1、BRITISH STANDARD BS 215-2:1970 Specification for Aluminium conductors and aluminium conductors, steel-reinforced For overhead power transmission Part 2: Aluminium conductors, steel-reinforced UDC 621.315.55:669.71BS215-2:1970 This British Standard, having been approved by the Non-ferrous Metals Indu
2、stry Standards Committee, was published under the authority ofthe Executive Board on 31 March 1970 BSI 03-1999 First published, October, 1925 First revision, January, 1930 Second revision, March, 1934 Third revision, December, 1956 Fourth revision, March 1970 The following BSI references relate to t
3、he work on this standard: Committee reference NFE/24 Draft for comment 68/29132 ISBN 580 05769 0 Co-operating organizations The Non-ferrous Metals Industry Standards Committee, under whose supervision this British Standard was prepared, consists of representatives from the following Government depar
4、tments and scientific and industrial organizations: Aluminium Federation* Institution of Production Engineers Association of Bronze and Brass Founders Institution of Structural Engineers Association of Consulting Engineers Lead Development Association Board of Trade Light Metal Founders Association
5、British Bronze and Brass Ingot Manufacturers Association London Metal Exchange British Electrical and Allied Manufacturers Association* Magnesium industry Council British Lead Manufacturers Association Ministry of Defence, Army Department British Non-ferrous Metals Federation Ministry of Defence. Na
6、vy Department British Non-ferrous Metals Federation High Conductivity Copper Group National Brassfoundry Association British Non-ferrous Metals Research Association Non-ferrous Metal Stockists* Copper Development Association Post Office* Crown Agents for Overseas Governments and Administrations Roya
7、l Institute of British Architects Electric Cable Makers Confederation* Society of Motor Manufacturers and Traders Ltd. Institute of British Foundrymen Tin Research Institute Institute of Metals Zinc Development Association Institution of Mechanical Engineers (Automobile Division) Individual manufact
8、urer Institution of Mining and Metallurgy The Government department and scientific and industrial organizations marked with an asterisk in the above list, together with the following, were directly represented on the committee entrusted with the preparation of this British Standard: British Railways
9、 Board Institute of iron previously the requirements for steel-cored aluminium conductors were included together with those for aluminium stranded conductors now covered by BS215-1 in the one publication. In this revision all dimensions are included in metric units and the requirements of the standa
10、rd have been amended to conform substantially with those of I.E.C. Publication209, “Aluminium conductors, steel-reinforced”. As a result there are a number of changes in the specification. Throughout the term “aluminium conductor, steel-reinforced”, has been adopted in preference to the earlier “ste
11、el-cored aluminium conductor” as the former is now in more general use. Lay ratio is now defined as the ratio of the axial length of a complete turn of the helix to the external diameter of the helix instead of to the mean diameter of the helix as hitherto. The basis for calculating conductor breaki
12、ng loads has also been amended, the strength of the steel component now being based on the stress at1% elongation of the steel wires, which has been made a requirement for the steel wires. Values of the moduli of elasticity quoted in an Appendix are practical values obtained by test, which are consi
13、dered to be of more practical significance than the calculated values formerly quoted. In the course of metrication the sizes of standard conductors, of which the number has been restricted, have been maintained unchanged except for negligible differences due to the expression of wire diameters in m
14、illimetres. The sizes of conductors are designated by nominal aluminium areas (mm 2 ) in place of the formerly used nominal copper areas (in 2 ). For convenience the nominal aluminium areas have been taken as being numerically1000 times the previous nominal copper areas. At the present time there is
15、 an increasing use of conductors of constructions other than those covered in this standard. To facilitate standardization of these constructions lay ratio limits and the appropriate stranding factors are included in an appendix. Detailed requirements for aluminium and steel wires are not included i
16、n this standard but are specified in BS2627 1)and BS4565 2)respectively. All stresses are quoted in terms of the hectobar (hbar) 3) . Other British Standards dealing with aluminium conductors for overhead lines are listed below: BS 215, Aluminium conductors and aluminium conductors, steel-reinforced
17、 for overhead power transmission. BS 215-1, Aluminium stranded conductors. BS 3242, Aluminium alloy stranded conductors for overhead power transmission. In order to keep abreast of progress in the industries concerned, British Standards are subject to periodical review. Suggestions for improvements
