1、BRITISH STANDARD BS419:1966 Specification for Varnished fabrics and tapes for electrical purposesBS419:1966 This BritishStandard, having been approved by the ElectricalIndustry Standards Committee and endorsed by theChairman of the EngineeringDivisional Council,was published undertheauthorityof the
2、GeneralCouncilon 5August1966 BSI01-2000 First published July1931 First revision July1956 Second revision August1966 The following BSI references relate to the work on this standard: Committee reference ELE/16/7 Draft for comment D64/5536 ISBN 0 580 00515 1 Co-operating organizations The Electrical I
3、ndustry Standards Committee under whose supervision this BritishStandard was prepared, consists of representatives from the following Government departments and scientific and industrial organizations: Associated Offices Technical Committee Electronic Engineering Association* Association of Consulti
4、ng Engineers Engineering Equipment Users Association Association of Mining Electrical and Independent Cable Makers Association Mechanical Engineers Institution of Electrical Engineers Association of Supervising Electrical Ministry of Aviation* Engineers Ministry of Defence, Army Department* British
5、Electrical and Allied Manufacturers Ministry of Defence, Navy Department* Association* Ministry of Labour (H.M. Factory British Railways Board Inspectorate) Cable Makers Association Ministry of Power Crown Agents for Oversea Governments and Ministry of Public Building and Works Administrations Munic
6、ipal Passenger Transport Association Electric Lamp Industry Council (Incorporated) Electric Light Fittings Association National Inspection Council for Electrical Electrical Contractors Association Installation Contracting (Incorporated) National Physical Laboratory (Ministry of Electrical Contractor
7、s Association of Technology) Scotland Oil Companies Materials Association Electrical Research Association* Post Office* Electricity Council, The Generating Board Public Transport Association (Incorporated) and the Area Boards in England South of Scotland Electricity Board and Wales* The Government d
8、epartments 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 BritishStandard: Association of Electrical Machinery Trades Tape Manufacturers Association
9、British Plastics Federation Telephone Manufacturers Technical Glass Textile Association Development Committee Radio and Electronic Component Manufacturers Federation Amendments issued since publication Amd. No. Date CommentsBS419:1966 BSI 01-2000 i Contents Page Co-operating organizations Inside fro
10、nt cover Foreword ii 1 Scope 1 2 Definitions 1 3 Designation 1 4 Quality 1 5 Thickness 1 6 Width 2 7 Length 2 8 Joins 2 9 Packaging 3 10 Electric strength (proof) 3 11 Other properties 3 12 Varnish stability 3 13 Extensibility 3 Appendix A Conditioning of test pieces 9 Appendix B Thickness 9 Appendi
11、x C Electric strength (one minute proof test) 9 Appendix D Tensile strength of varnished fabric 11 Appendix E Tearing strength of varnished fabric 12 Appendix F Change in tearing strength with heating in air 12 Appendix G Acidity 13 Appendix H Varnish stability 13 Appendix J Extensibility of tape 14
12、 Appendix K Confirmation of glass base fabric 14 Figure 1 Electrode apparatus for electric-strength test on tape 15 Figure 2 Apparatus for stretching and testing extended tape for electric strength 16 Figure 3 Stretching device combined with electrodes for testing extended tape for electric strength
13、 17 Figure 4 Test piece for tearing strength test showing tongue 18 Figure 5 General view of Marx-Elmendorf tearing-strength tester 18 Figure 6 Method of clamping test pieces in the Marx-Elmendorf tearing-strength tester 19 Table 1 Thickness 2 Table 2 Electric strength (one minute proof test) 4 Tabl
14、e 3 Other properties 6 Table 4 Minimum tensile strength (metric units) 7BS419:1966 ii BSI 01-2000 Foreword This standard makes reference to the following BritishStandards: BS870, External micrometers. BS2586, Glass electrodes. BS2757, Classification of insulating materials for electrical machinery a
15、nd apparatus on the basis of thermal stability in service. BS3218, Test tubes and boiling tubes. BS3502, List of common names and abbreviations for plastics. BS3718, Laboratory humidity ovens (non-injection type). The information on which this revision is based was provided by the Electrical Researc
16、h Association. Varnished fabrics for use as electrical insulation are made from a variety of base fabrics woven from cotton, silk, and man-made fibres including glass, and treated with varnishes of various types based on natural and synthetic resins, drying oils and other substances such as bitumen.
