SPECIFICATIONS FOR WELD CONSUMABLES FOR MANUAL …

NCD 1501 ISSUE-1 SEP 2010

SPECIFICATIONS FOR WELD CONSUMABLES FOR MANUAL METAL ARC WELDING (MMAW) OF DMR249A GRADE

STEEL FOR INDIAN NAVAL SHIPS

(Valid up to Aug 2015)

Issuing Authority

Integrated Headquarters,

Ministry of Defence (Navy)

Directorate of Naval Architecture

D-II Wing, Sena Bhawan

New Delhi-110 011

NCD SPECIFICATION

Directorate of Naval Architecture NCD 1501, Issue 1 Page

Integrated Headquarters Ministry of Defence (Navy)

New Delhi-110 011

Specifications for Weld Consumables for Manual Metal Arc Welding of DMR249A

Grade Steel for Indian Naval Ships

Rev. No. 0

Date Sep 10

Specifications for Weld Consumables for Manual Metal Arc Welding (MMAW) of DMR249A Grade Steel for Indian Naval Ships

2 of 35

RECORD OF AMENDMENTS

S.No. Amendment Authority Date Signature

1.

2.

3.

4.

5.

6.

7.

8.

9.

10.



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NCD SPECIFICATION

NCD 1501 ISSUE 1 SEP 2010

SPECIFICATIONS FOR WELD CONSUMABLES FOR MANUAL METAL ARC WELDING (MMAW) OF DMR249A

GRADE STEEL FOR INDIAN NAVAL SHIPS



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CONDITIONS OF RELEASE

1. This NCD specification has been prepared for the use of the Indian Navy and

of its contractors in the execution of contracts for the Indian Navy. 2. This document is Indian Navy copyright and the information therein may be

subjected to Indian Navy rights. It is not to be released, reproduced or published without written permission of the Integrated Headquarters, Ministry of

Defence(Navy). 3. Indian Navy reserves the right to amend or modify the contents of this

specification without consulting or informing any holder of the specification.

4. This specification may call for the use of processes, substances and procedures that may be injurious to health if adequate precautions are not taken. It refers only to technical suitability and in no way absolves either the supplier or

the user from statutory obligations relating to health and safety at any stage of manufacture or use.

5. Where attention is drawn to hazards, those quoted may not necessarily be exhaustive.

6. This specification is the property of the Indian Navy and, unless otherwise authorized in writing by the Integrated Headquarters, Ministry of Defence(Navy),

must be returned on completion of the contract or submission of the tender, in connection with which it is issued.

7. Enquiries in connection to this NCD specification maybe made from Directorate of Naval Architecture, Integrated Headquarters, Ministry of

Defence(Navy), Sena Bhavan, New Delhi, Tele No. 011-23011580/23010942, Fax No. 011-23010126.

8. Unless otherwise specified, reference in this specification to any document means the issue and all amendments to the document current at the date of

issue or subsequent amendments to this specification.



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CONTENTS

S.No. Subject Page no

1. Issuing Authority 1

2. Record of Amendments 2

3. Authorisation 3

4. Conditions of Release 4

5. Contents 5

6. Introduction 6

7. Commonly Used Symbols and Abbreviations 7

8. Related Documents 8

9. Scope 9

10. DCAN Nos. 9

11. Supply of Materials 9

12. Mechanical Properties 10

13. Classification of Weld consumables 10

14. Dimensions and Tolerances 11

15. Testing Requirements 11

16. Initial Tests 11

17. Periodic Check Tests 11

18. Quality Control Tests 12

19. Quality Assurance 12

20. Inspection Authority 12

21. Packing 12

22. Identification and Marking 13

23. Approval for Manufacture 13

24. Approved Sources 13

25. Deviations 13

Appendices/Annexure

A Dimensions and Tolerances 14

B Initial Tests 16

C Test sample for periodic check tests 27

D Quality Control tests 28

E Approved Sources 32

Annexure Welding Procedure Specification 34

Notes 35



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INTRODUCTION

1. This NCD Specification is sponsored by the Indian Navy, Integrated

Headquarters, Ministry of Defence (Navy), Principal Director, Directorate of Naval Architecture, Sena Bhavan, New Delhi-110 011.

2. It is to be applied as required by any Ministry of Defence (Navy) contract for supply of Weld Consumables for Manual Metal Arc Welding of DMR249A Grade

Steel for Indian Naval Ships.

