Disclosure to Promote the Right To Information

Transcription

1 इ टरन ट म नक 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. ज न1 क अ+धक र, ज 1 क अ+धक र Mazdoor Kisan Shakti Sangathan The Right to Information, The Right to Live प0र 1 क छ ड न' 5 तरफ Jawaharlal Nehru Step Out From the Old to the New IS (1986): Method of determination of diffusible hydrogen content of deposited weld metal from covered electrodes in welding mild and low alloy steels [MTD 11: Welding General]! न $ एक न' भ रत क +नम-ण Satyanarayan Gangaram Pitroda Invent a New India Using Knowledge! न एक ऐस खज न > ज कभ च0र य नहB ज सकत ह ह Bhartṛhari Nītiśatakam Knowledge is such a treasure which cannot be stolen

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4 1 3 JAN. fw9 IS : (Reaffirmed 1997) Indian Standard METHODS FOR DETERMINATION OF DIFFUSIBLE HYDROGEN CONTENT OF DEPOSITED WELD METAL FROM COVERED ELECTRODES IN WELDING MILD AND LOW ALLOY STEELS ( First Reprint OCTOBER 1998 ) UDC : 543 [ ] 0 Copyright 1987 BUREAU OF INDIAN STANDARDS MANAK BHAVAN, 9 BAHADUR SHAH ZAFAR MARG NEW DELHI Gr 4 May 1987

5 IS : Indian Standard METHODS FOR DETERMINATION OF DIFFUSIBLE HYDROGEN CONTENT OF DEPOSITED WELD METAL FROM COVERED ELECTRODES IN WELDING MILD AND LOW ALLOY STEELS Welding General Sectional Committee, SMDC 14 Choirmon SHRI D. S. HOWAVAR Members Representing D & H Sechcron Electrodes Pvt Ltd, Indore SHRI S. R. JANA ( Alternate to Shri D. S. Honavar ) SHRI R. S. AGGARWAL Association of Indian Engineering Industry, New Delhi SHRI J. K. AHLTJWALIA Stewarts & Lloyds of India Ltd, Calcutta SHRI T. K. BASU ( Alternote ) SHRI H. N. AHUJA Directorate General of Employment and Training, New Delhi DR S. BALASUBRAWNIAN Peico Electronics and Electricals Ltd. Bombay DR S. BHATTACHARYYA ( Alternate ) SHRI K. BALUANOHAR SHR~ R. V. KALE ( AIterncte ) Hindustan Shipyard Ltd, Vishakhapatnam SHRI R. BANERJFE SHRI S. K. DAS (Alternate ) Indian Oxygen itd, Calcutta SHRI S. C. BHAWAL SHRJ K. L. BARUX ( Alternate ) National Test House, Calcutta SHRJ S. K. BUR!.IAN M. N. Dastur & Co Pvt Ltd, Calcutta SHRI B. B. GHOSH ( Alternate ) ( Continued on page 2 ) Q Copyright 1987 BUREAU OF INDIAN STANDARDS This publication is protected under the Indian Copyright Act ( XJY of 1957 ) and reproduction in whole or in part by any means except with written permission of the publisher shall be deemed to be an infringement of copyright under the said Act.

