इंटरनेट मानक Disclosure to Promote the Right To Information Whereas the Parliament of India has set out to provide a practical regime of right to information for citizens to secure access to information under the control of public authorities, in order to promote transparency and accountability in the working of every public authority, and whereas the attached publication of the Bureau of Indian Standards is of particular interest to the public, particularly disadvantaged communities and those engaged in the pursuit of education and knowledge, the attached public safety standard is made available to promote the timely dissemination of this information in an accurate manner to the public. “जान1 का अ+धकार, जी1 का अ+धकार” “प0रा1 को छोड न' 5 तरफ” “The Right to Information, The Right to Live” “Step Out From the Old to the New” Mazdoor Kisan Shakti Sangathan Jawaharlal Nehru IS 12753 (1989): Electrogalvanized Coatings on Round Steel Wire [MTD 7: Light Metals and their Alloys] “!ान $ एक न' भारत का +नम-ण” Satyanarayan Gangaram Pitroda “Invent a New India Using Knowledge” “!ान एक ऐसा खजाना > जो कभी च0राया नहB जा सकता ह” है” ह Bhartṛhari—Nītiśatakam “Knowledge is such a treasure which cannot be stolen” -------- IS 12753: lPS9 (Reaffirmed 2001) Indian Standard ELECTROGALVANIZED COATINGS ON ROUND STEEL WIRE - SPECIFICATION ma *3;cmfh UDC YnaS ST?if; faavaw~~*df~f*~ 669’14-426’2 : 669’587 @ BIS 1990 BUREAU MANAK February 1990 OF BHAVAN, INDIAN STANDARDS 9 BAHADUR SHAH NEW DELHI 110002 ZAFAR MARG Price Groq 2 __--. I... --. .--- ‘Metallic and Non-Metallic Finishes Sectional Committee, MTD 20 FOREWORD This Indian Standard was adopted by the Bureau of Indian Standards on 20 July 1989, after the draft finalized by the Metallic and Non-Metallic Finishes Sectional Committee had been approved by the Metallurgical Engineering Division Council. Electrogalvanizing of steel wires is a growing industry; however it is yet to intensify its applications. Electrolytic process has not found wider acceptance in comparison to the zinc coating by hot-dipping process [ covered by IS 4826 : 1979 ‘Hot dipped galvanized coatings on round steel wire (First revision )’ I, because of the initial high capital cost of installation and of skilled personnel. Advantages of electrogalvanizing over the hot dip process are: a) Closer control of coating thickness and, therefore, saving of zinc; b) Electrogalvanized zinc is pure, more concentric and uniform and is more versatile in usef c) No ash or zinc dross is formed; d) Heavier coatings ( up to 1’2 kg/m2 ) is possible only with electrogalvanizing; e) Plant can be shut down quickly and restarted quickly; and f) Electrogalvanized steel wires are better for further drawing and stranding. However, hot dip galvanizing requires less space and gives lustrous zinc coatings, while protection far both types is similar. In order to rationalize the requirements of different galvanized wires, coatings have been grouped into three types, that is, heavy, light and For general guidance, Annex A indicating applicability of various types of coatings on wires has been included.’ corrosion types of medium. different For the purpose of deciding whether a particular requirement of this standard is complied with, the final value, observed or calculated, expressing the results of a test or analysis, shall be rounded off in accordance with IS 2 : 1960 ‘Rules for rounding off numerical values ( revised )‘. The number of significant places retained in the rounded off value should be the same as that of the specified value in this standard. I§ 12733 : 19891 Indian Standard 'ELECTROGALVANIZEDCOATINGSON ROUND STEEL WIRE-SPECIFICATION " 1 SCOPE are in accordance with definitions in IS 3554 : 1966 and IS 1956 ( Part V ) : 1976. 1.1 This standard covers the requirements of electrogalvanized coating on steel wires of circular section in diameters from 0’2 mm up to and including 10 mm and lays down specifications for: 4 SUPPLY OF MATERIAL 4.1 General requirements relating to the supply of material shall conform to IS 1387 : 1967. a) mass of zinc coating, 5 GENERAL REQUIREMENTS ~b) uniformity 5.1 Quality of Zinc For best results, zinc anodes of special high grade ( 99’99 percent pure zinc ) as given in IS 2605 : 1985 are recommended in continuous electrogalvanizing plants. With this, the formation of sludge is minimized while the quality of coatings is better maintained. of zinc coating, and c) adhesion of zinc coating. 