TABLE OF CONTENTS. Page FOREWORD INTRODUCTION SCOPE NORMATIVE REFERENCES

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1 TITLE SPECIFICATION FOR STAYS AND REFERENCE DATE: PAGE: 1 REV 1 APRIL 2009 OF 16 TABLE OF CONTENTS Page FOREWORD INTRODUCTION SCOPE NORMATIVE REFERENCES DEFINITIONS AND ABBREVIATIONS REQUIREMENTS General Stay wire Stay anchor assemblies Stay insulators Thimbles Stay brackets (Straps) Guy grip dead-end fittings Double wrap guy grip Stay guards TESTS MARKING, LABELLING AND PACKAGING DOCUMENTATION TRAINING

2 PAGE 2 OF 16 9 QUALITY ASSURANCE ENVIRONMENTAL MANAGEMENT... 8 Annex A Bibliography... 9 Annex B Revision information Annex C Technical schedules A and B (MV) Annex C - Technical schedules A and B (LV) Annex D Stock Items... 15

3 PAGE 3 OF 16 FOREWORD Recommendations for corrections, additions or deletions should be addressed to the: Technology Services Manager City Power Johannesburg (Pty) Ltd P O Box Booysens 2016

4 PAGE 4 OF 16 INTRODUCTION Stays and associated components are widely used on City Power s overhead networks to support pole structures at line deviations and end poles and form an integral part of these overhead networks. These components are installed outdoors and are exposed to hostile weather conditions. Stays and associated components need to meet the specified technical requirements to sustain their performance and the life expectancy of the network. 1 SCOPE The purpose of this specification is to detail the technical requirements to be met when acquiring stays and associated components for use on City Power s overhead networks. 2 NORMATIVE REFERENCES The following documents contain provisions that, through reference in the text, constitute requirements of this specification. 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. NRS 022, Stays and associated components 3 DEFINITIONS AND ABBREVIATIONS The definitions and abbreviations in the above document shall apply to this specification. 4 REQUIREMENTS 4.1 General Stays and associated components shall comply with the requirements of NRS Nothing in this specification shall lessen the obligations of the supplier. The supplier shall be fully responsible for the design and its satisfactory performance in service. Acceptance by City Power shall not relieve the supplier of the responsibility for the adequacy of the design. 4.2 Stay wire The standard stay wire to be supplied shall be of the following constructions as per the requirement of NRS 022: Number and diameter of wires Nominal tensile grade of the wire steel Minimum breaking load of stay wire Maximum safe working load of stay wire (Factor of safety 2,5) Breaking load of stay insulator 3/3.35 mm 1100MPa kn kn 34 kn 7/3,35 mm 1100 MPa 67,452 kn 26,981 kn 70 kn Table 1 Mechanical strength of the stay wire

5 PAGE 5 OF Stay anchor assemblies Only an assembly comprising the following components as per the requirement of NRS 022 shall be supplied: Components MV LV Stay rod 20 mm x 2 m 12 mm x 1.5 m Stay plate 375 mm x 375 mm x 6 mm 300 mm x 300 mm x 6 mm Table 2 Dimensions of the stay rod and stay plate Material: Hot dipped galvanised, 300W steel grade. FOR USE ON MV SYSTEMS AND LV BARE FOR USE ON LV ABC WIRE SYSTEMS Picture 1 Stay anchor assemblies 4.4 Stay insulators The stay insulator material shall be glazed porcelain. An alternative composite material may be used provided it can be demonstrated that it meets the minimum required mechanical and electrical performance, and has a similar service lifespan to that of a porcelain insulator. Picture 2 Stay insulator

6 PAGE 6 OF 16 The standard stay insulators to be supplied shall be of the following construction: Electrical and Mechanical characteristics. Type of stay insulator Dry withstand voltage Wet withstand voltage Leakage distance Breaking load of stay insulator Porcelain (LV) 25 kv 11 kv 60 mm 34 kn Porcelain (MV) 38 kv 22 kv 76 mm 70 kn Table 3 Electrical and mechanical characteristics 4.5 Thimbles Thimbles shall comply with the requirements of NRS 022 and shall have a long-term performance equal to other fittings specified in this specification Material: Hot dipped galvanised, 300W steel grade Thimble shall have an opening suitable to fit 14 mm diameter stay wire. Picture 3 Thimbles 4.6 Stay brackets (Straps) Stay brackets shall comply with the requirements of NRS 022 and shall have a long-term performance equal to other fittings specified in this specification. Picture 4 Stay bracket and Thimble assembly