6 IS : ( Continuedfrompage 1 ) Members SHRI R. S. CHOUDWRY DEPUTY DIRECTOR ( CHEMICAL ) RDSO, Lucknow PRODUCTION ENQINE~R INTEGRAL COACH*FACTORY, MADRAS ( Alternate ) SHRI S. C. DEY SHRI C. R. GHOSH SHRI D. B. MOHARIL ( Alternate ) SHRI I. P. KAPOOR SHRI L. M. TOLANI ( Alternate ) Representing Steel Authority of India Ltd (Bokaro Steel Plant ), Bokaro Steel City Ministry of Railways Central Boilers Board, New Delhi Mukand Iron & Steel Works Ltd, Bombay Department of Atomic Energy, Bombay SHRI S. MAJUMDAR Directorate General of Technical Development, New Delhi SHRI S. K. BHATIA ( Alternate ) SHRI R. S. MALLICK Gas Authority of India Ltd, New Delhi SHRI N. MUMMOORTHY Engineer-in-Chief s Branch, Ministry of Defence SHRI H. S. DUGGAL ( Alternate ) SHRI J. D. PANDA Dalmia Institute of Scientific & Industrial Research, Rajgangpur SHRI RAJISDRA NATH I Alternate I 1 SHRI S. L. V. RANGAN ( Alternate li 1 SHRI K. M. POLE SHRI G. D. APTE ( Alternate ) %&handnagar Industries, Walchandnagar DR S. PRASANNA KUUAR Larsen & Toubro Ltd, Bombay SHRI J. K. NANDA ( Alternate ) SHRI J. R. PRASHER SHRI N. RADHA KRISHNAN SHRI B. RAMASWAMY SHRI S. M. KADAM ( Alternote ) DR V. RAMA~WAMY Engineers India Ltd, New Delhi Binny Ltd. Madras Indian Hume Pipes Co Ltd, Pune Steel Authority of India Ltd ( Research and ;rnl;ipment Centre for iron and Steel), DR S. K. CH~UDHURY ( Alternate ) SHRI P. H. MADHAVA REDDY Bharat Heavy Plate and Vessels Ltd, Vishakhapatnam SHRI M. G. NARAYANA RAO ( Alternate ) REPRESENTAIIVE Bharat Heavy Electricals Ltd, Hyderabad SHRI RAMESH KUMAR ( Alternate I ) SHRI V. SREEMANNARAYANA ( Alternate II ) REPRESENTATIVE Jessop & Co Ltd. Calcutta SHRI N. K. ROY Projects & Development India Ltd, Dhanbad SHRI P. K. ROY ( Alternate ) SHRI S. K. ROY Mini&y of Defence ( DGI ) SHRI B. K. SINQH Tata Engineering and Locomotive Co Ltd. Jamstiedpur SHRI A. V. MULEY ( Alternate I ) SH~U P. S. JOSHI ( Afternate II ) SHRI V. K. SRIDHAR Directorate General New Delhi SHRI R. C. SHARMA ( Alternate ) 2 of Supplies and Disposals, ( Continued on page 13 )

7 IS: Indian Standard METHODS FOR DETERMINATION OF DIFFUSIBLE-HYDROGEN CONTENT OF DEPOSITED WELD METAL FROM COVERED ELECTRODES IN WELDING MILD AND LOW ALLOY STEELS 0. FOREWORD 0.1 This Indian Standard was adopted by the Indian Standards Institution on 14 August 1986, after the draft finalized by the Welding General Sectional Committee had been approved by the Structural and Metals Division Council. 0.2 This standard covers the methods for determination of diffusible hydrogen of deposited weld metal by mercury and glycerin method. The correlation of mercury and glycerin methods is given in Appendix A for information. 0.3 In the preparation of this standard, assistance has been derived from the following publications: IS Welding - Determination of hydrogen in deposited weld metal arising from the use of covered electrodes for welding mild and low alloy steels. International Organization for Standardization. BS 639 : 1976 Covered electrodes for the manual metal arc welding of carbon and carbon manganese steels. British Standards Institution. JIS : Z Method for measurement of hydrogen evolved from deposited metal. Japanese Standards Association. Rules and regulations for classification of ships Lloyd s Register of Shipping, United Kingdom. 1. SCOPE 1.1 This standard covers the procedures for determination of content of diffusible hydrogen in deposited weld metal arising from the use of shielded 3

