SNAME Greek Section Presentation

Transcription

1 Risks of IACS Classed Container Carriers Change Class Notation to "General Cargo" that can carry High Density Break Bulk Cargo Including Iron Ore/Steel Products & Class Certification SNAME Greek Section Presentation By Eur. Ing. Peter D. Contraros C.Eng MRINA [Permanent Member of RINA s Delegation at IMO] PDC Maritime S.A. Naval Architects & Marine Corrosion Consultants c/o AP&A Ltd 32, The Mall, London W5 3TJ mail@pdcmaritime.com Tel: Mob: +44 (0) (UK) Mob: (Greece) Web Site: The study commissioned by the American P& I Club 1

2 Design Issues for Conversion of Container Ship into General Cargo Ship Regulatory Requirements Stability [Intact & Damage] Damage experience Longitudinal strength [Buckling] Structural behaviour when carrying high density cargoes (i.e. steel products or iron ore) Unloading iron ore by grabs and mechanical shovels (bulldozers) Application of IACS UR S26 S27 - Modified Ship Dangerous Goods limitations for the Modified Ship Conclusions 2

3 Geometry Container Carriers v Bulk Carriers 3

4 Three Dedicated Container Carriers carrying Class Certificates as General Cargo used as a basis of the study L = 190 m 2100 TEUs DWT 34,000 B = 28.0 m Year of Built 1987, 1987 & 1989 D = 15.5 m/11.0m Changed to General Cargo Suitable to Carry Iron Ore 4

5 Class Notations Ship Types & related cargo densities Bulk Carriers (as defined in SOLAS Ch. XII CSR for Bulk Carriers) BC-A (Max. Cargo density 3.0 t/m3) - max. tank top loading Iron Ore Alternate Holds and/or Iron Ore in Homog. Mode + GRAB(20) BC-B (Max. Cargo Density 3.0 t/m3) - max. tank top loading Iron Ore in Homogeneous Mode + GRAB(20) BC-C (Max. Cargo Density < 1.0 t/m3) Number & size of steel coils on wooden dunnages for BC-A & BC-B Flooding of each cargo applies Damage & Intact Stability applies Rate of ballast/de-ballasting over 600 tons/hour (about Handy size BC DWT=35,000) Container Carriers Maximum carrying Capacity of TEUs General Cargo Vessels Perhaps max. tank top loading Number & size of steel coils on wooden dunnages Damage & Intact Stability applies (new ships & SOLAS major conversions) Rate of ballast/de-ballasting about 400 tons/hour (for GC of DWT=35,000) 5

6 SOLAS Ch. XII & IX Definition of Ships Carrying Heavy Bulk Cargoes Bulk Carrier as defined in IACS Z is also included by IMO as an additional ship shape for compliance with SOLAS Ch. XII 6

7 Definition of Homogeneous Loading Conditions Definitions Homogeneous Loading Condition Highest filing If the ratio of Lowest filing No Homogeneous Loading Condition 1.2 Then the Loading is NOT Homogeneous [as per IACS UR S18.1] Highest filing Lowest filing 7

8 Container Carrier Changed Class Notation to General Cargo (Cert. issued by an IACS Class) Removal of Cell Guides Approval of Intact Stability (IMO Res A.749(18)) & Loading Manual for carrying cargoes Homog. with max. S.G t/m3 or in another occasion approval for above for a single intern. voyage with iron ore cargoes with density of 1.5 t/m3 (DRI included). No damage (probabilistic) stability analysis requested by Class to be carried out Checking / renewals of some hatch cover s rubber packing but not testing required for wather-tightness as a General Cargo Class Certificates issued stating that the vessel is General Cargo Carrier + Registry on behalf of Flag Admin. or Statement of fact that the vessel may carry ore from Venezuela to China Without notifying the Flag Administration as a major conversion 8

