in offshore environments. Those are defined as sea environments in which there is significant movement of the ship or installation on which the crane is mounted due to wave action. The sea state will, in general, be in excess of that described by Beaufort No.2. The above-mentioned cranes cover jib cranes, A frames and fixed structures used for lifting operations The requirements of 3.2 of this Chapter are to apply to offshore crane design except where specific requirements are defined in this Section Cranes mounted on offshore installation used solely for lifting operations on the installation itself may be considered as shipboard cranes as defined in 3.2 of this Chapter Travelling gantry cranes will be specially considered on the basis of this Section Service category and duty factor Except the case as specified otherwise, the design of offshore cranes is to be made in accordance with specified service category. The duty factor φ d = 1.20 is to be used for all offshore cranes Dynamic forces The dynamic forces due to hoisting for offshore cranes are to include the effect of relative movement of the crane besides load due to normal hoisting shock and dynamic effects The hoisting factor φ h is considered to be dependent on the design operational sea conditions which may be defined by the Beaufort No., sea state No. or wave height and period, and is to be calculated from the following expression: where: φ w wave factor given in Table ; K the crane system stiffness, in MPa; Q l live load, in N. φ h = φ w K Ql For initial design calculations K may be taken as Q l Beaufort No. Minimum Hoisting Speed, Wave Factor and Offlead angle for Various Sea Conditions Table Significant wave height Minimum Sea state No. hoisting speed 1 V H 3 (m) h (m/s) α β α β Wave factor φ w Offlead angle ( ) Case 1 Case ~ ~ Notes: α offlead in plane of jib; β offlead normal to plane of jib. For case 1 and case 2, see When the design operational sea state is known, the hoisting factor φ h may be calculated from the following expression, but in no case less than that specified in 3.2.5: -35-

39 1 where: H 3 1 H 3 φ h = T design significant wave height, in m; T design wave period, in seconds; K and Q l same as defined in To calculate the crane system stiffness the following combination of structural elements of hoist rope system, luffing rope system, crane jib are to be considered. For wire rope the modulus of elasticity is to be taken as MPa When a motion compensator, shock absorber, or similar device is fitted, proposal to use lesser hoisting factors will be specially considered Offlead angles The design offlead angles are to be taken in accordance with the sea conditions as given in Table Proposals to use lesser value will be specially considered should arrangements to reduce offlead angles be fitted Hoisting speed The minimum load hoisting speed is to be high enough to ensure that after the load is lifted re-contact is not to occur with the ship due to wave action. The minimum load hoisting speeds to avoid re-contact for the various sea conditions are given in Table When the design wave height and period are specified, the load hoisting speed may be obtained from the following expression: K Q l 1 H V h = T m/s 1 where: H 3 and T are the same as defined in Slewing rings The properties of the slewing ring material are to comply with the requirements of The ring is to be considered with respect to static loads resulting from the worst load combination as specified in and associated with an allowable stress based on a safety factor not less than 2.5 with respect to the yield strength of steel. The ring is also to be considered with respect to fatigue loading with an allowable stress based on a safety factor not less than 1.5. The fatigue loading is to be taken from the load combination Case 2 as specified in multiplied by a load spectrum factor 0.7. The fatigue failure stress is to be taken from the S-N curve obtained from a type testing on the basis of cycles. Slewing rings are to meet the requirements for both static and fatigue strength The slewing ring bolts are to be made of steel having an impact properties not less than those as given in The steel grade is, in general, not to exceed ISO 891/1 Grade The bolts are to be designed to be able to withstand both the static and fatigue loading as specified in taking due account of pretension Magnetic particle examination is to be made to the machine-finished components of the ring Materials The crane is to be constructed of steel complying with the applicable requirements of CCS Rules for Materials and Welding or the relevant standards acceptable to CCS The selected steel grade is to provide adequate properties against brittle fracture. Charpy V-notch test requirements are to comply with Tables and , in J, according to the thickness and tensile strength of steel used For the design operating temperature below -10 the Charpy V-notch test requirements will be specially considered. -36-