8 IS: metal arc electrodes for welding mild and low alloy steels by mercury and glycerin methods. For glycerin method, the values reported shall be in terms of evaluation by mercury method using the formula given in Appendix A. The glycerin method shall be used as a routine method. The mercury method shall be used as a referee method in case of disputes, in addition to being used as a routine method. 2. TERMINOLOGi 2.1 For the purpose of this standard, the definitions given in IS : * shall apply. 3. PRINCIPLES OF MEASUREMENT 3.1 Mercury Method - The diffusible hydrogen content of the weld metal sample is made to collect over mercury at room temperature for sufficient time. The amount of hydrogen thus released is measured by volumetric methods. 3.2 Glycerin Method - The diffusible hydrogen content is made to collect over glycerin in a bath maintained at 45 C for sufficient time. The amount of hydrogen thus evolved is measured volumetrically. 4. MATERIALS REQUIRED FOR TEST 4.1 Parent Plate Material - The test assembly shall be prepared from steel conforming to IS : or IS : ~ or IS : s or equivalent material. 4.2 Electrodes - The electrodes to be tested shall be of 4.0 mm core wire diameter, or of 3.15 mm diameter in case of iron powder electrodes having more than 130% metal recovery The electrodes shall be dried before testing as per recommendations of the manufacturer. If no recommendation ii provided by the manufacturer, the electrodes shall be dried as per the schedule given below: 4 Hydrogen controlled electrodes C for two hours or 350 C for one hour. b) Other than hydrogen controned electrodes C for 2 hours, excepting cellulosic electrodes. 4 Ceilulosic electrodes - no drying. *Glossary of terms relating to welding and cutting of metals (first revision ). tspecification for structural steel ( standard quality ) (flfrh revision ). $Specification for steel plates for pressure vessels for intermadiate and low temperature service including boilers (firsr revision). $Qxcification for weldable structural steel ( fhird revision ). 4

9 5. MERCURY METHOD IS: Apparatus - An audiometer type gas burette shown in Fig. 1 may be used for the test. Burettes of other design my be employed provided that the following criteria are fulfilled: a) Mercury is used as the confining fluid. 0 TO 10 ml BURETTE GRADUATED TO 0.05 ml ABOUT 30 mm LENGTH PER ml.or 10 TO a 6 7 / SPHERICAL JOfNT HIGH VACUUM HOLLOW KEY SINGLE OBLIQUE STOP-COCK +4 BORE VACUUM HIGH VACUUM HOLLOW KEY DOUBLE OBLIQUE STOPCOCK *L BORE CONICAL JOlNf 120 STRAIGHT - - SECTION --I _A+- MERCURY BOROSILICATE THROUGHWT GLASS All dimensions in millimetres. FIG. 1 DIFFUSABLE HYDROGEN METER

10 IS : b) It is possible to maintain sample under vacuum for a brief period as specified in (d) to remove entrapped gases in the fractured surface before the sample is subjected to vacuum in the measuring burette. In burettes consisting of single limb, this may be achieved through manipulation of mercury level and the stopcock: any gas released during the brief period of surface degassing being swept out of the burette before the measurements. c) The value of collected gas is measured to an accuracy of at least 0.05 ml under normal temperature and pressure. 5.2 Welding Jig - A copper jig shown in Fig. 2 shall be used in preparing the specimens. SECTION AA FIG. 2 All dimensions in millimetres. TEST PIECE ASSEMBLY FOR HYDROGEN SAMPLING OF WELD DEPOSIT 6

11 IS: Preparation of Test Specimens 53.1 Triplicate sets of test pieces conforming to 4.1 and having a cross section of 10 x 15 mm and length of 30 mm shall be used for each type of electrode being tested. The test pieces shall be degassed at 650 C for one hour and then kept in a desiccator in dry condition prior to use The test piece a ssembly shown in Fig. 3 consists of run-on and run-off pieces and a central sample section of 30 mm length. The 30 mm centre portion shall have a length tolerance of & O-25 mm and shall be weighed nearest to. IO mg before testing. All dimensions in millimctres. FIG. 3 SPECIMEN ASSEMBLY Welding - The temperature of the ji, 0 shall be 30.-t 10 C before testing. The welding current shall be 15 amperes less than the maximum recommended by the manufacturer, the Fachine setting being controlled to within -& 5 amperes. The speed of welding shall be adjusted to an electrode consumption between 12 and 13 mm per IO mm of bead length. The time spent on the deposition shall be noted A bead of 100 mm length shall be deposited along the centre-line of each test assembly. No burning off of the tip of the electrode prior to testing is allowed Three seconds after extinction of the arc, the jig shall be released and the test piece assembly shall be quenched in iced water and subsequently in alcohol or acetone saturated with carbon dioxide at a temperature of - 50 C or below. The sample pieces shall be broken apart while cold, using brief intermittent periods of cooling; the intervals spent outside the cooling bath in these operations shall not exceed IO seconds each. The samples may now be stored at or below -WC for a period upfo 3 days before analysis. 7