17、 Previous editions of this standard only dealt with varnished cotton fabrics but, in this revision, the opportunity has been taken to include fabrics woven from other materials. The standard gives requirements for two types of varnished fabric. The yellow varnished fabric is manufactured with a clea
18、r varnish, usually consisting of a drying oil in combination with a resin, and the black varnished fabric is manufactured with a varnish usually consisting of a drying oil in combination with a bitumen-based substance. The black varnished fabric has greater moisture resistance and higher electric st
19、rength than the yellow varnished fabric, but with the introduction of new materials the distinction is no longer so apparent. However, the designation of yellow or black varnished fabric is maintained because these names are common usage in industry. A system of designation has been included which w
20、ill assist in overcoming the apparent limitation imposed by the terms “yellow” and “black”. Varnished fabrics based on cotton, silk and nylon are suitable for insulation in windings and other parts of electrical apparatus for which the maximum operating temperature is105 C (Class A, BS2757 1) ). Fab
21、rics woven from polyethylene-terephthalate (PTP) 2)(e.g.Terylene) 3)and glass filament yarns and treated with the same varnishes as used on cotton, silk or nylon, may be suitable for use at120 C (Class E, BS2757 4) ). Glass fabric when varnished with special synthetic resin based varnishes is suitab
22、le for use at Class B 4) (130 C) or higher temperatures but in this revision only the minimum requirements for varnished glass fabrics are covered, and no attempt has been made to specify requirements for the more heat resistant grades. The tests detailed in this specification are not intended to as
23、sess the suitability of the various varnished fabrics for use at given temperatures, e.g.those associated with Classes A, E and B 4) . The test for ageing in oil, given in previous editions, has been omitted, because it is less severe than the test for ageing in air and gives no indication of the lo
24、ng term effect of oil on various varnished fabrics. 1) BS2757, “Classification of insulating materials for electrical machinery and apparatus on the basis of thermal stability in service”. 2) BS3502, “List of common names and abbreviations for plastics”, gives PTP as the recommended abbreviation for
25、 polyethylene-terephthalate. 3) Terylene is a registered trade name of Imperial Chemical Industries Ltd. 4) As given in BS2757, “Classification of insulating materials for electrical machinery and apparatus on the basis of thermal stability in service”.BS419:1966 BSI 01-2000 iii The long term effect
26、 of varnished fabrics on oil is also of importance and the possibility of including a test for this property is being examined. NOTE 1Where metric equivalents are given the figures in British units should be regarded as the standard. The metric equivalents are approximate. For more accurate conversi
27、on, reference should be made to BS350, “Conversion factors and tables”. NOTE 2In place of the customary but incorrect use of the pound, kilogramme and gramme as units of force, the units called pound-force (abbreviationlbf) kilogramme-force(kgf) and gramme force (gf) have been used in this standard.
28、 These are the forces which, when acting on a body of mass one pound, one kilogramme or one gramme respectively, give it an acceleration equal to that of standard gravity. A British Standard does not purport to include all the necessary provisions of a contract. Users of British Standards are respon
29、sible 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, pagesi toiv, pages1 to19 and a back cover. This standard has been updated (see copyright d
30、ate) and may have had amendments incorporated. This will be indicated in the amendment table on the inside front cover.iv blankBS419:1966 BSI 01-2000 1 1 Scope This BritishStandard covers fabrics woven from cotton, silk, nylon polyethylene-terephthalate (PTP) 5)and glass, coated on both sides with v
31、arnish, and of nominal thickness from4mil(0.10mm) to10mil(0.25mm) supplied in the full width of approximately36inches(915mm) or slit into tape. Although the types of varnished fabric are described throughout this standard as “yellow” and “black”, any varnish having the appropriate properties but dif
32、fering in colour may be used, by agreement between the purchaser and the supplier. 2 Definitions For the purposes of this specification the following definitions apply: tape material cut to a width not exceeding4inches(100mm). It may be either straight-cut or bias-cut and has no selvedges straight-c
33、ut (S/C) material in which one set of threads (usually the warp) is parallel with the edges and the other set at a right-angle bias-cut (B/C) material cut so that both the warp and weft threads make the same angles with the edges panel form bias-cut bias-cut material in short lengths not joined toge