40 3.3.8 Safety factor and breaking loads of wire ropes The rope safety factor n o for offshore cranes is to be determined from the following expression but in no case be less than that obtained from : n o = φ h n where: n safety factor obtained from ; φ h hoisting factor obtained from The required breaking load of the rope is given in accordance with , but in this case, n is to be substituted by n o as specified in SUBMERSIBLE HANDLING SYSTEMS General requirements This Section applies to installations which are designed to handle manned submersibles in offshore conditions. Offshore conditions are defined as those which exist in an open sea environment in which the sea state does not exceed that described by Beaufort No.5. Special consideration will be given to cases where service in a more severe sea is envisaged The requirements of 3.2 of this Chapter are to apply to submersible handling systems except where specific requirements are defined in this Section The submersibles as defined in this Section are to include diving bells Duty factor A single duty factor φ d used for all submersible handling systems is to be taken as Basic loads The live load Q 1 to be used for submersible handling systems is to be taken as the greater of: (1) the maximum in air weight of the submersible and exposed length of hoisting rope; (2) the maximum weight of the exposed length of hoisting rope, together with the combined in water weight of the submersible and submerged length of rope Where the handling system does not lift the submersible through the air/water interface, the live load may be taken as that defined in (2) Hoisting factor A hoisting factor φ h to be used for submersible handling systems incorporates the effects of the submersible passing through the water/air interface and is to be taken as Offlead angles Submersible handling equipment operates in an offshore environment where there is significant movement of the ship and/or submersible due to wave action. To allow for these conditions an offlead angle of 10 assumed to be acting in both planes simultaneously is to be used for design purposes Stowage arrangements The stowage arrangements are to be designed to withstand the most severe combination of motions which can occur when the handling system is stowed. In the case of ship mounted installations reference is to be made to It additionally may be necessary to consider the effects of green sea loading, in which case a value of 8400 N/m2 is to be used as an equivalent hydrostatic pressure Materials The materials for making submersible handling systems are to comply with the applicable requirements of

41 3.4.8 Rope safety factors The rope safety factors for manned submersibles are to be as follows: (1) taken as 8.0 for steel wire ropes; (2) taken as 10.0 for man-made fibre ropes The rope safety factors for unmanned submersibles are to be as follows: (1) obtained form 3.3.8, but to be taken as not less than 6.0 for steel wire ropes; (2) obtained from (1) multiplied by 1.25 for man-made fibre ropes If in addition to the primary hoist rope a secondary system of recovery is employed using another hoist rope, the minimum safety factor for this is not to be less than HEAVY LIFT CRANES General requirements This Section applies to cranes mounted on barges, semi-submersibles or other vessels, used in construction and salvage operations within harbors or sheltered waters or in equivalent offshore environmental conditions. The safe working load of the main hook is to be not less than 1600 kn Specifications of operational and environmental conditions are to be provided for design of heavy lift cranes Unless specifically provided otherwise, the requirements of 3.2 of this Chapter apply also to the heavy lift cranes defined in Where the safe working load of the auxiliary hook is less than 1600 kn, the structural components are to be designed in accordance with Hoisting factor The hoisting factor φ h to be used for heavy lift cranes is to be taken as Offlead angles The limits of offlead angles of hoisting wire ropes (in plane of jib and normal to plane of jib) are to be provided. Offlead angles may include the ship s heel and trim angles. 3.6 CRANE PEDESTALS General requirements The strength of crane pedestals is to be considered in accordance with the loading conditions as specified in 3.2, 3.3 and 3.4 and their allowable stress is to be obtained in accordance with the requirements of Pedestals, in general, are to be carried through the deck and effectively connected with the main hull structure. Alternative support arrangements will be specially considered. The pedestal flange in way of the slewing ring bearing is to be of rigid and levelled construction. Where the flange is stiffened with brackets, the spacing of the brackets is not to be greater than that of two connecting bolts Allowable stress The allowable stress [σ] for pedestals is to be given by the following expression: σ s [ σ ] = MPa β n where: σ s yield stress of steel, in MPa; n safety factor, to be taken as the value given in Table under the loading conditions specified in ; β coefficient given in Table according to the ratio of yield strength to tensile strength. -38-

42 Safety Factor n Table Loading condition Safety factor n The failure stress in the failure modes under elastic condition is defined in Table Materials The grade of steel for crane pedestals is to comply with the requirements of Table Where the pedestal is connected to the hull support by bolts, the requirements for the bolts are to be equivalent to those for slewing ring bolts. 3.7 CARGO AND VEHICLE LIFTS General requirements This Section applies to cargo and vehicle lifts which are operated whilst the ship is in a harbour or sheltered waters, and where the cargo or vehicles may be stowed on the ship in their stowed position whilst the ship is at sea. These lifts may be designed in compliance with the requirements of Standard Service Category, otherwise they are to be designed in compliance with those of Specific Service Category The operating and stowed loading conditions are to be clearly specified in all submissions together with hoisting speeds and braking frequency For the operating condition the lift is to be considered with respect to the following loads and forces: (1) load due to self-weight of lift; (2) applied loading; (3) dynamic forces due to hoisting/lowering; (4) static forces due to inclination of the ship The lift structure and locking mechanism are also to be examined with respect to the stowed condition for the following criteria appropriate to the ship s characteristics: (1) load due to self-weight of lift; (2) applied load due to vehicle or cargo loading; (3) forces due to ship s motion and static inclination; (4) weather loading, where appropriate Basic loads The self-weight load, L m, is the load imposed on the hoisting mechanism by the weight of the structure and machinery The applied load, L c, is the loading imposed on the lift structure by the cargo or vehicle The safe working load (SWL) is the maximum load for which the lift is certified and is equal to the maximum value of L c Dynamic forces and coefficient To take account of the acceleration and shock loading the self-weight L m and applied load L c are to be multiplied by a coefficient of Forces due to ship s motion For the operational condition, the lift is to be designed to operate safely and efficiently at an angle of heel of the ship of 5 and an angle of trim of 2 acting simultaneously. If it is intended to operate a lift at angles greater than above, the lift is to be designed for the proposed angles and the certificate marked accordingly. -39-