1.2 It also lays down methods of testing for these properties and provides for such testing to be carried out before and/or after the wire has been used for armouring, stranding, etc. 1.3 This standard makes no reference to the quality of wire itself. It does not apply to the articles made from wire which have been electrogalvanized after fabrication. 5.2 Sometimes insoluble anodes as well as soluble zinc anodes of lesser purity, along with continuous filtration of electrolytes are also used. 6 MATERIALS 1.4 The relevant Indian Standard governing a particular type of wire should refer to this standard for specifying the requirements of electrogalvanized zinc coating. 2 REFERENCES 2.1 The following Indian Standards are necessary adjuncts to this standard. Title .ZS No. IS 1387 : 1967 General requirements for the supply of metallurgical materials ( Jirst revision ) Glossary of terms relating to IS 1956 ( Part V ) : 1976 iron and steel: Part V Bright steel bar wire ( first revision ) IS 2605 : 1985 Zinc anodes for electroplating ( first revision ) IS 2633 : 1986 Method of testing uniformity of coating of zinc coated articles ( second revision) IS 3554 : 1966 Glossary of terms electroplating relating to IS 6745 : 1972 Methods for determination of mass of zinc coating on zinc coated iron and steel articles 3 TERMINOLOGY .3.1 Definitions of the terms used in this standard AND MANUFACTURE 6.1 The coatings shall be uniform, reasonably smooth and essentially produced by electro-deposition. adherent, pure zinc 6.2 Defects in the surface of steel wire, such as scratches, cracks, pits, inclusions, die marks, etc, may adversely affect the appearance and performance of the electro-deposited zinc coating. The steel wire shall be subjected to such polishing or buffing operations as are necessary to yield deposits with the desired final lustre and appearance. The specifications covering the basic steel wire to be electrogalvanized shall be agreed to between the purchaser and the supplier, according to the applications of the electrogalvanized steel wires. 6.3 Cleaning of Basis Metal Proper preparatory procedures and thorough cleaning and rinsing of the basis steel wire ( dry or wet drawuandlor annealed ) shall be done to ensure satisfactory adhesion and corrosion resistance performance of the coating. 6.4 Electrogalvanizing Electrogalvanizing or electroplating of zinc on steel wires may be from any suitable bath like sulphate, sulphate-chloride, chloride’, fluoroboplants rate, etc. Continuous electrogalvanizing of horizontal line or vertical line are normally designed and the process of electrogalvanizing shall be generally as follows: a)’ Pay-off reels; b) Heat treatment (dipping in molten lead, etc ) if required; ‘” 1 L: L.___...._...~.__ _ 18 12753:1989 4 Pickling in acid; 4 Rinse; 4 Electrol’)tic cleaning; f 1 Rinsingg) Mechan ‘1cal cleaner; other similar purpose, the minimum coating shall be reduced by 5 percent. mass of 7.1.2 Care shalltbedexercised to avoid damaging the samples in detaching them from the finished strand or cable or coil. h) Electra-galvanizing; 3 Cold water rinse; k) Hot water rinse; 4 Supplementary treatment, if desired: i) Chromate passivation ( light coating), ii) Phosphate coating ( light coating); Rinsing and drying; and P> Take-up unit. n> NOTE - The electroplated zinc surface is attacked by supplementary treatments, thereby diminibhirig the coating thickness. It is recommended that extra thickness be built for making up this loss. 7.2 Freedom from Defects The electrogalvanized steel wire shall be uniform, smooth and free from visible plating defects such as blisters, pits, roughness, nodules, cracks, burning or unplated area and shall not be stained, rusted or discoloured. The zinc coating shall be continuous and firmly adherent to the surface of steel. 