12 IS : Test Procedure Preparation of Sample for Analysis -When transferring the sample to gas burette, a shield of dry nitrogen shall be applied to avoid condensation of atmospheric humidity. The sequence of operation and the time spent in each shall be as follows: The sample shall be washed in alcohol for a period of 3 to 5 seconds. The sample shall be washed in pure ether for a period 5 seconds. between 3 to ( The sample shall be dried in a blast of dry nitrogen supplied from a nozzle, particular attention being paid to the fractured surface of the specimen. The operation shall be accomplished in not less than 20 seconds and not more than 22 seconds. While maintaining a blanket of dry nitrogen, the sample shall be transferred to the outer limb of the burette (audiometer) where the sample shall be held in position clear of the mercury surface by a magnet. The outer limb of the burette shall then be evacuated down to a pressure of approx 13Pa ( 0.1 mm Hg). The time spent in these operations shall be not less than, 20 seconds and not more than 25 seconds. The sample shall then be transferred through mercury air Ioek fo its final position in the measuring limb of the burette. This operation shall be accomplished within 5 seconds. The total time spent in transferring the sample until meaqurements commence shall not exceed 60 seconds Analytical Procedure - The sample shall be maintained under reduced pressure at 25 & 10 C for a period of 72 hours when the final volume shall be measured. The barometric pressure as well as the precise temperature shall be recorded. The sample shall be removed from the apparatus and thoroughly brushed to remove any oxide skin and then weighed to an accuracy of 10 mg. 5.5 Calcniation and Expression of Results - The volume VI, of diffusible hydrogen per 100 g of deposited metal shall be calculated from the following formula: where vh = v, (B - W (273 + TR) (Mz - M,) VI, = volume of diffusible hydrogen in ml per 100 g of deposited metal at NTP ( 0 C and 760 mm Hg ), 8

13 I, = volume of gas in burette in ml after 72 11, B = barometric pressure in mm Hg, TR = room temperature in C when Vs is measured, H =Z head of mercury in mm at which I :: is measured, IS : MZ z= mass of sample in g after removal from apparatus, and M1 = mass of sample in g before deposition of weld. For the purpose of this standard, the average value of results from three determinations shall be used. 6. GLYCERIN METHOD 6.1 Apparatus - A typical apparatus using glycerin as confining fluid is shown in Fig. 4. The set up consists of the following: a) A thermostatically controlled water bath with circulation and heating arrangements to maintain bath temperature at 45 i 1 C, b) Perforated stand made of metal which will allow free circulation of bath fluid around the glycerine container, and c) Glycerine container and measuring burette wilh inverted chamber which conhnes the sample in a bath of glycerin. The burette is graduated to an accuracy of 0.02 ml. 6.2 Preparation of Test Specimens Test specimen measuring 12 x 25 mm in cross section and approximately 125 mm in length conforming to plate material given in 4.1 shall be used. The specimens shall be free from rust. For each test, four specimens shall be prepared and weighed to 0.1 g accuracy Welding The size of electrodes used for Jeposition of weld bead and the drying of electrodes shall be in accordance with The welding is carried out with a short arc. The welding current shall be 15 amperes less than the maximum specified by the manufacturer. No burn-off of the tip is allowed before the test On the 25 mm surface of each test specimen prepared as per 6.2.1, a single bead of weld measuring approximately 100 mm in length shall be deposited. 9