18、will be recorded and in due course brought to the notice of the committees charged with the revision of the standards to which they refer. A complete list of British Standards, numbering over 5000, fully indexed and with a note of the contents of each, will be found in the British Standards Yearbook
19、. The BS Yearbook may be consulted in many public libraries and similar institutions. This standard makes reference to the following British Standards: BS 205, Glossary of terms used in electrical engineering. 1) BS 2627, “Wrought aluminium for electrical purposes. Wire”. 2) BS4565, “Galvanized stee
20、l wire for aluminium conductors, steel-reinforced”. 3) 1 hbar = 10 MN/m 2= 10 N/mm 2 .BS215-2:1970 BSI 03-1999 iii BS 2627, Wrought aluminium for electrical purposes. Wire. BS 4565, Galvanized steel wire for aluminium conductors, steel-reinforced. A British Standard does not purport to include all t
21、he necessary provisions of a contract. Users of British Standards are responsible for their correct application. Compliance with a British Standard does not of itself confer immunity from legal obligations. Summary of pages This document comprises a front cover, an inside front cover, pages i to iv,
22、 pages 1 to 8, an inside back cover and a back cover. This standard has been updated (see copyright date) and may have had amendments incorporated. This will be indicated in the amendment table on theinside front cover.iv blankBS215-2:1970 BSI 03-1999 1 1 General 1.1 Scope Part 2 of this British Sta
23、ndard applies to aluminium conductors, steel-reinforced for overhead power transmission. 1.2 Definitions For the purposes of this Part of this British Standard the following definitions apply. aluminium conductor, steel-reinforced a conductor consisting of seven or more aluminium and galvanized stee
24、l wires built up in concentric layers. The centre wire or wires are of galvanized steel and the outer layer or layers of aluminium diameter the mean of two measurements at right angles taken at the same cross section direction of lay the direction of lay is defined as right-hand or left-hand. With r
25、ight-hand lay, the wires conform to the direction of the central part of the letter Z when the conductor is held vertically. With left-hand lay, the wires conform to the direction of the central part of the letter S when the conductor is held vertically lay ratio the ratio of the axial length of a c
26、omplete turn of the helix formed by an individual wire in a stranded conductor to the external diameter of the helix for other definitions reference should be made to BS205 4) 1.3 Standards for hard-drawn aluminium wires 1.3.1 Resistivity. The resistivity of aluminium wire depends upon its purity an
27、d its physical condition. For the purposes of this British Standard, the maximum value permitted is2.8264 47 cm at20C, and this value shall also be used as the standard resistivity for the purpose of calculation. 1.3.2 Density. At a temperature of 20C the density of hard-drawn aluminium wire is to b
28、e taken as 2.703g/cm 3 . 1.3.3 Coefficient of linear expansion. The coefficient of linear expansion of hard-drawn aluminium is to be taken as23 10 6 /C. 1.3.4 Constant-mass temperature coefficient. At a temperature of20C the “constant mass” temperature coefficient of resistance of hard-drawn alumini
29、um wire, measured between two potential points rigidly fixed to the wire, is taken as0.00403/C. 1.4 Standards for galvanized steel wire 1.4.1 Density. At a temperature of 20C, the density of galvanized steel wire is to be taken as7.80g/cm 3 . 1.4.2 Coefficient of linear expansion. In order to obtain
30、 uniformity in calculations, a value of11.5 10 6 / C may be taken as the value for the coefficient of linear expansion of galvanized steel wires used for the cores of aluminium conductors, steel-reinforced. 2 Material The aluminium wires used in the construction of the conductor shall be material G1
31、E in the H9 condition as specified in BS2627 5) . The galvanized steel wires shall be of the standard tensile strength grade given in BS4565 6)unless one of the higher tensile strength grades is specified by the purchaser. By agreement between the purchaser and the manufacturer a suitable grease may
32、 be applied to the centre wire, or additionally to wires in specific layers, evenly throughout the length of the conductor. 3 Dimensions and construction 3.1 Standard sizes of wires The aluminium and steel wires for the standard constructions covered by this specification shall have the diameters sp
33、ecified inTable 2 and Table 3 respectively. The diameters of the steel wires shall be measured over the zinc coating. 3.2 Standard sizes of aluminium conductors, steel-reinforced 3.2.1 The sizes of standard aluminium conductors, steel-reinforced are given inTable 4. 3.2.2 The masses (excluding the m