43 In addition to the operating conditions, the lift and its locking mechanism are all to be designed to withstand the conditions when stowed: (1) acceleration normal to deck of ±1.0 g; acceleration parallel to deck in fore and aft direction of ±0.5 g; static heel of 30 ; (2) acceleration normal to deck of ±1.0 g; acceleration parallel to deck in transverse direction of ±0.5 g; static inclination of Alternatively, for a conventional ship of which the characteristics are known, the forces may be calculated for the combination of static and dynamic forces in accordance with the requirements as specified in Design loads The design loads are to be consistent with the ship s loading manual and include the details of the number and spacing of vehicles the lift is designed to accommodate, the type of vehicles, their weight, axle loading, tyre print dimension, and number and spacing of wheels and supports. Figures (a) to (d) give the typical loading information, in which the maximum axle loading of 20 ft container trailers is 175 kn and that of 40 ft container trailers 159 kn. Due account of asymmetric loading is to be taken where applicable. -40-

44 490kN 171.5kN kN kN kN kN (196kN+98kN) kN 196kN 196kN kN kN 196kN 196kN 196kN 196kN 196kN kN kN 304kN kN kN kN 637kN kN kN( ) kN 164kN Figure (a) Typical Loading Data -41-

45 70kN 30kN 30kN kn kN kN 50kN 50kN kN kn 130kN 70kN 70kN kn kN 600 Figure (b) Typical Loading Data -42-

46 120kN 120kN 60kN 60kN kN kN kn kN kN 140kN 120kN 120kN 30kN kN kN kN 2000 kn kN Figure (c) Typical Loading Data -43-

47 200kN 200kN 200kN 200kN kn kN 250kN 250kN 250kN kn kN 300kN 300kN 300kN kn kn/m kn kn Figure (d) Typical Loading Data -44-

48 In addition to the vehicle loading the lift is to be considered with respect to uniform deck loading appropriate to the deck or decks at which it is stowed Where the lift forms part of ship s watertight structure, it is to comply with the watertight requirements, as appropriate Load combination of various loading conditions Case 1 operating condition The load combination is represented by the following expression: 1.2 (L m + L c ) + L h1 + L h2 where: L m self weight load; L c applied load; L h1 level load due to 5 heel; L h2 level load due to 2 trim Case 2 stowed condition The lift is to be considered with respect to the forces resulting from the acceleration due to ship s motion, together with the forces due to static heel and inclination as defined in Case 3 test load condition The load combination of the self weight and the test load is represented by the following expression: where: L t test load obtained from Table Safe working load SWL (L m + L t ) Test load L t Table Test load L t 1.25 SWL 196 ~ 490 SWL + 49 > SWL Allowable stress The allowable stress [σ] in the elastic failure modes is given by the following expression: [σ] = σ/(nβ) MPa where: σ failure stress, in MPa, to be taken in accordance with ; n safety factor, to be taken in accordance with Table ; β coefficient given in Table according to the ratio of yield strength to tensile strength. Safety Factor n Table Load case case 1 case 2 case 3 Safety factor n For component subjected to combined stresses the following allowable stress criteria are to be met: σ σ 2 + σ 2 σ σ + 3τ 2 1.1[σ] cp = x y x y where: σ cp combined stress, in MPa; σ x applied normal stress in x direction, in MPa, and to be less than [σ]; σ y applied normal stress in y direction, in MPa, and to be less than [σ]; τ applied shear stress, in MPa, and to be less than 0.58 [σ]; [σ] to be the same as

49 3.7.8 Allowable stress against plate buckling failure For plate subjected to compression or shear or combined compression and shear, the critical buckling stress is to be obtained in accordance with , and respectively The allowable stress against the buckling failure is to be taken as the critical buckling stress given in , divided by the safety factor as specified in Table The above calculations are not applicable to the critical buckling stress for the plates strengthened by stiffeners. The calculation of buckling stress for plates strengthened by stiffeners will be specially considered Deck plating thickness The deck plating thickness t is not to be less than that as given by the following expression: t 1.47 AL mm = w where: A stress factor obtained from Figure for the tyre print and plate dimensions as defined in the Figure; L w load, in kn, on the tyre print, for close-spaced wheels the shaded area shown in Figure may be taken as the combined wheel print. μ lc v s A PR=3.0 PR=2.0 PR=1.0 PR=2.0 PR=0.5 PR=1.0 PR=0.5 Type print ratio (PR) = (μ/ν) Plate panel ratio = (le/s) Plate panel ratio 2.5 Plate panel ratio = 1.0 Note: For intermediate values of tyre print ratio and plate panel ratio the stress factor A is obtained by interpolation PR=3.0 v s Figure Deck Plating Stress Factor A -46-