7 PAGE 7 OF Material: Hot dipped galvanised, 300W steel grade Dimensions: Flat bar 60 mm (Width) x 16 mm (Thickness) One end surface offset with 22 mm diameter fixing hole Other end length 60 mm with 25 mm diameter hole. 4.7 Guy grip dead-end fittings Guy grip dead ends shall comply with the requirements of NRS 022 and shall have a longterm performance equal to other fittings specified in this specification Material: Hot dipped galvanised, 300W steel grade Hot dipped galvanised, approximately 660mm long for 3/3.35 mm stay wire Hot dipped galvanised, approximately 960mm long for 7/3.35 mm stay wire. Picture 5 Thimble 4.8 Double wrap guy grip Double wrap guy grips shall comply with the requirements of NRS 022 and shall have a longterm performance equal to other fittings specified in this specification Galvanised steel wire with a diameter of 7.21 mm for 3/3.35 mm stay wire Galvanised steel wire with a diameter of 12 mm for 7/3.35 mm stay wire. Picture 6 Double wrap guy grip and stay wire assembly

8 PAGE 8 OF Stay guards Only stay guards of the PVC clip-on type that comply with the requirements of NRS 022 shall be supplied. The stay guards shall be painted yellow and shall be a minimum of 2m in length. 5 TESTS Tests on stays and associated components shall comply with the requirements of NRS MARKING, LABELLING AND PACKAGING Marking, labelling and packaging shall comply with the requirements of NRS DOCUMENTATION Documentation that complies with the requirements of NRS 022 shall be submitted in a catalogue format. In addition, relevant test certificates confirming compliance with the requirements of NRS 022 shall be submitted. 8 TRAINING 8.1 A necessary certified training course shall be offered to relevant City Power staff. The training shall include handling, storage and installation of stays and associated components. 8.2 The associated costs for the certified training course in 8.1 shall be given per person and shall be fixed for the period of the contract. 9 QUALITY ASSURANCE A quality management plan shall be set up in order to assure the proper quality management of stays and associated components during design, development, production and installation. Guidance on the requirements for a quality management plan may be found in the ISO The details shall be subject to agreement between City Power and supplier 10 ENVIRONMENTAL MANAGEMENT An environmental management plan shall be set up in order to assure the proper environmental management of stay and associated components throughout their entire life cycle (i.e. during design, development, production and installation. Guidance on the requirements for an environmental management system may be found in ISO standards. The details shall be subject to agreement between City Power and supplier. This is to ensure that the asset created conforms to environmental standards and City Power SHER Policy.

9 PAGE 9 OF 16 Annex A Bibliography Eskom specification DSP0017 Specification for stay insulators porcelain or equivalent used for medium and low voltage overhead. Eskom standard DST_ Light conductors particular requirements for overhead lines up to 33kV with conductors up to Hare conductor

10 PAGE 10 OF 16 Annex B Revision information DATE REV. NO. NOTES Aug First issue April Update committee members Inclusion of tables 1 to 3 Inclusion of pictures 1 to 6 Inclusion of clause 4.5 Inclusion of clause 4.6 Inclusion of clause 4.7 Inclusion of clause 4.8 Update of technical schedules General editing

11 PAGE 11 OF 16 Annex C Technical schedules A and B (MV) for Stays and associated components (Medium Voltage) Schedule A: Purchaser's specific requirements Schedule B: Guarantees and technical particulars of equipment offered Item Sub-clause Description Schedule A Schedule B Manufacturing standard NRS 022 XXXX Stay wires XXXX XXXX Number and diameter of wires mm 7/3.35 Breaking load of stay wire kn Stay anchor assemblies XXXX XXXX Stay rod mm x m 20 x 2 Stay plate (6mm) mm x mm 375 x 375 Stay insulators XXXX XXXX Type of insulator Material Porcelain Breaking load kn Thimbles XXXX XXXX Suitable for diameter stay wire mm 14 Stay brackets (Straps) XXXX XXXX Dimensions mm x mm 60 x 16 Diameter fixing hole mm 22 Guy grip dead end XXXX XXXX Length mm ±960 Double wrap guy grip XXXX XXXX Diameter mm 12 Stay guards Clip-on Type tests certificates results required Yes/No Yes XXXX Marking and packing as per NRS 022? Yes/No Yes Details of installation instructions required? Yes/No Yes 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 Stays and associated components (Medium Voltage) 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 costeffective than that specified by City Power. Item Sub-clause Proposed deviation Tender Number: Tenderer s Authorised Signatory: Name in block letters Signature Full name of company:

13 PAGE 13 OF 16 Annex C - Technical schedules A and B (LV) for Stays and associated components (Low Voltage) Schedule A: Purchaser's specific requirements Schedule B: Guarantees and technical particulars of equipment offered Item Sub-clause Description Schedule A Schedule B Manufacturing standard NRS 022 XXXX Stay wires XXXX XXXX Number and diameter of wires mm 3/3.35 Breaking load of stay wire kn Stay anchor assemblies XXXX XXXX Stay rod mm x m 12 x 1.5 Stay plate (6mm) mm x mm 300 x 300 Stay insulators XXXX XXXX Type of insulator Material Porcelain Breaking load kn Thimbles XXXX XXXX Suitable for diameter stay wire mm 14 Stay brackets (Straps) XXXX XXXX Dimensions mm x mm 60 x 16 Diameter fixing hole mm 22 Guy grip dead end XXXX XXXX Length mm ±660 Double wrap guy grip XXXX XXXX Diameter mm 7.21 Stay guards Clip-on Type tests certificates results required Yes/No Yes XXXX Marking and packing as per NRS 022? Yes/No Yes Details of installation instructions required? Yes/No Yes 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 Stays and associated components (Low Voltage) 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 costeffective than that specified by City Power. Item Sub-clause Proposed deviation Tender Number: Tenderer s Authorised Signatory: Name in block letters Signature Full name of company:

15 PAGE 15 OF 16 Annex D Stock Items Material Group: NET-ACCS Item SAP No. SAP Short Description SAP Long Description STAY WIRE, GALV, 7/3.35MM STAY WIRE, HOT-DIP GALVANISED, HAVING SEVEN (7) STRANDS OF 3.35MM DIAMETER, 1100MPA NOMINAL TENSILE GRADE OF THE WIRE STEEL, KN MINIMUM BREAKING LOAD. ITEM SPECIFICATION NO STAY WIRE, GALV, 3/3.35MM STAY WIRE, HOT-DIP GALVANISED, HAVING SEVEN (3) STRANDS OF 3.35MM DIAMETER, 1100MPA NOMINAL TENSILE GRADE OF THE WIRE STEEL, KN MINIMUM BREAKING LOAD. ITEM SPECIFICATION NO STAY ROD, GALV, 2MX20MM STAY ROD, HOT-DIP GALVANISED, 300W STEEL GRADE, 2M LENGTH, 20MM DIAMETER. ITEM SPECIFICATION NO STAY ROD, GALV, 1.5MX12MM STAY ROD, HOT-DIP GALVANISED, 300W STEEL GRADE, 1.5M LENGTH, 12MM DIAMETER. ITEM SPECIFICATION NO STAY PLATE, 375 X 375 X 6MM STAY PLATE, HOT-DIP GALVANISED, 300W STEEL GRADE, 375MM X 375MM DIMENSIONS. ITEM SPECIFICATION NO STAY PLATE, 300 X 300 X 6MM STAY PLATE, HOT-DIP GALVANISED, 300W STEEL GRADE, 300MM X 300MM DIMENSIONS. ITEM SPECIFICATION NO STAY INSUL, PORC, 70KN STAY INSULATOR, PORCELAIN, 70KN BREAKING LOAD, 76MM LEAKAGE DISTANCE, ITEM SPECIFICATION NO STAY INSUL, PORC, 34KN STAY INSULATOR, PORCELAIN, 34KN BREAKING LOAD, 60MM LEAKAGE DISTANCE, ITEM SPECIFICATION NO THIMBLE GALV THIMBLE, HOT-DIP GALVANISED. ITEM SPECIFICATION NO STAY BRACKET (STRAP) STAY BRACKET (STRAP), HOT-DIP GALVANISED, 300W STEEL GRADE. ITEM SPECIFICATION NO GUY GRIP, D/END, GALV, 7/3.35MM GUY GRIP PREFORMED DEAD-END FITTINGS, HOT-DIP GALVANISED, COMMENSURATE WITH 7/3.35 GALVANISED STAY WIRE. ITEM SPECIFICATION NO GUY GRIP, D/END, GALV, 3/3.35MM GUY GRIP PREFORMED DEAD-END FITTINGS, HOT-DIP GALVANISED, COMMENSURATE WITH 3/3.35 GALVANISED STAY WIRE. ITEM SPECIFICATION NO DOUBLE WRAP GUY GRIP, GALV, 7/4MM DOUBLE WRAP GUY GRIP, GALV, 3/3.35MM GUY GRIP, DOUBLE WRAP, 12MM DIAMETER GALVANISED STEEL, COMMENSURATE WITH 7/4MM STAY WIRE. ITEM SPECIFICATION NO. GUY GRIP, DOUBLE WRAP, 7.21MM DIAMETER GALVANISED STEEL, COMMENSURATE WITH 3/3.35MM STAY WIRE. ITEM SPECIFICATION NO STAY GUARD, CLIP-ON, PVC STAY GUARD, CLIP-ON TYPE, POLYVINYLCHLORIDE (PVC), 2M IN LENGTH, PAINTED YELLOW. ITEM SPECIFICATION NO.

16 PAGE 16 OF STAY KIT COMPLETE (MV) STAY KIT COMPLETE (MV). (STAY ANCHOR ASSEMBLY, THIMBLE, GUY GRIP, STAY WIRE, STAY INSULATOR, STAY STRAP), ITEM SPECIFICATION NO STAY KIT COMPLETE (LV) STAY KIT COMPLETE (LV), (STAY ANCHOR ASSEMBLY, THIMBLE, GUY GRIP, STAY WIRE, STAY INSULATOR, STAY STRAP), ITEM SPECIFICATION NO.