34、ass of grease for corrosion protection) and resistances may be taken as being in accordance withTable 4. 4) BS 205, “Glossary of terms used in electrical engineering”. 5) BS 2627, “Wrought aluminium for electrical purposes. Wire”. 6) BS4565, “Galvanized steel wire for aluminium conductors, steel-rei
35、nforced”BS215-2:1970 2 BSI 03-1999 3.3 Joints in wires 3.3.1 Aluminium wires. In aluminium conductors, steel-reinforced, containing any number of aluminium wires, joints in individual aluminium wires are permitted, in addition to those made in the base rod or wire before final drawing, but no two su
36、ch joints shall be less than15m apart in the complete stranded conductor. Such joints shall be made by resistance or cold-pressure butt-welding. They are not required to fulfil the mechanical requirements for unjointed wires. Joints made by resistance butt-welding shall, subsequent to welding, be an
37、nealed over a distance of at least200mm on each side of the joint. 3.3.2 Galvanized steel wires. There shall be no joints, except those made in the base rod or wire before final drawing, in steel wires forming the core of an aluminium conductor, steel-reinforced, unless the core consists of seven or
38、 more galvanized steel wires. In the latter case joints in individual wires are permitted, in addition to those made in the base rod or wire before final drawing, but no two such joints shall be less than 15m apart in the complete steel core. Joints in galvanized steel wires shall be made by resista
39、nce butt-welding and shall be protected against corrosion. 3.4 Stranding 3.4.1 The wires used in the construction of an aluminium conductor, steel-reinforced shall, before stranding, satisfy all the relevant requirements of this standard. 3.4.2 The lay ratio of the different layers shall be within t
40、he limits given inTable 1. NOTEIt is important to note that lay ratio is now defined as the ratio of the axial length of a complete turn of the helix formed by an individual wire in a stranded conductor to the external diameter of the helix. 3.4.3 In all constructions, the successive layers shall ha
41、ve opposite directions of lay, the outermost layer being right-handed. The wires in each layer shall be evenly and closely stranded. 3.4.4 In conductors having multiple layers of aluminium wires, the lay ratio of any aluminium layer shall be not greater than the lay ratio of the aluminium layer imme
42、diately beneath it. 3.4.5 Steel wires shall be formed during stranding so that they remain inert when the conductor is cut. 3.5 Completed conductor The completed conductor shall be free from dirt, grit, excessive amounts of drawing oil and other foreign deposits. Table 1 Lay ratios for aluminium con
43、ductors, steel-reinforced 1 2 3 4 5 6 7 8 9 10 11 12 13 Number of wires Ratio aluminium wire diameter to steel wire diameter Lay ratios for steel core Lay ratios for aluminium layers 6-wire layer 12-wire layer 18-wire layer 24-wire layer Aluminium Steel min. max. min. max. min. max. min. max. min. m
44、ax. 6 6 12 1 7 7 1.000 3.000 1.000 13 13 28 28 10 10 14 14 10 14 18 30 54 1 7 7 1.000 1.000 1.000 13 13 28 28 10 16 10 10 10 14 16 17 10 10 14 16 10 14BS215-2:1970 BSI 03-1999 3 4 Tests 4.1 Selection of test samples 4.1.1 Samples for the tests specified in4.3 shall be taken by the manufacturer befor
45、e stranding, from not less than 10% of the individual lengths of aluminium and galvanized steel wire which will be included in any one consignment of stranded conductor. One sample, sufficient to provide one test specimen for each of the appropriate tests, shall be taken from each of the selected le
46、ngths of wire. 4.1.2 Alternatively, when the purchaser states at the time of ordering that he desires tests to be made in the presence of his representative, samples of wire shall be taken from lengths of stranded conductor selected from approximately10% of the lengths included in any one consignmen
47、t. One sample, sufficient to provide one specimen for each of the appropriate tests, shall be taken from each of an agreed number of wires of the conductor in each of the selected lengths. 4.2 Place of testing Unless otherwise agreed between the purchaser and the manufacturer at the time of ordering
48、, all tests shall be made at the manufacturers works. 4.3 Tests 4.3.1 Aluminium wires. The test samples of aluminium wires taken under4.1.1 shall be subjected to the following tests in accordance with BS2627 7)and shall meet the requirements of that standard: Tensile test. Wrapping test. Resistivity
49、 test. Test samples of aluminium wires taken under4.1.2 shall be subjected to the same tests but in the case of the tensile test the tensile strength of the specimen shall be not less than95% of the appropriate minimum value specified in BS2627 7) . 4.3.2 Steel wires. The test samples of galvanized steel wires taken under4.1.1 shall be subjected to the following tests in accordance with BS4565 8)and shall meet the requirements of that standard. Determination of stress at 1% elongation. Tensile te