50 Deflection criteria The deflection of the lift structure or individual members with respect to the cranes operating in the loading conditions of Case 1 and Case 2 as specified in are to be limited to l/400, where l is the distance between two supports, in mm Where applicable, the maximum deflection is to be limited to ensure the watertight integrity of the ship is maintained Guide rails Guide rails or other arrangements are to be provided to restrict horizontal movement of the lift during operation Where guide rails are fitted, the maximum deflection resulting from the horizontal component of load is not to be greater than 6 mm The working clearance between the lift and guide rails is to be such as to allow free vertical movement of the lift Stowage locks The stowage locks are to be provided for the lifts placed in stowed condition and to resist the vertical, forward/aft and lateral loads as defined in Case 2 of Arrangements are to be such that the locks do not work loose or impair the watertight integrity of the ship Hoisting arrangements Where chains are used as a part of the hoisting arrangement, the safety factor of chains is not to be less than Where wire ropes are used as a part of the hoisting arrangement, the safety factor n of wire ropes is given by the following expression: n = L mc but not less than 4.0 nor greater than 5.0 where: L mc weight of lift in which the rated load is carried, in kn Materials The selected steel grade for the construction of lifts is to have adequate performance against brittle fracture taking account of the material tensile strength, the thickness and the environment in which the lift is proposed to operate and, in general, the Charpy V-notch test requirements for such steel grade are not to be less than those given in Tables and VEHICLE RAMPS General requirements This Section applies to the moveable vehicle ramps installed on ships where the loading or unloading operation is carried out in a harbour or sheltered waters, these ramps may be designed in compliance with the requirements of Standard Service Category. Where the ramps are designed to operate in conditions other than those as defined above, they are to be designed in compliance with the requirements of Specific Service Category The loaded and stowed conditions are to be clearly specified in all submissions, together with the hoisting speeds, braking frequency and operating angles for the intermediate positions of the ramp For the loaded condition the ramp is to be considered for the worst possible combination of angles and support arrangement (supported by the quay and/or its hoisting mechanism) with respect of the following loads and forces: (1) load of self-weight; (2) applied load; -47-

51 (3) dynamic forces due to vehicle movement For raising and slewing manoeuvres the ramps are to be considered with respect to the following loads and forces: (1) load of self-weight; (2) applied load, where appropriate; (3) dynamic forces due to hoisting/slewing; (4) forces due to ship s static inclination For the stowed condition the ramp and its locking mechanism are to be considered with respect to the following loads and forces: (1) load of self-weight; (2) applied load, where appropriate; (3) forces due to the ship's motion and static inclination; (4) weather loading, as appropriate Basic loads The self-weight load, L m, is to be taken as the weight of the ramp and multiplied by a coefficient of 1.2 to take account of dynamic forces due to manoeuvring the ramp The applied load, L c, is the static load on the ramp due to cargo or vehicles and is to be multiplied by a coefficient of 1.1 to take account of the vehicle movement When the ramp is manoeuvred and loaded both L m and L c, L m and L c are to be multiplied by a coefficient of Forces due to ship's motion Ramps are to be designed to operate in a harbour or sheltered waters where there is no significant motion of ship due to wave action For both lowered and manoeuvred conditions the ramp is to be designed to operate safely and efficiently at an angle of heel of 5, and an angle of trim of 2 acting simultaneously The slope of the ramp is to comply with the requirements of Table , and where the ramp is designed for ship to shore use, this angle is to include the effects of heel and trim defined above. Slope of Ramp Table Slope Type of vehicle Car Trailer Heavy trailer Container trailer Maximum slope 1 : 5 1 : 6 1 : 9 1 : 9 Generally selected slope 1 : 6 1 : 7 1 : 10 1 : The ramp and its locking mechanism are to be designed to withstand the following conditions when the ramp is in its stowed position: (1) acceleration normal to deck of ±1.0 g, acceleration parallel to deck in fore and aft direction of ±0.5 g, static heel of 30 ; (2) acceleration normal to deck of ±1.0 g, acceleration parallel to deck in transverse direction of ±0.5 g, static heel of Alternatively, where the ramp is fitted to a conventional ship and the ship s characteristics are known, the forces may be calculated for the combination of static and dynamic forces of for the ship s motions and accelerations obtained from Tables (a) and (b) Design loads The design loads of ramps are to be consistent with the ship s loading manual and are to include the details of the number and spacing of vehicles the ramp is designed to carry, the type of vehicles, their weight, axle loading, tyre print dimensions, and number and spacing of wheels and supports. Figure gives typical ramp loading information. -48-

