oSIST prEN IEC 63248:2021

SLOVENSKI STANDARD
oSIST prEN IEC 63248:2021
01-julij-2021
Vodniki za nadzemne vode - Prevlečena ali oblečena kovinska žica za
koncentrične laične vodnike

Conductors for overhead lines - Coated or cladded metallic wire for concentric lay

2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

SUBMITTED FOR CENELEC PARALLEL VOTING NOT SUBMITTED FOR CENELEC PARALLEL VOTING

This document is still under study and subject to change. It should not be used for reference purposes.

Recipients of this document are invited to submit, with their comments, notification of any relevant patent rights of which

Conductors for overhead lines - Coated or cladded metallic wire for concentric lay stranded

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3 FOREWORD ........................................................................................................................... 4

4 INTRODUCTION ..................................................................................................................... 6

5 1 Scope .............................................................................................................................. 7

6 2 Normative references ...................................................................................................... 7

7 3 Terms and definitions ...................................................................................................... 7

8 4 Material ........................................................................................................................... 9

9 4.1 Steel ....................................................................................................................... 9

10 4.2 Aluminium ............................................................................................................... 9

11 4.3 Zinc ........................................................................................................................ 9

12 4.4 Zinc-aluminium alloy ............................................................................................... 9

13 4.5 Advanced zinc-aluminium alloy ............................................................................... 9

14 5 Freedom from defects ...................................................................................................... 9

15 6 Joints .............................................................................................................................. 9

16 7 Tests ............................................................................................................................. 10

17 7.1 General ................................................................................................................. 10

18 7.2 Place of testing ..................................................................................................... 10

19 7.3 Sampling rate ....................................................................................................... 10

20 7.4 Test methods ........................................................................................................ 10

21 7.4.1 Visual test ..................................................................................................... 10

22 7.4.2 Diameter ........................................................................................................ 10

23 7.4.3 Stress at 1% extension, tensile strength and elongation ................................ 11

24 7.4.4 Ductility tests ................................................................................................. 12

25 7.4.5 Coating or cladding tests ............................................................................... 13

26 7.4.6 Coefficient of linear expansion ....................................................................... 14

27 7.4.7 Resistivity ...................................................................................................... 14

28 7.4.8 Coating adherence heat resistance test ......................................................... 14

29 8 Acceptance and rejection .............................................................................................. 15

30 9 Certificate of compliance ............................................................................................... 15

31 10 Packaging ..................................................................................................................... 15

32 10.1 Type of packaging ................................................................................................ 15

33 10.2 Length and tolerance on length ............................................................................. 15

34 Annex A (normative) Tables of properties for recommended IEC wire materials .................. 16

35 Annex B (informative) Properties of wire for calculation purposes ....................................... 32

36 Annex C (informative) Method to measure the equivalent diameter by volume .................... 34

37 Annex D (informative) Ratio of aluminium and steel or FeNi36 cross-sectional areas .......... 36

38 Bibliography .......................................................................................................................... 38

40 Figure C.1 – OPGW composed of a formed aluminium-clad steel wires ................................. 34

41 Figure C.2 – Density measurement apparatus for example ................................................... 34

43 Table A.1 – Wire designation ................................................................................................ 16

44 Table A.2 – Schedule of tests ............................................................................................... 17

45 Table A.3 – Zinc-aluminium alloy ingot composition (group 4 and group 5) ........................... 18

46 Table A.4 – Requirements for zinc and zinc-aluminium alloy coated steel wires (group

47 1, group 4 and group 5) ........................................................................................................ 19

48 Table A.5 – Requirements for aluminium-clad FeNi36 wires (group 2) ................................... 23

49 Table A.6 – Requirements for aluminium-clad steel wires (group 3) ...................................... 25

50 Table A.7 – Initial setting for determining stress at 1% extension .......................................... 28

51 Table A.8 – Coating requirements for zinc and zinc-aluminium alloy coated wires ................. 29

52 Table A.9 – Cladding requirements for Group 2 and Group 3 wire ......................................... 30

53 Table A.10 – Coating heat resistance test for Group 4 and Group 5 wire .............................. 30

54 Table A.11 – Temperatures for linear expansion test for Group 2 wire .................................. 31

55 Table A.12 – Minimum number of dips for Zn and Zn Alloy coatings (group 1, group 4,

56 group 5) ................................................................................................................................ 31

57 Table B.1 – Properties of wire for calculation purposes ......................................................... 32

58 Table D.1 – Standard aluminium and steel or FeNi36 ratio in the cross section for

59 Group 2 and Group 3 wires ................................................................................................... 36

60 Table D.2 – Average aluminium thickness ............................................................................. 37

72 1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising

73 all national electrotechnical committees (IEC National Committees). The object of IEC is to promote international

74 co-operation on all questions concerning standardization in the electrical and electronic fields. To this end and

75 in addition to other activities, IEC publishes International Standards, Technical Specifications, Technical Reports,

76 Publicly Available Specifications (PAS) and Guides (hereafter referred to as “IEC Publication(s)”). Their

77 preparation is entrusted to technical committees; any IEC National Committee interested in the subject dealt with