14 IS: All dimensions in millimetres. FIG. 4 APPARATUS FOR HYDROGEN DETERMINATION BY GLYCERIN DISPLACEMENT METHOD 6.3 Test Procedure - Within 30 seconds of deposition of the bead, the slag shall be removed and the sample quenched in iced water having a temperature not exceeding 5 C for a p,eriod of 30 seconds. Within 10 seconds thereafter, the sample shall be cleaned and then placed in the glycerin bath for collection of hydrogen by displacement of glycerin. The total time spent from the completion of the welding till the transfer of the sample to the glycerin bath shall not exceed 70 seconds. The glycerin bath shall be maintained at 45 f 1 C during the test. All the four specimens shall be welded and placed in the glycerin bath within 30 minutes. 10

15 IS : Hydrogen Measurenzent - The sample shall be kept immersed in glycerin for a period of 48 hours. They shall then be removed from the apparatus and cleaned with water followed by methanol/acetone and weighed to nearest 0.1 g to determine the amount of weld metal deposited. The amount of gas evolved is measured to the nearest 0.05 ml and corrected to 20 C and 760 mm of Hg. 6.4 Calculation and Exprekion of Test Results - The volume VI, of diffusible hydrogen per 100 g of deposited metal shall be calcualted from the following formula: where B vh = VP x -7T (274 + T,:) (M2@;) vh = volume of diffusible hydrogen in ml per metal at NTP ( 0 C and 760 mm Hg ), V, - volume of gas evolved in burette in ml after4s 11, B = barometric pressure in mm Hg, TK = room temperature in C when V, is measured, 100 g of deposited M2 = mass of sample in g after removal from apparatus, and M, = mass of sample in g before deposition of weld. APPENDIX A ( Clauses 0.2 and 1.l ) CORRELATJON OF MERCURY AND GLYCERIN METHODS A-l. As glycerin absorbs some amount of hydrogen evolved by the sample, the results obtained by using this method tend to be somewhat lower. The method is nonetheless is easy to operate and does not involve hazardous chemicals such as mercury, which is a known toxic material and needs careful handling. The glycerin method therefore lends easily to quality control and routine inspection. 11

16 1s: A.;l.teNowing correlation between glycerin and mercury methods may V hc? = 0.64 Vm where VW A hydrogk measured by glycerin method in ml per 100 g of deposited weld metal, and VIM = hydrogen measured by mercury method in ml per 100 g of deposited weld metal. 12

17 Is: ( Continued from page 2 ) Members Representing SHRI H. K. TAF: Indian Register of Shipping, Calcutta SHRI S. CHAN~RA ( Ahernute ) SHRI J R. UPADHY~Y Apar Pvt Ltd. Bombay SWRI B. S. PATEL ( Alternote ) SHIU P. S. VI~VANATH Advani-Oerlikon Ltd. Bombay SHR~ N. VIVANATHAN National Hydroelectric Power Corporation Ltd, New Delhi SHR~ K. RAOHAV~NDRAN, Director General, BIS ( Ex-officio Member ) Director ( Strut & Met ) Secretary SHRI S. S. SETHI Joint Director ( Strut & Metals ), BLS Convener SHRI D. S. HONAVAR Subcommittee for Welding Consumables, SMDC 14 : 1 D & H!&heron Electrodes Pvt Ltd, Indore Members SHRI S. R. JANA ( Alternate to Shri D. S. Honavar ) SHRI R. S. AOOARWAL Modi Arc Electrodes Co, Modinagar SHRI A. V. DESHPANDE ( Alternate ) SHRI AWTAR SINOH Irrigation Works, Chandigarh SHR~ S. K. BASU Indian Oxygen Ltd. Calcutta Sxar R. BANERJEB ( Alternate ) DR S. BHATACHARYYA Peico Electronics and Electricals Ltd, Bombay DR S. BALASUBIUMANIAN ( Alternate ) C~errrsr AND METAL~u~OIST-II Ministry of Railways RDSO, LLJCKNOW ASSISTANT RESEARCH OFFICER RDSO, LUCKNOW ( Alternate ) SHR~ V. H. HA~LANI Ministry of Defence ( DGI ) SHRI K. S. SOUNDAPPAN ( Alternate ) SARI R. M. JAIN Special Machines, Karnal SHRI A. K. GUPTA ( Alternute ) SHIU S. KRISHNAMURTHY ACC Babcock Ltd. Durgapur SHRI PREM KRISHNA ( Alternute) SXIU M. NAGESHWARA RAO Mirhra Dhatu Nigam Ltd. Hyderabad SARI VIWK S. MAYADEo ( Alternate ) SHRI K. NA~ASIMHAN Bharat Heavy Electricals Ltd. Hyderabad SHRI RAMESH KUMAR ( Alternate I ) Smu V. SREEMANNARAYANA ( Alternate II ) 13 ( Continued on page 12 t