52 In addition to the vehicle loading, where a ramp in its stowed position forms a part of a deck it is to be considered with respect to the uniform deck loading. Similarly where the ramp forms part of the ship s watertight structure, it is to comply with these requirements as appropriate Load combinations Case 1 lowered condition The load combination is represented by the following expression: L m + 1.1L c + L h1 + L h2 + L h3 where: L m self-weight load; L c applied static load; L h1 load due to 5 heel; L h2 load due to 2 trim; L h3 load due to ramp angle Case 2 stowed condition The ramp and locking mechanism are to be considered with respect to the forces acting on the self-weight and applied load as appropriate resulting from accelerating due to ship s motions and static inclination together with weather forces appropriate to the stowed position Case 3 manoeuvring condition The combined loads and forces applied on the ramp are represented by the following expression: (1) For ramps which are unloaded during manoeuvring: (2) For ramps which are loaded during manoeuvring: 1.2 L m + L h1 + L h2 1.2 (L m + L c ) + L h1 + L h2 where: L m, L c, L h1 and L h2 the same as defined in above Allowable stresses and deflection criteria The allowable stresses for ramp structure are as defined in and inclusive The deflection of ramp between supports with respect to Case 1and Case 2 is to be limited to l/400, where l is the distance between supports, in mm. Where applicable, the deflection in the stowed condition (Case 2) is to be limited to ensure the watertight integrity of the ship is maintained Hoisting and slewing arrangements Where chains are used as part of the hoisting or slewing arrangements they are to have a minimum safety factor of Where wire ropes are used as part of the hoisting or slewing arrangements they are to have a safety factor n given by the following expression: 10 4 n = 0.9L but not less than 4.0 nor greater than 5.0 where: L weight of the ramp (for ramps which are unloaded during manoeuvring) or weight of the ramp together with the applied load acting on the ramp (for ramps which are loaded during manoeuvring), in kn Materials The selected grade of steel for the construction of ramps are to comply with the requirements given in Table The ramp materials are also to have adequate performance against brittle fracture taking account of the material tensile strength, thickness and the environment in which the ramp is proposed to operate and, in general, the Charpy V-notch test requirements for such steel grade are not to be less than those given in Tables and

53 3.9 PASSENGER AND CREW LIFTS General requirements This Section applies to the lifts in conformity with the following conditions: (1) driven with electric or hydraulic power; (2) permanently installed in ships and employing an enclosed car; (3) suspended by wire ropes; (4) running at rigid guides between decks; (5) the transfer of persons or persons and goods; (6) the rated speed not exceeding 1.0 m/s. Lifts designed for a higher rated speed than 1.0 m/s will be specially considered The lift is to comply with the relevant requirements of the Administration, if appropriate, in addition to the requirements contained in this Chapter The rated load, minimum stopping distance, buffer stroke, type of hoisting drive, type of safety gear and buffer are to be clearly specified in all lift submissions The lift is to be designed such that it can be stowed, either manually or automatically, in the event of the specified operational conditions being exceeded For the operating conditions the lift is to be considered with respect to the following forces: (1) self-weight of car; (2) rated load; (3) dynamic forces due to lift motion; (4) forces due to ship s motion and static inclination For the stowed condition the lift is to be considered with respect to the following forces: (1) self-weight of car; (2) forces due to ship s motion and static inclination Basic loads The self-weight, L m, is the load imposed on the hoisting mechanism by the weight of the permanent components of the lift car structure and machinery The rated load, L c, is the load imposed on the lift car by the persons and is not to be less than that obtained from Table Rated Load for Car (N) Table Rated load (N) Maximum available car area, in m 2 Maximum number of persons Notes: 1 For intermediate loads the area is determined by linear interpolation. 2 The maximum number of persons carried is given by: L c /735, rounded down to the nearest whole number where L c is the rated load. 3 If the rated load exceeds by more than 15 per cent that indicated in the Table for maximum available car area, the maximum number of persons permitted is to correspond to that area. -50-

54 3.9.3 Dynamic forces resulting from operation of safety device or car striking buffers The dynamic forces F due to the operation of the safety devices or the car striking the buffers are to be taken into account and obtained by the following expression: F = φ s (L m + L c ) N where: φ s = V 2 /s; V rated speed, in m/s; s minimum stopping distance or buffer stroke, whichever is the lesser, in m; L m, L c see and above The rated speed, minimum stopping distance and buffer stroke are to be obtained from the lift specification to which the lift is constructed. Table gives the typical values of governor tripping speed and stopping distances and Figure gives the typical buffer strokes. Rated Speed and Stopping Distance for Car Table Rated speed, in m/s Governor tripping speed, in m/s Stopping distance, in m minimum maximum 0 ~ (v, m/s) Figure Stroke for Various Types of Buffer Forces due to ship s motion Passenger lifts and their associated machinery and structure are to be designed to operate at sea with respect to the following conditions: (1) roll: ±10, with 10-second period; (2) pitch: ±7.5, with 7-second period. -51-