34、ther sewn bias-cut bias-cut material in short lengths sewn together before or after varnishing to form a continuous length stuck bias-cut bias-cut material in short lengths stuck together with an adhesive or an adhesive tape after varnishing to form a continuous length seamless bias-cut bias-cut mat
35、erial woven and varnished in a continuous length roll material in roll form when the width is greater than4inches(100mm) reel material in roll form when the width does not exceed4inches(100mm) 3 Designation For the purposes of this BritishStandard, varnished fabrics are designated by the base fabric
36、 and by the varnish used, as follows: 4 Quality All the material in any one consignment shall be of the same quality and have the same properties, within the limits of this specification, throughout the whole length of each roll or reel. The varnished fabric shall be flexible and the surface shall b
37、e uniform, reasonably smooth and free from defects, such as bubbles, pinholes, creases and flaws. It shall be capable of being unrolled without damage. The material from which tape is cut shall comply with the requirements of this specification. 5 Thickness The thickness, when determined as describe
38、d in Appendix B shall lie within the, appropriate limits given in Table 1. The tolerance on thickness of material of other nominal thicknesses, shall be the subject of agreement between the purchaser and the supplier. 5) See BS3502, “List of common names and abbreviations for plastics”. Type designa
39、tion Material Colour designation C1 C2 S1 S2 N1 N2 P1 P2 G1 G2 Varnished cotton Varnished cotton Varnished silk Varnished silk Varnished nylon Varnished nylon Varnished PTP Varnished PTP Varnished glass Varnished glass Yellow Black Yellow Black Yellow Black Yellow Black Yellow BlackBS419:1966 2 BSI
40、01-2000 Table 1 Thickness 6 Width The following tolerances shall be allowed on the width: a) The width of material nominally36inches(915mm) wide shall be36 1inch(915 25mm). The tolerance on nominal widths less than36inches(915mm) and greater than4inches(100mm) shall be the subject of agreement betwe
41、en the purchaser and the supplier. b) The tolerance on the width of straight-cut or bias-cut tape i.e.,nominal widths up to4inches(100mm) shall be 1 / 64 inch(0.4mm). 7 Length The length of material in a roll or reel should be specified by the purchaser. Recommended lengths are as follows: Rolls: 50
42、,100 and200yards or metres2percent Reels: 36,50 and72yards 2per cent or50 and100metres 2percent. 8 Joins a) Sewn and stuck bias-cut material. The piece length of material between any two successive joins shall be not less than48inches(1.2m). The material shall be in one continuous jointed length unl
43、ess otherwise agreed between the purchaser and the supplier. The joins shall be unmarked and their tensile strength shall comply with the requirements of Table 3 unless otherwise agreed between the purchaser and the supplier. The adhesive or adhesive tape used for stuck joins and the method of makin
44、g the join shall be the subject of agreement between the purchaser and the supplier. b) Straight-cut and seamless-bias-cut material. The recommended roll or reel lengths shall be as far as possible continuous and unjointed. In no case shall there be more than two pieces or one join in rolls or reels
45、 of length up to72yards or50metres or three pieces or two joins in rolls or reels longer than72yards or50metres. No individual piece length or distance between joins shall be shorter than10yards(10m). Any discontinuity in rolls shall be clearly marked. Material Nominal thickness Thickness limits Min
46、imum Maximum Varnished cotton Varnished silk Varnished nylon Varnished PTP Varnished glass mil a5 7 10 4 5 6 5 6 7 5 6 7 10 5 6 7 10 mm 0.13 0.18 0.25 0.10 0.13 0.15 0.13 0.15 0.18 0.13 0.15 0.18 0.25 0.13 0.15 0.18 0.25 mil a5.0 6.3 9.0 3.5 4.5 5.4 4.5 5.4 6.3 4.5 5.4 6.3 9.0 4.5 5.4 6.3 9.0 mm 0.1
47、3 0.16 0.23 0.09 0.11 0.13 0.11 0.13 0.16 0.11 0.13 0.16 0.23 0.11 0.13 0.16 0.23 mil a6.0 7.7 11.0 4.5 5.5 6.6 5.5 6.6 7.7 5.5 6.6 7.7 11.0 5.5 6.6 7.7 11.0 mm 0.15 0.19 0.28 0.11 0.14 0.17 0.14 0.17 0.19 0.14 0.17 0.19 0.28 0.14 0.17 0.19 0.28 a 1mil=0.001in(0.025mm).BS419:1966 BSI 01-2000 3 c) Pa
48、nel form bias-cut material. The recommended roll or reel lengths shall be made up of pieces not less than48inches(1.2m) in length. Individual pieces shall be made up into rolls or reels of appropriate total length by interleaving with a suitable paper. 9 Packaging Material wider than4inches(100m) sh
49、all be rolled on a cardboard or other suitable tube, the length of which shall not be less than the full width of the material. Material4inches(100mm) wide or less shall be reeled on a cardboard or other suitable tube, the length of which shall not exceed the width of the material. The material shall be packed so as to be well protected from dust, dirt and moisture. Each package shall be clearly labelled on the outside with the following information: a) The number of this BritishStandard, BS419 (see Note1). b) The type designation, as giv