18 IS: wdlers Representing StmI ANIL PANDYA SteelB;;;hc$ty of India Ltd ( Bokaro Steel Plant ), SHRI J. R. PRASHER Engineers India Ltd, New Delhi SHRI M. R. C. NAGZRZJ.\N ( Alrernate) ~~_PXI.SENTATIVf., Bharat Heavy Plate and Vessels Ltd, Vishakha- IZ~PRJ~ESTAIIW PowgaEz$cts Division, BARC, Bombay RF PRESESATIVE Dalmia Institute of Scientific and Industrial Research, Rajgangpur SIIRI J. R. UPAOHYAY Apar Pvt Ltd. Vadodara SCiRl P. S.VIsV4NATII Advani-Oerlikon Ltd, Bombay SHKI M. P. DHA~UKA ( Alternate ) 14

19 BUREAU OF INDIAN STANDARDS Headquarters: Manak Bhavan, 9 Bahadur Shah Zafar Marg, NEW DELHI Telephones: , , Fax : , , Telegrams : Manaksanstha * (Common to all Offices) Central Laboratory : Telephone Plot No. 20/Q, Site IV, Sahibabad Industrial Area, Sahibabad Regional Offices: Central : Manak Bhavan, 9 Bahadur Shah Zafar Marg, NEW DELHI *Eastern : 1 /14 CIT Scheme VII M, V.I.P. Road, Maniktola, CALCUTTA Northern : SC , Sector 34-A, CHANDIGARH Southern : C.I.T. Campus, IV Cross Road, CHENNAI fwestern : Manakalaya, ES, Behind Marol Telephone Exchange, Andheri (East), MUMBAI Branch Offices:: Pushpak, Nurmohamed Shaikh Marg, Khanpur, AHMEDABAD $Peenya Industrial Area, 1 st Stage, Bangalore-Tumkur Road, BANGALORE Gangotri Complex, 5th Floor, Bhadbhada Road, T.T. Nagar, BHOPAL Plot No , Unit VI, Ganga Nagar, BHUBANESHWAR Kalaikathir Buildings, 670 Avinashi Road, COIMBATORE t Plot No. 43, Sector 16 A, Mathura Road, FARIDABAD Savitri Complex, 116 G.T. Road, GHAZIABAD Ward No.29, R.G. Barua Road, 5th By-lane, GUWAHATI a-56(3, L.N. Gupta Marg, Nampally Station Road, HYDERABAD E-52, Chitaranjan Marg, C- Scheme, JAIPIJR /418 B, Sarvodaya Nagar, KANPUR Seth Bhawan, 2nd Floor, Behind Leela Cinema, Naval Kishore Road, LUCKNOW NIT Building, Second Floor, Gokulpat Market, NAGPUR Patliputra industrial Estate, PATNA Institution of Engineers (India) Building 1332 Shivaji Nagar, PUNE T.C. No. 14/l 421, University P. 0. Palayam, THIRUVANANTHAPURAM *Sales Cffice is at 5 Chowringhee Approach, P.O. Princep Street, CALCUTTA tsales Cffice is at Novelty Chambers, Grant Road, MUMBAI *Sales Cffice is at F Block, Unity Building, Narashimaraja Square, BANGALORE Reprography Unit, BIS, New Delhi, India