3. If it is found to be technically unsuitable for any particular requirement the sponsor is to be informed in writing of the circumstances with a copy to Principal Director, Directorate of Naval Architecture, Integrated Headquarters, Ministry of

Defence (Navy), Sena Bhavan, New Delhi-110 011. 4. Any user to this Specification may propose an amendment to it which are:-

(a) Not directly applicable to a particular contract are to be made to the

sponsor of the NCD. (b) Directly applicable to a particular contract are to be dealt with using

existing procedures or as specified in the contract.

5. No alteration is to be made to this NCD specification except by the issue of formal amendment.

6. Unless otherwise stated, reference in this NCD specification to approval, approved, authorised or similar terms are by the Integrated Headquarters, Ministry of Defence (Navy).

7. The Naval specifications have been formulated from NMRL, Ambernath

specification no. NMRL/MMat/MMAW-NCM221/R1-2006 as the weld consumables have been developed through NMRL.

8. This specification is valid for a period of 05 years from the date of issue or as and when amended.



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COMMONLY USED SYMBOLS AND ABBREVIATIONS

A Ampere H henry nm nanometer

ac Alternating current h hour No. number

AM amplitude modulation hf high frequency o.d. outside diameter

cd Candela Hz hertz (c/s) W ohm cm Centimeter i.d. inside diameter p. page

CP chemically pure In. inch Pa pascal

c/s cycle per second ir infrared pe probable error

d day J joule pp. pages

dB decibel L lambert ppm part per million

dc direct current l liter qt quart °C degree Celsius lb pound rad radian

°F degree Fahrenheit lbf pound-force rf radio frequency

dia diameter lbf·in pound-force inch rh relative humidity

emf electromotive force lm lumen s second

eq equation ln logarithm (natural) SD standard deviation F farad log logarithm (common) sec. section

fc footcandle M molar SWR standing wave radio

fig. figure m meter uhf ultrahigh frequency

FM frequency modulation min minute uv ultraviolet

ft foot mm millimeter V volt

ft/s foot per second mph mile per hour vhf very high frequency g acceleration m/s meter per second W Watt

g gram N newton λ wavelength

gr grain N m newton meter wt weight

area =unit2 (e.g. ft2, in2, etc.) Volume = unit3 (e.g. ft3, m3, etc.)

Prefixes

d deci (10-1) h hecto (102)

c centi (10-2) k kilo (103)

m milli (10-3) M mega (106)

m micro (10-6) G giga (109) n nano (10-9) T tera (1012)

p pico (10-12)

Common Conversions (See ASTM E380)

m/s ft/s x 0.03048000 kg lb x 0.4535924 m ft x 0.3048 N lbf x 4.448222

J ft·lbf x 1.355818 N/m lbf/ft x 14.59390

g gr x 0.06479891 N·m lbf·in x 0.1129848

cm in x 2.54 Pa lbf/in2 x 6894.757

J kWh x 3,6000,000 km/h mph x 1.609344

L qt x 0.9463529

Temperature T°C (T°F-32) x 5/9

T°F (T°C x 9/5)+32



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RELATED DOCUMENTS

S.No. Document # Document Description

1. IS 812:1957 Glossary of terms relating to welding and cutting of metals.

2. IS 1182:1983 Recommended practice for radiographic examination of

fusion welded butt joints in steel plates (second revision).

3. IS 1387:1993 General requirements for the supply of metallurgical materials (second revision).

4. IS 814: 2004 Covered electrodes for manual metal Arc welding of carbon and carbon Manganese steel-specification.

5. IS 1395:1982 Low and medium alloy steel covered electrodes for manual metal arc welding (third revision).

6. IS 1599:1985 Method for bend test (second revision).

7. IS 1608:1995 Mechanical testing of metals-Tensile testing (second revision)

8. IS 1757:1988 Method for charpy impact test (V-notch) for metallic materials (second revision).

9. IS 11802:1986 Method for determination of diffusible hydrogen content of deposited weld metal from covered electrodes in welding mild and low alloy steels.

10. IS 13851:1993

Storage and re-drying of covered electrodes before use- Recommendations.

