TABLE OF CONTENTS INTRODUCTION SCOPE NORMATIVE REFERENCES DEFINITIONS AND ABBREVIATIONS... 3

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1 TITLE SPECIFICATION FOR STEEL DISTRIBUTION POLES REFERENCE REV CP_TSSPEC_033 1 DATE: NOVEMBER 2014 PAGE: 1 OF 16 TABLE OF CONTENTS Page INTRODUCTION SCOPE NORMATIVE REFERENCES DEFINITIONS AND ABBREVIATIONS REQUIREMENTS General Design Construction Specific requirements Inspection and testing Packing and marking Drawings and documentation... 6 Annex A Mast requirements table... 7 Annex B - Revision information... 8 Annex C - Technical schedules A and B... 9 Annex D Stock Items... 15

2 DISTRIBUTION POLES CP_TSSPEC_033 1 PAGE 2 OF 16 FOREWORD Recommendations for corrections, additions or deletions should be addressed to the: Technology Services General Manager City Power Johannesburg (Soc) Ltd P O Kiosk Booysens 2016 INTRODUCTION Steel poles are used in City Power s area of supply in street lighting and distribution applications. The quality of the poles is very important as their failure could result in serious consequences and can also results in loss of lives. 1 SCOPE This specification covers City Power s requirements for steel poles for distribution in accordance with SANS NORMATIVE REFERENCES The following documents contain provisions that, through reference in the text, constitute requirements of this specification. At the time of publication, the editions indicated were valid. All standards and specifications are subject to revision, and parties to agreements based on this specification are encouraged to investigate the possibility of applying the most recent editions of the documents listed below. SANS 044:1983, Welding the fusion welding of steel. SANS 182-1:1973, Conductors for overhead transmission lines. SANS 0225:1991,The design and construction of lighting masts. SANS 657-1:1989, Steel tubes for scaffolding and for structural and general engineering purposes. SANS :1986, Aerial bundled conductor systems. SANS ISO 1461:2000, Hot-dip (galvanised) zinc coatings. SANS / NRS 041 Overhead power lines for conditions prevailing in South Africa Part 2: General design considerations

3 DISTRIBUTION POLES CP_TSSPEC_033 1 PAGE 3 OF 16 3 DEFINITIONS AND ABBREVIATIONS The definitions and abbreviations in SANS 0225 shall apply to this specification. 4 REQUIREMENTS 4.1 General All poles shall comply fully with the requirements of SANS 0225 and this specification The poles shall be suitable for use at a mean altitude of m above sea level in an environment subject to heavy industrial pollution at ambient temperatures of -15 C to 65 C The poles will be installed in locations subject to high wind loading (as detailed in clause 4.2 below) and high lightning ground flash density (> 10 flashes/km 2 /year) The poles shall be designed and approved and certified by an individual who is professionally registered with the Engineering Council as a structural engineer in accordance with SANS 0225 and manufactured from new materials. 4.2 Design The steel tubes used shall comply fully with SANS The poles shall be manufactured of grade 300W steel, with a minimum yield stress of 300 MPa and a minimum tensile strength of 450 MPa, in accordance with SANS The poles shall be designed in accordance with SANS 0225 to support luminaires, the maximum number, mass and projected area of which are given in Annex A, as well as the loading detailed on Drawing CP_TSDRAW_004 Sheet 9 and in clause 4.4 of this specification In addition, the poles shall be designed to support advertising signboards and the additional cantilever loading that will be imposed on these masts. The boards measure approximately 1225 mm (H) 900 mm (B) and are mounted approximately 3,0 m from ground level (measured to the lower edge of the board) in most areas. In exceptional circumstances, mainly in CBD areas, they may be mounted at a height of up to 4,0 m in order to avoid being damaged by road users The steel poles, when loaded as detailed above, shall be capable of withstanding a fluctuating wind load in accordance with the requirements of SANS The terrain category shall be Category 3, and the wind velocity shall be 40ms -1. Other information required (including force coefficients C f ) is given in Annex A Under the conditions detailed in SANS 0225 and those given above, the horizontal and vertical deflections shall not exceed the requirements of SANS The design for all earth mount poles shall include sub-surface fins, the purpose of which is to prevent the pole from rotating about its own axis as a result of wind loading exceeding the soil bearing pressure. The size of the fins shall be determined by the structural engineer, taking into account terrain category, wind velocity, outreach, pole and attachment areas, projected luminaire areas, force coefficients and other relevant data Poles may be of any hollow cross section and vertical profile meeting the requirements of this specification and SANS 0225, but City Power may, at its sole discretion, reject any tender which it considers unsuitable for any reason.