55 In addition to the operational conditions the lift and associated machinery and structure are to be designed to withstand the forces resulting from consideration of the following conditions where it is in stowed condition: (1) roll: ±22.5, with 10-second period; (2) pitch: ±7.5, with 7-second period; (3) heave: amplitude = L, with 10-second period,where L is the Rule length of the ship Load combination The lift and its associated machinery and structure are to be considered with respect to the design loads resulting from the following conditions: (1) Case 1: the loads are to be obtained from the following expression: (L m + L c ) φ s + L h1 + L h2 where: L m self weight load; L c rated load; φ s the dynamic factor due to safety devices operating or car striking buffer in ; L h1 horizontal force due to roll; L h2 horizontal force due to pitch. (2) Case 2: the self-weight of the lift is to be considered with respect to the forces resulting from the acceleration due to the ship s motion as defined in Allowable stress The safety factor and allowable stress are to be in accordance with and Deflection criteria The deflection of the car structural members is not to exceed l/600 mm, where l is the distance between supports, in mm The deflection of the guide rails is not to exceed l/400mm, or 3 mm, whichever is the lesser, where l is the distance between supports, in mm The car walls or doors in their closed position are to be able to resist without permanent deformation or elastic deformation greater than 15 mm a force of 300 N evenly distributed over a circular or square area of 500 mm 2 applied parallel to the deck from inside towards the outside of the car. The doors are to be capable of operating normally after being subjected to this load The car roof is to withstand without permanent deformation a force of 2000 N applied at any position and normal to the deck Guides At least two steel guides are to be installed and the surface finish is to be sufficiently smooth to allow the free running of the car or counterweight The guides are to be designed to resist forces resulting from the application of the safety devices, which are obtained from the following expression: where: φ s1 coefficient given in Table ; L m, L c the same as described in (1) (L m + L c ) φ s1 Coefficient φ s1 Table Type of safety devices Coefficient φ s1 Instantaneous safety device 2.5 Captive roller type safety device 1.4 Progressive safety device

56 The allowable stress for the guides is to be calculated in accordance with the method as specified in and the slenderness ratio concerned is to be calculated in accordance with Safety gear The car and counterweight are to be provided with safety gear capable of operating only in a downward direction by gripping the guides. It should be capable of stopping the fully laden car or counterweight, at the tripping speed of the overspeed governor, even if the suspension device breaks. The safety gear is to be tripped by an overspeed governor, but the counterweight may be tripped by failure of the suspension gear or by a safety rope The safety gear may be of the instantaneous type with buffered effect or of instantaneous type where the rated speed is not in excess of 0.63 m/s The counterweight safety gear may be of the instantaneous type The jaws of safety devices are not to be used as guide shoes Overspeed governors Tripping of the overspeed governors is to occur at a speed of at least 115 per cent of the rated speed but not more than: (1) 0.8 m/s for instantaneous safety gears except for the captive roller type; (2) 1.0 m/s for safety gears of the captive roller type; (3) 1.5m/s for instantaneous safety gear with buffered effect The tripping speed of an overspeed governor for a counterweight safety gear is to be higher than that for the car safety gear but is not to exceed it by more than 10 per cent The force exerted by the overspeed governor when tripped is not to be less than the greater of: (1) 300 N; or (2) twice the force necessary to engage the safety gear The breaking load of the overspeed governor operating rope is to have a safety factor of 8.0 with respect to the force required to operate the safety gear. The rope is not to be less than 6.0 mm in diameter and the ratio of the bottom of the sheave groove diameter to rope diameter is not to be less than 30: Buffers The car and counterweight are to be provided with buffers at their bottom limit of travel. If the buffers travel with a cage or countweight they are to strike against a pedestal at least 0.5 m high at the end of the travel Where energy accumulation type buffers are used the total possible stroke of the buffers is to at least be equal to twice the gravity stopping distance corresponding to 115 per cent of the rated speed, i.e.: s = 0.135V 2 m but not less than m. where: s stroke, in m; V rated speed, in m/s. Buffers are to be designed for the above stroke, under a static load of 4 times the self-weight of the car plus its rated load or 4 times the weight of the counterweight as appropriate With the rated load in the car the average deceleration due to the buffers acting on a free falling car is not to exceed 1.0 g and the maximum deceleration not to exceed 2.5 g Hoisting arrangements The hoisting arrangements may consist of: (1) traction drive using sheaves and ropes; or (2) positive drive, if the rated speed is not greater than 0.63 m/s, consisting of: 1 drum and rope without counterweight; or 2 sprocket and chain The ratio of sheave groove diameter or drum to rope diameter is not to be less than 40 : 1. Where drum drive is used, the drum is to be grooved and the fleet angle of the rope in relation to the groove is not to be greater than 4 either side of the groove axis. -53-