9 Container Carrier converted to General Cargo Questions to be asked & Applicable Rules - Risk Is it considered Major Conversion as per SOLAS Ch-1 Reg. 1(b)? [a major maritime flag Admin. confirmed that is a Major Conversion] Intact & Damage stability required to be carried out for the anticipated loading including iron ore [Risk if not carried out] Is Hatch Cover tested for weathertightness as per ICLL [Risk of fire explosion damage of cargo flooding] What is the rate of loading and unloading as a function of ballasting & de-ballasting capability of the vessel? [Operational Risk] Is the vessel s structure (local and buckling due to long. strength increased GM) suitable to carry Iron Ore & steel products? [Structural Risk] Is the vessel capable to unload by GRAB & mechanical shovels (i.e. bulldozers)? [Structural Risk] 9

10 DH36 Comparison of two similar in geometry and size vessels with different scantlings AH AH EH36 Dedicated Container Carrier [re-classed as General Cargo] Bulk Carrier BC-A [Iron Ore in Altern./Homog. Loading] Risk - Structural Damages of converted Container Carrier 14.0 Spacing EH EH36 Spacing L = 190 m B 28.0 m D = 15.5 m / 11.0 m 2100 TEUs DWT 34,000 Max. Tank Top Load: 13.5 t/m 2 Iron Ore (Hom) S.G t/m 3 L = m B 29.0 m D = 15.0 m / 10.5 m DWT 34,000 Max. Tank Top Load: 22.0 t/m 2 Iron Ore (Hom) S.G. 3.0 t/m AH DH36 Spacing 810 Sp. 825 No GRAB Notation Not specified Steel Coils Year of Built 1987 & 1989 Mandatory GRAB(20) Notation Steel Coils: 2 tiers of 1.6 m x15t/coil on 3 dunnages Year of Built Spac Spac ,

11 Bulk Carrier Loading in an Iron Ore Terminal Currently is reaching 12,000 tons per hour Vessel s rate of ballasting & de-ballasting - RISK 11

12 Damage Experience of Vessel during loading while is de-ballasting RISK Not required by Class See anything wrong??? 12

13 Damage Experienced by M/V MSC NAPOLI caused by BUCKLING due to Hull Girder Strength - RISK? Class s Justification As Quoted from MAIB Report: The classification rules applicable at the time of the vessel s construction did not require buckling strength calculations to be undertaken beyond the Vessel s amidships area PROBLEM EXAMINED WHILE SHIP AFLOAT NOT IN THE SEA BED 13

14 Increase of Dynamic Loading caused by High Density Cargoes Increase of GM will result to: Reduce the period thus increase accel. Loads at Inner skin increased Risk of damage of Inner Skin structure Unsustainable acceleration at bridge (Human Risk) 14

15 Inner Bottom Plating of Container Carriers is not designed to carry Steel Products / Coils Point Loads on I. Btm Plating & Stiffeners 15

16 4900 Relaxation of weather-tightness applicable to Container Carriers and not to General Cargo Carrier & yet the ships certified to carry iron ore products - RISK??? 2 heights of Superstructure 2 x 2300 = 4600 mm. FBD Dk. 16

17 Hatch Cover & Coamings Risks against Weather-tightness Container Carrier Hatch Coaming without compression bar Risk Weather-tightness not assured Bulk Carrier Hatch Coaming with compression bar Minimal Risk Cargo Damage & Explosion Compression bar Hatch Cover Closed Compression bar 17

18 Typical of hatch covers of Container Carrier converted into General Cargo that may carry iron ore (including DRI) as Certified by IACS Class Torn rubber packing at hatch cover panel Expanding foam had been placed at side of hatch panel prior to tightness testing 18

19 Uncertainties as per IACS Recom. 46 for Bulk Carriers Risks for Cargo Ships? DB Girders transfer the load to T. BHDs and then to Side Shell IACS States: It is recommended that high density cargo be stowed uniformly over the cargo space Asymmetric loading during Ballast Exchange Coating in DB constantly suffered from mechanical damages starting from 19 the 1 st day of grab use

20 IACS UR S1A Requirements BLOCK LOADING (every two adjacent Holds Loading versus Draught) Container vessel converted to General Cargo suitable to carry iron ore cargoes Homog. Theoretical Explanation