78 may participate in this preparatory work. International, governmental and non-governmental organizations liaising

79 with the IEC also participate in this preparation. IEC collaborates closely with the International Organization for

80 Standardization (ISO) in accordance with conditions determined by agreement between the two organizations.

81 2) The formal decisions or agreements of IEC on technical matters express, as nearly as possible, an international

82 consensus of opinion on the relevant subjects since each technical committee has representation from all

84 3) IEC Publications have the form of recommendations for international use and are accepted by IEC National

85 Committees in that sense. While all reasonable efforts are made to ensure that the technical content of IEC

86 Publications is accurate, IEC cannot be held responsible for the way in which they are used or for any

88 4) In order to promote international uniformity, IEC National Committees undertake to apply IEC Publications

89 transparently to the maximum extent possible in their national and regional publications. Any divergence between

90 any IEC Publication and the corresponding national or regional publication shall be clearly indicated in the latter.

91 5) IEC itself does not provide any attestation of conformity. Independent certification bodies provide conformity

92 assessment services and, in some areas, access to IEC marks of conformity. IEC is not responsible for any

94 6) All users should ensure that they have the latest edition of this publication.

95 7) No liability shall attach to IEC or its directors, employees, servants or agents including individual experts and

96 members of its technical committees and IEC National Committees for any personal injury, property damage or

97 other damage of any nature whatsoever, whether direct or indirect, or for costs (including legal fees) and

98 expenses arising out of the publication, use of, or reliance upon, this IEC Publication or any other IEC

100 8) Attention is drawn to the Normative references cited in this publication. Use of the referenced publications is

102 9) Attention is drawn to the possibility that some of the elements of this IEC Publication may be the subject of patent

103 rights. IEC shall not be held responsible for identifying any or all such patent rights.

104 IEC 63248 has been prepared by IEC technical committee 7: OVERHEAD ELECTRICAL

106 This International Standard cancels and replaces IEC 61232:1993 Edition 1.0, and replaces

110 Full information on the voting for its approval can be found in the report on voting indicated in

112 The language used for the development of this International Standard is English.

113 This document was drafted in accordance with ISO/IEC Directives, Part 2, and developed in

114 accordance with ISO/IEC Directives, Part 1 and ISO/IEC Directives, IEC Supplement, available

115 at www.iec.ch/members_experts/refdocs. The main document types developed by IEC are

117 The committee has decided that the contents of this document will remain unchanged until the

118 stability date indicated on the IEC website under webstore.iec.ch in the data related to the

126 The purpose of this standard is to group together similar wire materials that share the same

127 general characteristics and therefore the same test procedures and requirements. Included in

128 this standard are existing wire types from IEC 60888 and IEC 61232 as well as new wire

129 materials that are already in use around the world in new types of conductors.

130 Zinc coating class 2 according to IEC 60888 has not been included in this standard, as the

131 demand for this class of zinc coating is extremely rare. Extra corrosion protection can be

140 This document specifies the properties of wires in the diameter range of, but not limited to, 1,25

141 mm to 5,50 mm. This standard is applicable to coated or cladded metallic wires before stranding

142 used either as concentric lay overhead stranded conductors, or in the manufacture of cores for

143 concentric lay overhead stranded conductors, for power transmission purposes.

144 The various wire types and their designations are listed in Table A.1. For calculation purposes

147 The following documents are referred to in the text in such a way that some or all of their content

148 constitutes requirements of this document. For dated references, only the edition cited applies.

149 For undated references, the latest edition of the referenced document (including any

154 ISO 6892-1, Metallic materials — Tensile testing — Part 1: Method of test at room

156 ISO 7500-1, Metallic materials — Verification of static uniaxial testing machines — Part 1:

157 Tension/compression testing machines — Verification and calibration of the force-

162 ISO 7989-2, Steel wire and wire products — Non-ferrous metallic coatings on steel wire —

165 For the purposes of this document, the terms and definitions given in IEC 60050 and the

167 ISO and IEC maintain terminological databases for use in standardization at the following

173 the result of a process by which a metal is bonded under high pressure by co-rolling, co-

177 a number attributed to aluminium-clad wires for the purpose of providing an approximate

181 the result of a process by which a metal is deposited onto a wire by hot-dip or electrolytic

185 the diameter of a round wire, which would have the same cross sectional area as a given formed

192 a designation given to wire types that share a common coating or cladding, or property for a

196 a grade of steel-nickel alloy designed to have a very low coefficient of thermal expansion

199 a group of production units of one type and size of wire, which was manufactured by the same

200 manufacturer during the same time period under similar conditions of production

204 the value of a measurable property to which tolerance is applied. Nominal values are target

208 a coil, reel, spool, or other package of wire that represents a single usable length

211 specimen or specimens removed from a production unit or units which is considered to have

218 a mixture of zinc and aluminium coating applied onto the wire for the purpose of protecting it

223 a zinc-aluminium alloy reaching specific requirements as specified in ISO7989-2

224 Note: Examples of advanced zinc-aluminium alloys are Zn90% + 10% aluminium and Zn95% + 5 % aluminium with

228 The base metal shall be steel produced by the open hearth, electric furnace, or basic oxygen

229 process and shall be of such composition that the finished wire shall have the properties and

232 The aluminium used for coating or cladding shall have a minimum purity of 99,5% and of

233 sufficient quality to meet thickness and electrical resistance requirements of this standard.