57 Not more than one layer of rope is to be wound on the drum and when the car rests on its fully compressed buffers one and a half turns of rope are to remain in the grooves The safety factor of suspension ropes, defined as the ratio of minimum breaking load of the rope to the maximum load on the rope when the car is at its lowest level and subjected to its rated load, is not to be less than those given in Table Drive mode Safety Factor for Rope Table Safety factor Friction drive with three ropes or more 12 Traction drive with two ropes 16 Drum drive A device is to be fitted at one end of the hoisting arrangements to equalize the tension in the ropes or chains Where compensating ropes are used, the ratio between the bottom of sheave groove diameter and diameter of the rope is not to be less than 30: Lift trunk and motor room All lift trunks and machinery spaces are to be completely enclosed, suitably ventilated, and constructed to give fire protection in compliance with the requirements of the SOLAS Convention in force Clearances around the car are also to be guarded or arranged to preclude the possibility of personnel falling between the car and trunk Only pipes and cables belonging to the lift may be installed in the trunk and the travelling cables are to be protected by an internally smooth metal trough which is to be provided with a slot having rounded edges to allow free passage of the cables leaving the lift car and be of sufficient width to allow passage of free hanging loop of the travelling cable Where two or more lifts are fitted into one trunk, each car and its associated counterweight is to be separated by means of sheet steel over the full height of the trunk The lift trunk is not to be part of the ship s ventilation ducting but is to be ventilated by an independent system The trunk entrances are to be located to prevent the ingress of water or cargo into the trunk, and the deck area at entrances are to be nonslip and of approved material which will not readily ignite Where the lift is for crew, the headroom of the trunk (the space above the car roof when the car is in its highest position) is to incorporate an escape hatch of 500 mm 500 mm minimum dimensions Lift car and counterweight The car is to be constructed of steel or equivalent non-flammable material, have a non-slip floor and be provided with at least one handrail where access for persons is clearly available. A load plate is to be prominently displayed specifying the safe working load both in persons and kilogrammes The car entrances are to be provided with doors of an imperforate type fitted with devices to prevent untimely opening and slamming. The clearance between the car and car door is not to be more than 6 mm The car and counterweight are to be guided over their full travel, including overtravel and an independent guidance medium to limit car movement in the event of casting failure is to be provided where cast iron shoes or guide shoes contained in cast iron housings are used Counterweights are to be constructed of steel or equivalent material and filler weights are to be securely clamped in position within steel frames. Concrete filler weights are not permitted. A suitable device is to be fitted to stop and support the counterweight in the event of rope failure Traction drive lifts are to incorporate a device to stop and support the car for the following conditions: (1) when a start is initiated, the lift machine does not rotate; (2) the car or counterweight is stopped in downward movement by an obstruction which causes the ropes to slip on the driving pulley The device as specified in is to function in a time not greater than the lesser of the following values: -54-

58 (1) 45 s; (2) time for the car to travel the full travel, plus 10 s, if the full travel time is less than 10 s, the time is to be taken as 20 s The device as stated above is not to affect either the inspection or electrical recall operation Emergency means of escape For crew lifts the trunk is to be fitted with a ladder over its entire length leading to the escape hatch in the headroom For lifts intended solely for passengers a suitable ladder is to be provided to give access to the lift car roof from a landing door and either the same or another provided to give access into the car from the emergency opening in the car roof. These ladders are to be kept in a watch-keeping room or room accessible to competent persons A trap door in the car roof of the lift with suitable access to it from the inside is to be provided. Where the lift is solely for passengers the trap door is to be fitted with a mechanical lock which can only be operated from the outside. Where the lift is solely for crew the trap door is to be fitted with mechanical lock which can be operated from the inside and outside the car For crew lifts an access hatch is to be provided in the headroom of the trunk. Opening the hatch from the outside is only to be possible by means of a special key which is to be kept in a box immediately by the hatch Notices in Chinese and English languages or pictographs as necessary, describing the escape routine are to be fixed in the following locations: (1) inside the car; (2) on the car roof; (3) inside the trunk, adjacent to each exit STRENGTH OF SUPPORTING STRUCTURE OF CRANE PEDESTALS General requirements This Section applies to the design and strength analysis of the supporting structure in way of connection of the crane pedestal to hull structure. Where there is no requirement specified in this Section, the relevant requirements in PART TWO of CCS Rules for Classification of Sea-Going Steel Ships are to be complied with The supporting structure is the portion of hull structure, on or in which the pedestal, eyeplates, pin seat, anchorage, tripping elements of a lifting appliance are fitted and which directly bears the forces acting on such components. The supporting structure is to be capable of withstanding the most unfavorable design load and is to have sufficient strength to ensure normal operation and equipment safety of the crane In addition to the requirements of this Section, the supporting structure is to fully comply with the requirements for the same portion of hull structure Plans and documents The following plans and documents are to be submitted for approval: (1) Structural arrangement plan, local structural strengthening plan, detailed plans of connections between pedestal and deck and between supporting structures (details of such connections), covering all components in the area of the supporting structure The following plans and documents are to be submitted for information: (1) Arrangement of jib (boom) and derrick post; (2) Details of loads acting on pedestal; (3) Strength calculations, including a. description of operation conditions and load combinations; b. wind, wave and current parameters of the most severe operating sea state and stowage condition; c. report of seakeeping analysis and motion response calculation or model test report, as appropriate; d. description of calculation model, including element types, boundary conditions; e. calculation results, including deflection/deformation and yield, buckling. -55-