4 DISTRIBUTION POLES CP_TSSPEC_033 1 PAGE 4 OF Poles must have a minimum outside diameter (at the ground line) as detailed in Annex A. Designs using smaller diameters will not be considered under any circumstances The design of each pole shall be accompanied by comprehensive strength calculations certified by a qualified professional structural engineer. As this structural engineer will take full responsibility for the design of the masts, he or she is free to deviate from the drawings for structural reasons. For instance, the structural engineer may feel that the strength of a particular pole is inadequate, and he or she is therefore at liberty to increase the pole thickness or diameter, etc. These changes must be detailed in the strength calculations as well as in the Deviation Schedules, found in the A and B Schedules. 4.3 Construction All poles shall be supplied as a unitary construction (i.e. in one piece) All changes in diameter shall be by means of swaging or continuous tapering. Under no circumstances will welded pieces (pipe reducers) inserted into the poles be accepted All joints shall be bevelled prior to welding and shall present a symmetrical appearance after welding. In addition, all joints (other than those designed for later assembly) shall be designed and manufactured to ensure that there is no ingress of water into the interior of the pole All poles require a sacrificial steel corrosion protection sleeve. These sleeves shall be at least 3 mm thick and conform to Drawing CP_TSDRAW_004 Sheet 8. The sleeve shall be welded to the pole prior to galvanising with a continuous seal weld at the top and bottom of the sleeve. The second weld shall be carried out immediately after, or simultaneously with, the first weld All poles shall have an M10 nut welded to the pole at a height of 1,5 m from the top of the poles. This is to provide a point for earthing the pole when it is carrying overheard conductors or ABC. The corresponding full-thread M10 bolt shall be supplied fitted into the nut. The arrangement shall be such that the full length of the bolt is able to enter the nut All earth mount poles shall have a 60 6 mm anti-sink flat bar (with a minimum thickness of 3,5 mm) roughly shaped to the inside base diameter, welded symmetrically across the base opening, with the flat surface at 90 to the pole axis All earth mount poles shall have fins in accordance with clause welded to the pole below ground level (at 90 to the cable entries) to avoid the pole rotating about its own axis as a result of the wind loading exceeding the bearing pressure of the soil. As a rough guide, the size of the fins should not be less than mm All welding shall be continuous and in compliance with SANS 044, Parts 1 to 4. All welds shall be dressed where necessary After manufacturing is complete, but before galvanising may commence, poles shall have all weld slag removed by shot- or sand-blasting and a visual inspection shall be carried out to ensure the efficiency of this operation. In addition, the poles shall be internally and externally degreased and all grit, loose rust, welding flux and spatter, rough edges and burrs shall be removed All poles shall be hot-dip galvanised in accordance with SANS ISO The minimum thickness of the zinc layer shall be 90 µm. The process used shall comply completely with the requirements of SANS ISO No material may be removed from the pole either mechanically or chemically after galvanising has been carried out.

5 DISTRIBUTION POLES CP_TSSPEC_033 1 PAGE 5 OF All items shall be protected against corrosion by either hot-dip galvanising as detailed above or by being manufactured of stainless steel. All possibility of galvanic action shall be avoided All threaded articles shall use standard metric threads. External threads may not be undercut. 4.4 Specific requirements Dis series masts The Dis series masts shall be manufactured in such a way that the top is completely closed and permanently sealed In addition to the requirements of SANS 0225 and this document, the Dis series masts shall be designed to carry the items and loadings shown in Drawing CP_TSDRAW_004 Sheet In addition to the above, the poles are expected to carry low voltage aerial bundled conductor (ABC) in accordance with SANS 1418 or low voltage hard drawn bare copper (HDBC) conductor in accordance with SANS Tenderers are required to consult these documents for accurate information concerning the characteristics of the conductors, as the information given below is for information only The ABC will be in following configuration: mm 2 phase conductors, 1 70 mm 2 neutral supporting conductor and 1 25 mm 2 auxiliary conductor. The approximate mass per metre of the bundle is 1,51 kg and the design load (UTS /2,5) is approximately 8,0 kn The HDBC conductor will be in the following configuration: mm 2 phase conductors, mm 2 neutral conductor and 1 16 mm 2 auxiliary conductor. The approximate mass per metre per conductor is 1,04 kg and the design load (UTS /2,5) is approximately 20,0 kn In addition to to above, the Dis series masts shall be designed and manufactured to carry an additional radial tip loading of 6,0 kn in any direction Stay pedestals The stay pedestals shall be manufactured in such a way that the top is completely closed and permanently sealed In addition to the requirements of SANS 0225 and this document, the stay pedestals shall be designed to stay poles carrying the items and loadings shown in Drawing CP_TSDRAW_004 Sheet The stay pedestals shall have a diameter of not less than 190 mm and a length of 4,3 m. The thickness shall be in accordance with the loading but 6,0 mm is preferred The stay pedestals shall have a suitable facility near the top to attach one end of a stay wire, the other end being attached to a pole. 4.5 Inspection and testing In addition to the requirements listed below, all poles shall comply with the test requirements of SANS City Power reserves the right to inspect the manufacture s place of production All tests shall done in accordance with SANS 0198, SANS 0225 and SANS ISO 1461.