21 Theoretical Explanation

22 Required Plate Thickness due to GRAB loading for a list of containers built around 80s - around 200 m in length RISK? 22

23 A list of Bulk Carriers built between 80s - 90s and about 200 m in length - Limited Risk 23

24 Typical Unloading by 20 ton Grabs and Bulldozers RISK? Not required by Class for a General Cargo Carrier Major Operational Risk 24

25 Typical Cargo Hold of a KAMSARMAX B/C Unloading grain - Amsterdam s Cargill Grain Terminal >8 ton 25

26 DRI (fines) fire following contamination with sea water No weather-tight hatch covers will increase RISK 26

27 27

28 Carriage of DRI as per INTERCARGO DRI (A) Briquettes, hot moulded - Monitoring requirements DRI (B) Lumps, pellets, cold-moulded briquettes - Moisture < 0.3% - Hold must be inerted - Monitoring requirements DRI (C) By products - Moisture < 0.3% - Hold must be inerted - Monitoring requirements 28

29 Positions of the Vents IACS UR S26 & S27 Fore Deck layout of the inspected ship Fore Deck of MV Derbyshire 29

30 Typical obstructions Risk to damage from Grabs Container Carrier w/o the Cell Guides with potential Risk to damages during unloading Bulk Carrier with smooth surfaces with minimal Risk to damages during unloading Shelves + Container Fittings At T. BHD 30

31 Typical obstructions Risk to damage from Grabs Aftermost CH of a Container Carrier Aftermost CH of a Bulk Carrier Shelves + Container Fittings At T. BHD Smooth Surfaces Inner BTM 31

32 Typical obstructions Risk to damage from Grabs No. 1 Cargo Hold of a Container Carrier with typical shelves for container stack No. 1 Cargo Hold of a Bulk Carrier with clear surfaces for loading bulk cargoes 32

33 CONCLUSIONS Conversion of a dedicated Container into General Cargo Carrier is a change of vessel type & as such, should be considered to be major conversion & satisfy the following: Damage stability (probabilistic approach) Calculate Hull Girder Strength including Buckling as per IACS UR S11 Prohibit to carry any form of DRI Ore Prohibit to carry any Iron Ore unless the Hull is strengthened for use of GRAB(20) Ballasting and De-ballasting should be controlled by prepared Loading Conditions 33

34 CONCLUSIONS (cont ) Class should address the Conversion as a Major Conversion (SOLAS) subject to the Flag Administration written agreement Heavy Density Bulk Cargoes like Steel Products / Coils should be approved by Class accounting for Dynamic Loading Trimming of Cargo is to be calculated and specified in the O.M. Hatch Covers are to be modified in order to maintain weather-tightness at all times Small hatches and Vents fwd to comply with IACS UR S26 & S27 Structure assessment for use of GRAB & mechanical shovels Minimise obstructions to avoid risks to stevedores damage 34

35 The Thinker by Rodin Originally designed to be Dante pondering the massive Gate of Hell END

36 FORTHCOMING PRESENTATION ON IMO BMP4 [BEST MANAGEMENT PRACTICE AGAINST PIRACY] RECOMMENDED BEST MANAGEMENT PRACTICES ON THE USE OF NON-LETHAL MEASURES TO DETER BOARDING BY PIRATES

37 IMO CIRC\MSC\01\1337 SUGGESTED PLANNING AND OPERATIONAL PRACTICES FOR OWNERS, OPERATORS, MANAGERS AND MASTERS OF SHIPS TRANSITING THE GULF OF ADEN AND OFF THE COAST OF SOMALIA RECOMMENDED BEST MANAGEMENT PRACTICES ON THE USE OF NON-LETHAL MEASURES TO DETER BOARDING BY PIRATES

38 Razor Wire Coating Gunwales electrified barriers but are not recommended for hydrocarbon

39 Watercraft immobilizing apparatus & system Use of steel arms Use of Paravan instead of steel arms