59 In addition to and , electronic data of the calculation model may be required Materials and welding of components The requirements for materials and welding of the supporting structure are based on the primary structure defined in Chapter 6, and the survey requirements for welding of direct connections to the crane pedestal (derrick post) are based on the special structure in Table Structural details Connection details are to be so designed that stress will be reasonably transferred between connected components. Expansion, increased thickness (without doubling plate) and smooth tapering of the connection, high tensile steel, etc. may be used to reduce stress level and/or decrease so far as possible the effects of stress concentration So far as practical, holes are to be avoided in way of the components directly connected to crane pedestal and derrick post and the ends of such components. Where this is unavoidable, compensation for the purpose of safety is to be made The derrick post is to extend continuously through the upper (main) deck into the hull and terminate at a vertical supporting structure which is adequate in strength. Brackets, floors, girders, etc. are to be fitted in way of connection between the post and deck so as to effectively transfer horizontal loading from all directions to the supporting structure. The design is to avoid excessive stress acting on the deck plate connected to pedestal and derrick post. Where necessary, Z-direction steel may be locally arranged within 1 m of the intersection of connections in accordance with Transfer of great tensile stress in through-thickness direction is to be avoided so far as practical to prevent possible lamellar tearing of the plate. Where this is unavoidable, Z-direction steel complying with CCS Rules for Materials and Welding is to be used In addition, structural details are to be designed and constructed in compliance with the applicable requirements of PART TWO of CCS Rules for Classification of Sea-Going Steel Ships Design loads Design loads are generally to be based on the operating conditions and load combinations specified in 3.2 to 3.5, covering at least the following maximum loading: (1) vertical loading; (2) horizontal loading; (3) overturning moment; (4) torque The inertial forces of the crane in response to and due to the ship s motions are to be obtained according to and in addition, may be determined by recognized software in seakeeping analysis and quasi-static analysis according to the most severe sea state likely to be encountered For wind loads, horizontal inertial forces and other horizontal loads as well as overturning moments, the most unfavorable bearing angles of their actions in respect to the supporting structure are to be obtained by searching trial calculation methods or alternatively, typical bearing angles of such actions in longitudinal, transverse and different oblique directions may also be selected according to experience and practical operating conditions Models for calculation When checking the strength of supporting structures, three-dimensional finite element model is to be applied, so far as possible, in the analysis to more exactly describe the distribution of structural response in all directions. Where beam grillage or plate girders are used, the model is to be reasonably simplified and be more conservative. The analysis is to be based on the theory of linear elasticity. In general, consideration will not be given to deducting corrosion margins from scantlings in the model The principles for extent, element types and boundary conditions of a three-dimensional model are as follows: -56-

60 (1) Extent: The structural model is generally a local three-dimensional one (hereinafter referred to as local model), centred on the centroid of a plane rectangle (a b) for effects of the foundation and extending outwards for a distance respectively at least one time the length and width corresponding to the rectangle (3a 3b). This extension reaches vertically from the foundation plane to the first platform (deck) under main deck or at least D/4 (D being moulded depth). Where there is no primary supporting member of the structure at the boundary taken in the above way, the model is to further extend until the boundary is at such supporting member, see Figure (1). For the pedestal of a heavy lift crane taking a large portion of the ship s width, the calculation model for its supporting structure is to be appropriately extended, depending on the size of the pedestal, to take a complete longitudinal 3-dimensional block covering shell plating, see Figure (2). In order to take account of the interaction of the derrick post and supporting structure, consideration is to be given to incorporating into the model a portion of the derrick post extending above deck, see Figure The principles for element selection, properties and meshing etc. of the model are as given in CCS Guidelines for Direct Strength Analysis of Oil Tanker. For better observation of the effects of openings in high stress areas, it is recommended that meshing of the local area along the edge of an opening be appropriately refined. The meshes are generally to be refined to a size between one third and one fourth of the original size; (2) Boundary conditions: The boundary conditions are to be so assumed that calculation results of the elements under consideration in the centre area will not be affected. In general, free or fixed support may be taken into account, or Table may be followed: Boundary Conditions for Local Model Table Boundary condition Linear translation Angular rotation Location U x U y U z θ x θ y θ z Fore and aft end faces A, A1 Constrained Free Free Free Constrained Constrained Left and right end faces B Constrained Constrained Constrained Free Free Free Bottom face C Free Constrained Free Constrained Free Free where: x, y, z representing axial directions along ship s length, width and moulded depth respectively; end face symbols see Figure (1). Figure (1) -57-

61 Figure (2) In general, the load for calculation is to be applied to the top of derrick post (if any) or pedestal model, and the resultant force is to act at the geometric centroid of the end face in question. It is recommended that the load be applied by MPC (multipoint constraint/master and slave nodes), see Figure Figure For large slewing cranes, the load applied on the supporting structure (e.g. wheel pressure of the pedestal) is to be reasonably distributed, if applicable Strength criteria For all loading conditions, the stresses taken in calculation for components are not to exceed the permissible values. In this case, the permissible stress is taken as the material yield strength divided by the corresponding safety factor in Table