6 DISTRIBUTION POLES CP_TSSPEC_033 1 PAGE 6 OF The authority may also require the welding on 10% of the poles to be radio-graphed and evaluated. The maximum width of any isolated slag inclusion shall not exceed 3 mm, and the total length of isolated slag inclusions in any continuous length of weld shall not exceed 4% of the length of that weld. In addition, no more than four isolated slag inclusions of a maximum width of 3 mm in this length shall be permitted In addition to the above, no cracks shall be permitted, and penetration, lack of fusion, undercutting and porosity shall receive attention In the event of poles failing to perform on site (City Power) the entire consignment of poles shall be replaced at the tenderer s expense. 4.6 Packing and marking A metal name plate, at least mm in size and using letters at least 10 mm high, shall be permanently fixed 2,0 m from the top of each pole. The name plate shall preferably use raised coloured lettering, although other permanent and robust lettering will be considered, provided full details are supplied The name plate and method of fixing shall have a service life at least equal to that of the pole, and shall remain in place and legible even if the pole suffers serious structural damage of any sort The name plate shall include the following information: manufacturer s name, month and year of manufacture, and the user reference number as detailed in Annex A All poles shall be weld marked with the user reference 1,0 m above the ground line. The weld mark, which shall be carried out before galvanising preparation, shall consist of a neat raised weld run on the exterior of the pole, with letters approximately 100 mm high Masts shall be bundled with stainless steel strapping for delivery City Power shall off-load, at its own cost, any poles delivered to any City Power store. Any items delivered else where shall be off-loaded at the contractor s own cost, and City Power shall not assist in any way whatsoever. 4.7 Drawings and documentation The attached drawings, Sheets 8 and 9 of Drawing CP_TSDRAW_004 are integral to this specification. If there are discrepancies between this written specification and the drawings, the written specification shall take precedence The design of each pole shall be accompanied by comprehensive strength calculations certified by a qualified professional structural engineer. In addition, detailed drawings and documentation as required as per SANS 0225.

7 PAGE 7 OF 16 Annex A Mast requirements table Description User Reference Overall Height Mounting Height Mounting Type Minimum Outside Diameter Maximum mass per luminaire Maximum projected area of luminaire Maximum number of luminaires per pole C f Drawing Plain Mast Dis1 9,2 m 8 m 1,2 m earth 140 mm 25 kg 0,225 m 2 1 1, Plain Mast Dis3 10,7 m 9,5 m 1,2 m earth 165 mm 25 kg 0,225 m 2 1 1, Stay Pedestal - 4,3 m - Direct burial 190 mm

8 PAGE 8 OF 16 Annex B - Revision information DATE REV. NO. NOTES First Issue November Second issue Provision of an earthing stud

9 PAGE 9 OF 16 Annex C - Technical schedules A and B For Plain Mast Dis1 Schedule A: Purchaser's specific requirements Schedule B: Guarantees and technical particulars of equipment offered Item Sub-clause of CP_TSSPEC_ 033 Description Schedule A Schedule B 1 Name of manufacturer XXXX 2 Place of manufacture XXXX 3 Manufacturer s identification reference Dis Standard to which mast complies SANS Does the design of the mast comply with all the requirements of SABS 0225 and this specification? Is the mast design approved and certified by a qualified professional structural engineer? Standard to which steel tubes comply SANS Material of mast Grade 300W steel Is the mast design accompanied by comprehensive strength calculations? Standard to which welding complies SANS Standard to which galvanising complies SANS ISO Mass of mast kg XXXX Is the mast marked in accordance with the requirements of 4.6? Is all the information requested in supplied? 15 Calculated natural frequency of mast Hz XXXX 16 Expected service life of mast years 30 (min) Tender Number: Tenderer s Authorised Signatory: Name in block letters Signature Full name of company:

10 PAGE 10 OF 16 Technical schedules A and B For Plain Mast Dis1 Deviation schedule Any deviations offered to this specification shall be listed below with reasons for deviation. In addition, evidence shall be provided that the proposed deviation will at least be more cost-effective than that specified by City Power. Item Clause Proposed deviation Tender Number: Tenderer s Authorised Signatory: Name in block letters Signature Full name of company:

11 PAGE 11 OF 16 Technical schedules A and B For Plain Mast Dis3 Schedule A: Purchaser's specific requirements Schedule B: Guarantees and technical particulars of equipment offered Item Sub-clause of CP_TSSPEC_ 032 Description Schedule A Schedule B 1 Name of manufacturer XXXX 2 Place of manufacture XXXX 3 Manufacturer s identification reference Dis Standard to which mast complies SANS Does the design of the mast comply with all the requirements of SABS 0225 and this specification? Is the mast design approved and certified by a qualified professional structural engineer? Standard to which steel tubes comply SANS Material of mast Grade 300W steel Is the mast design accompanied by comprehensive strength calculations? Standard to which welding complies SANS Standard to which galvanising complies SANS ISO Mass of mast kg XXXX Is the mast marked in accordance with the requirements of 4.6? Is all the information requested in supplied? 15 Calculated natural frequency of mast Hz XXXX 16 Expected service life of mast years 30 (min) Tender Number: Tenderer s Authorised Signatory: Name in block letters Signature Full name of company:

12 PAGE 12 OF 16 Technical schedules A and B For Plain Mast Dis3 Deviation schedule Any deviations offered to this specification shall be listed below with reasons for deviation. In addition, evidence shall be provided that the proposed deviation will at least be more cost-effective than that specified by City Power. Item Clause Proposed deviation Tender Number: Tenderer s Authorised Signatory: Name in block letters Signature Full name of company:

13 PAGE 14 OF 16 Technical schedules A and B For Stay Pedestal Schedule A: Purchaser's specific requirements Schedule B: Guarantees and technical particulars of equipment offered Item Sub-clause of CP_TSSPEC_ 032 Description Schedule A Schedule B 1 Name of manufacturer XXXX 2 Place of manufacture XXXX 3 Manufacturer s identification reference STAY PEDESTAL Standard to which pedestal complies SANS Does the design of the pedestal comply with all the requirements of SABS 0225 and this specification? Is the pedestal design approved and certified by a qualified professional structural engineer? Standard to which steel tubes comply SANS Material of pedestal Grade 300W steel Is the pedestal design accompanied by comprehensive strength calculations? Standard to which welding complies SANS Standard to which galvanising complies SANS ISO Mass of pedestal kg XXXX Is the pedestal marked in accordance with the requirements of 4.6? Is all the information requested in supplied? 15 Calculated natural frequency of pedestal Hz XXXX 16 Expected service life of pedestal years 30 (min) Tender Number: Tenderer s Authorised Signatory: Name in block letters Signature Full name of company:

14 PAGE 14 OF 16 Technical schedules A and B For Stay Pedestal Deviation schedule Any deviations offered to this specification shall be listed below with reasons for deviation. In addition, evidence shall be provided that the proposed deviation will at least be more cost-effective than that specified by City Power. Item Clause Proposed deviation Tender Number: Tenderer s Authorised Signatory: Name in block letters Signature Full name of company:

15 SPECIFICATION FOR STEEL DISTRIBUTION POLES REFERENCE REV CP_TSSPEC_033 0 PAGE 15 OF 15 Annex D Stock Items Specification number: CP_TSSPEC_033 Material Group: POLE-SDST Item SAP number SAP Short Description SAP Long Description POLE STEEL Dis1 POLE, STEEL, STRAIGHT, 9,2 M, 8 M MOUNTING HEIGHT, REFERENCE Dis1. ITEM SPECIFICATION CP_TSSPEC_ POLE STEEL Dis3 POLE, STEEL, STRAIGHT, 10,7 M, 9,5 M MOUNTING HEIGHT, REFERENCE Dis3. ITEM SPECIFICATION CP_TSSPEC_ STAY PEDESTAL STAY PEDESTAL, STRAIGHT, 4,3 M, 190 MM MINIMUM DIAMETER, WITH PROVISION FOR CONNECTION OF STAY WIRE. ITEM SPECIFICATION CP_TSSPEC_033.