7 COATING REQUIREMENTS 7.2.1 At allpoints more than 3 cm from a cut end, the coating shall -withstand the number of dips in copper sulphate solution set out in Table 1 and Table 2. when subjected to the Preece test prescribed in IS 2633 : 1986. 7.1 Mass of Zinc Coating 7.2.2 Finish When determined in accordance with IS 6745 : 1972, the mass of zinc coating shall not be less than the mass specified in Table 1. For Z-type coating, the requirements given in Table 2 shall apply. Unless otherwise, stated, the finish shall be bright or semi-bright or dull subject to the agreement between the purchaser and the manufacturer. 7.1.1 If the wire is tested after being used for stranding, armouring, barbing, binding or any Table 1 7.2.3 Even the best electroplating practice cannot remove the defects, for example, scratches, cracks, pits, inclusions, die-marks, etc, on the surface of the basis steel wire. Accordingly, the Mass of Electroplated Coating of Zinc and Number of Dips ( Clauses 7.1 and 7.2.1 ) Light Coated Wire Heavy Coated Wire Nominal r-___-_-__ L-__-) r----Diameter Soft Soft Hard Hard of Electroc-_‘_-_-_~ -h_----, r-_-h--~ r____h___._~ Galvanized c--Number Mass of Number Mass of Number Mass of Mass of Number Wire of Dips Coating of Dips Coating of Dips Coating Coating of Dips r--h? g/m* F-*-Y g/m” ‘;--*T g/m* Above Up to and g/m8 -*-3 r--h--I 1 1 1 Including t t min min min min min min min min (11) (12) (5) (6) (9) (10) (13 1 (14) (7) (8) (f 1 (2) (4) No test No test 15 No test No test 45 No test No test 45 No test No test 0’200 0.315 requirrequirrequirrequirrequirrequir- requiri required ed ed 70 :: z”, 15 Cz do Fl: do 0.400 20 0.315 do ;8 do do do 15 :“o do 0.500 0.400 1% do do 20 100 do do 1 :o” 0,560 0.500 110 :: 20 110 0.63 0560 :: 120 : :: 3’0” :: 120 d”: : do 0.71 0.63 140 140 do 1 0 80 30 0.71 :: 150 dd: 150 do : 30 ddoo 40 0.90 0.80 r 170 0 do 150 : 40 do 1.00 0.90 do 160 : 180 do 40 40 do 1.00 1.25 40 : I 200 do 40 50 I.40 1.25 180 190 : 1 1 :: do 210 :: 50 I .60 60 1’40 1 200 1 230 60 60 1.60 1.80 : : 240 :: z 210 1 i0 2.00 1’80 1 210 240 2.00 2.24 g 70 :o, 230 : 1 260 z 2.50 2’24 2 230 2 1 260 do 70 r 2’80 2’50 1 270 1:: 2.80 3’15 250 240 2’ :: f s’o” 270 110 3.55 3.15 i 260 2 Y280 11 1% : 4.00 120 3’55 2 290 : 1 275 2 1 5’00 4.00 130 2 1 1 110 290 140 7.10 5.00 3 290 300 23 L 300 : 140 10.0 7.10 1 110 z ::2 IS 12753 : 1989 Table 2 Requirements for Medium ( Z-Type ) Electroplated Coatings of Zinc ( Clauses 7.1 and 7.2.1 ) Mass of Coating s/n-P (2) f”l”, 30 0.200 and Up top315 0.400 35 0.315 ,, 0.500 45 0.400 ,, 0.560 60 0’500 ,, 0.63 60 0.560 ,, 0.71 60 0.63 O*SO 75 0’71 :; 0.90 0.80 ,, 7755 1’00 0.90 1, 1.25 90 1’00 .. 1.25 1: 1.40 90 Nominal Diam’eter of Galvanized Wire, Above ,. ,, ,? *, ,V ,’ 9, __ ., __ ,I 1, 1, .~_ . .,*. ,3 1) ,* a. ?- ,, 3, -~ 1’40 ;I;; 2.00 2’24 2’50 2’80 3.15 3.55 4.00 Nomin;jH&neter ---? 1 &in * min (3) - (4) - 9 1 - mm 1Jp to and including 3.55 Over 3.55 upto and including 7.10 Over 7’10 Minimum Complete Turns of Wrap 10 Rutio Between Mandrel Diameter and of Wire 4 10 6 f_ C . one 90” bend ) 6 1 : 1 : : 1 1 bending, the plated coating does not flake off nor crack to such an extent that there is possibility of removing any zinc by rubbing with bare fingers, the use of nail being not allowed. : 1 1 - 8.3 The electrogalvanized coating shall not flake off, when subjected to dry or wet drawing. Ths total reduction should be minimum 20 percent. L; 1 9 SAMPLING - : 9.1 The samples ing plan wire or absence shall be zer and : 1 electroplaters responsibility for defects in the zinc coating, resulting from such conditions shall be waived. 8 ADHESION Requirements for Adhesion Test C C&use 8.1.2) Number of Dips 95 1.60 1.80 2.00 1:; 2.24 105 2.50 110 2.80 120 3’15 120 3.55 135 4.00 135 5.00 150 :: ,. .. :: ;, ,, ,, .. ;; ,, Table 3 size of the batch and the number of to be selected shall be as per the samplspecified in the standard governing the article fabricated from wire. In the of such standard, the degree of sampling as agreed to between the electrogalvanithe purchaser. 9.1.1 Coil for testing shall be selected by the purchaser. 9.1.2 Portions of wires which are obviously damaged shall not be used as samples. OF ZINC COATING 8.1 Test Specimen 8.1.1 The test specimen consists of a piece of wire, long enough to allow the test to be carried out properly. 