235 The ingot of zinc used for coating shall meet the requirements of ZN-3 according ISO 752.

236 The zinc coating shall be applied by either the hot-dip or electroplating method. Unless agreed

237 between the purchaser and the manufacturer, the method of coating shall be at the discretion

240 The ingot of zinc-aluminium alloy used for coating shall be in accordance with Table A.3.

242 The ingot of advanced zinc-aluminium alloy used for coating shall be in accordance with Table

245 The wires shall be smooth and free from all imperfections such as cracks, roughness, grooves,

246 inclusions and other defects which may compromise the performance of the final product.

249 Joints may be made at any stage of processing prior to final cold drawing by the electric butt-

251 Welding equipment and procedure shall be such that it can be demonstrated that the ultimate

252 tensile strength of a finished wire specimen containing the welded section shall be

254 A welded section shall meet all other requirements, except the stress at 1 % extension,

256 No joints are allowed after heat treatment on wires, which will be used in single wire conductors.

259 Tests shall be made by the manufacturer on the wires to demonstrate their conformance to this

263 Unless otherwise agreed between the purchaser and the manufacturer at time of ordering, all

266 Specimen for tests specified in clause 7.4 shall be taken by the manufacturer from samples of

268 Alternatively, if a quality assessment procedure is in place and implemented, the sampling rate

272 The surface of the wire shall be visually examined to ensure that it is smooth and free from all

273 imperfections including but not limited to cracks, unevenness, holes and inclusion of impurities.

276 The nominal diameter of a wire shall be expressed in millimetres to two decimal places.

278 The diameter of a round wire shall be the mean of two measurements at right angle taken at

279 the same cross-section. The measurement apparatus shall have an accuracy of at least 0,001

281 When tested in accordance with this sub clause the diameter shall not vary from its nominal

282 value by more than the appropriate value indicated in Table A.4, Table A.5, or Table A.6.

284 The equivalent diameter of a formed wire shall be obtained from weight measurements made

285 on a sample not less than 1,0 m in length, and its density as defined in Table B.1.

286 The equivalent diameter, D of the formed wire shall be calculated by the Formula (1).

287 D = (1)

293 When tested in accordance with this sub clause the equivalent diameter shall not vary from its

294 nominal value by more than the tolerance value indicated in Table A.4, Table A.5, or Table A.6.

296 Alternatively the equivalent diameter of a formed wire shall be obtained from volume and weight

298 When tested in accordance with this sub clause the equivalent diameter shall not vary from its

299 nominal value by more than the tolerance value indicated in Table A.4, Table A.5, or Table A.6.

302 The wire samples shall be free from bends or kinks other than the curvature resulting from the

303 usual coiling operation. It shall be straightened before inserting in the grips of the tensile testing

304 equipment with a roller type wire straightening arrangement or by any other means designed to

305 exert the minimum effect upon the mechanical properties of the sample. Samples for tests shall

306 not be less than 450 mm long and shall be fitted in the testing machine so as to leave a free

310 The force-measuring system of the testing machine shall be calibrated in accordance with ISO

312 The rate of separation of the jaws of the testing machine shall be between 25 mm/min and 100

314 In order to obtain a straight test piece and ensure the alignment of the test piece and grip

315 arrangement, a preliminary load corresponding with the initial stress in accordance with Table

317 This load shall be maintained while a 250 mm gauge is marked on the sample and a suitable

318 extensometer applied on a 250 mm gauge length (not necessarily corresponding with the

320 A correction of the extension, in accordance with Table A.7, should be carried out to take into

322 This load shall then be increased uniformly until the extensometer indicates an extension of 2,5

324 At this point the tensile testing equipment may be stopped if necessary, and the load read. The

325 value of stress at 1% extension is calculated by dividing this load by the area of the wire based

326 on wire diameter measurements as per clause 7.3.2. Following this operation, the extensometer

327 may be removed. The specimen shall then be loaded to rupture and its tensile strength

329 When tested in accordance with this sub clause the wire shall conform to the requirements

334 When tested in accordance with this sub clause the wire shall conform to the requirements

339 When tested in accordance with this clause the wire shall conform to the requirements

345 The number of torsions obtained shall not be less than the value given in Table A.4, Table A.5

349 The specimen shall be wrapped 8 turns in a close spiral around a mandrel, at a rate not

351 The mandrel diameter shall be in accordance with the value given in Table A.4, Table A.5, or

353 When tested in accordance with this clause, the sample shall not completely break.

356 The minimum number of reverse bends to be achieved shall be agreed between purchaser and

358 Note : to have a reference on the minimum achievable reverse bends one can refer to ISO 2232 Quality A.