8.1.2 The test specimen shall be wound round a cylindrical mandrel so as to form close spirals as specified in Table 3. 9.2 Batch For the purpose of this standard a batch shall consists of wires of same dimensions processed together from pretreatment to final electrogalvanizing. 8.2 Proceduie 8.2.1 Winding shall be carried out at a rate not more than 15 turns per minute. 8.2.2 When so wound or bent around the mandrel, the zinc plating shall remain adherent to the steel wire and shall be considered as meeting this requirement if owing to such winding or 10 RETEST 10.1 If the batch sample fails to meet any of the requirements of this standard, double the number of samples, further shall be tested for each failure and if any of the sample fails, the batch shall be treated as rejected. ANNEX A ( Foreword ) GENERAL GUIDANCE Application FOR APPLICABILITY OF TYPE OF COATING DIFFERENT APPLICATIONS Type of Coating r----h-__, Heavy Light Mediuz Fencing wire Stay strand wire Signal strand wire Chain link wire Rope wire Spring wire Cable armouring wire ACSR wire Mild steel wire X X x x x - x - x x X x .X X - x Applicable, -Not applicable. Application Telephone wire Cycle spoke wire Barbing wire ( line ) Barbing wire ( point ) PC. wire Lighting conductor wire Rubber hose reinforcement wire 3 FOR Type of Coating r----h---- Heavy x Light X Mediuz - x x x X - - X x - X - I I Standard Mark I The use of the Standard Mark is governed by the provisions of the Bureau of Indian The Standard Mark on Standards Act, 1986 and the Rules and Regulations made thereunder. products covered by an Indian Standard conveys the assurance that they have been produced to comply with the requirements of that standard under a well defined system of inspection, testing and quality control which is devised and supervised by BIS and operated by the producer. Standard marked products are also continuously checked by BIS for conformity to Details of conditions under which a licence for the use that standard as a further safeguard. of the Standard Mark may be granted to manufacturers or producers may be obtained from the Bureau of Indian Standards. I I ; Bureao of Indian Standards ‘( BIS is a statutory institution established under the Bureau of Indian Standards promote harmonious development of the activities of standardization, marking certification of goods and attending to connected matters in the country. ! Act, 1986 to and quality Copyright BIS has the copyright of all its publications. No part of these any form without the prior permission in writing of BIS. This the course of implementing the standard, of necessary details, grade designations. Enquiries relating to copyright be addressed publications may be reproduced in does not preclude the free use, in such as symbols and sizes, type or to the Director ( Publications ), BIS. Revision of Indian Standards Indian Standards are reviewed periodically and revised, when necessary and amendments, if any, are issued from time to time. Users of Indian Standards should ascertain that they are in possession of the latest amendments or edition. Comments on this Indian Standard may be sent to BIS giving the following reference: Dot : No. MTD 20 ( 3161) Amendments Issued Since Poblicatioo Amend No. BUREAU Headquarters Text Affected Date of Issue OF INDIAN STANDARDS : Manak Bhavan, 9 Bahadur Shah Zafar Marg, New Delhi 110002 Telephones : 3310131, 331 13 75 Telegrams : Manaksanstha ( Common to all Offices ) Telephone Regional Offices : Central NEW DELHI Eastern I : Manak Bhavan, 9 Bahadur Shah Zafar Marg, 110002 : l/14 C. I. T. Scheme VII M, V. I. P. Road, Maniktola CALCUTTA 331 01 13 31 75 37 86 62 700054 Northern : SC0 445-446, Sector 35-C, CHANDIGARH 160036 2 18 43 Southern : C. I. Ts. Campus, IV Cross Road, MADRAS 600113 41 29 16 Western : Manakalaya, E9 MIDC, BOMBAY 400093 Marol, Andheri ( East ) 6 32 92 95 Branches : AHMADABAD. BANGALORE. BHOPAL. BHUBANESHWAR. COIMBATORE. FARIDABAD. GHAZIABAD. GUWAHATI. HYDERABAD. JAIPUR. KANPUR. PATNA. TRIVANDRUM. Printed at Swatantra Bharat Press, Delhi, India