11. IS 3600 Part 2:1997 Method of testing fusion welded joints and weld metal in steel-Beam Impact Charpy V notch test.

12. IS 3600 Part 3:1995 Method of testing fusion welded joints and weld metal in steel-Transverse tensile test on butt welds.

13. IS 3600 Part 4:1995

Method of testing fusion welded joints and weld metal in steel-Longitudinal tensile test on cylindrical all weld metal test pieces using butt welds.

14. IS 3600 Part 5:1995 Method of testing fusion welded joints and weld metal in steel-Transverse root and face bend test on butt welds

15. DMRL/NASD/DMR-249A(AR)/2004

Specification for DMR249A steel

16. NMRL/MMat/ MMAW-NCM221/ R1-2006

Specifications for Covered Electrodes for Manual Metal Arc Welding of DMR249A Steel

17. NCM-221-249A-M NMRL Welding procedure specification for MMAW welding of DMR249A steel

Note. The above standards contain provisions, which through reference in this text constitute provision of this standard. At the time of publication, the editions indicated were valid. All standards are subject to revision and parties to agreements based on these standards are encouraged to investigate the possibility of applying the most recent editions of the above standards.



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NCD 1501, Issue 1, Sep 2010

SPECIFICATIONS FOR WELD CONSUMABLES FOR MANUAL METAL ARC WELDING (MMAW) OF DMR249A GRADE STEEL FOR INDIAN NAVAL SHIPS

Scope 1. This specification relates to standard specifications and technical delivery

conditions for indigenously developed DMR249A grade steel weld consumables for Manual Metal Arc Welding (MMAW) to be used for construction and structural

repair purposes onboard warships of Indian Navy. Basic coated, all position, AC/DC, hydrogen controlled, covered electrodes for manual metal arc welding are prescribed by this specification.

2. This specification also prescribes the mechanical properties of the weld deposits.

DCAN Nos.

3. Defence Category Allotment Numbers (DCAN No.) of weld consumables

covered by this specification are as given in Table 1.

Table 1. Pattern nos. of weld consumables

Thickness (in mm) Pattern No.

2.50 N3439-P003731

3.15 N3439-P009732

4.00 N3439-P009739

5.00 N3439-P009733

Supply of Materials

4. General requirements relating to the supply of covered electrodes for manual metal arc welding shall be as laid down in IS:1387:1993.

5. As a guideline, DMR249A grade steel weld consumables as per this

specification are to be procured on competitive basis from approved sources.



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Mechanical Properties

6. The mechanical properties of all weld metal specimen from butt weld, like yield stress, ultimate tensile strength, percentage elongation, charpy impact

strength and diffusible hydrogen content, of MMAW weld consumables shall comply with the values given in Table 2.

Table 2. Mechanical properties

Mechanical Property Value

Yield Stress (MPa) ≥ 500

Ultimate Tensile Strength (MPa) ≥ 600

% Elongation on Gauge Length 5.65 √Sₒ

≥ 22

Impact Toughness at -50 ºC (J) ≥ 50

Diffusible Hydrogen Content, Hdm

(ml/ 100gm of deposited metal)

≤ 4

where Sₒ is gauge area in mm²

Classification of Weld Consumable 7. Type of covering. The covering of the electrodes shall be basic type. 8. Welding position. The electrodes shall be capable of being used in all position

welding and this shall be indicated by the manufacturer on the package.

9. Welding current and voltage. The welding current and open circuit voltage conditions on which the electrodes can be operated as recommended by the manufacturer shall be indicated by appropriate designation. The electrodes shall

be capable of being used with DC± and AC with minimum open circuit voltage of 70V.

10. Hydrogen controlled electrodes. The diffusible hydrogen content of the electrodes in ml/100g of deposited metal as determined in accordance with IS

11802 shall be less than 4 ml/100g. Mercury method shall only be used for this determination.

11. Radiographic Quality electrodes. The electrodes shall be capable of depositing radiographic quality welds.



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Dimensions and Tolerances

12. The dimensions and tolerance of weld consumables shall be as per Appendix A.

Testing Requirements

13. Covered electrodes shall be subjected to the following tests for assessing the mechanical properties of the deposited weld metal and the usability of an electrode for a particular welding position:-

(a) Initial certification tests

(b) Periodic tests

(c) Quality control tests.

14. The parent metal used for test plates shall be DMR249A steel.

Initial Tests

15. Initial tests are certifying or proving tests for each type or modified type of covered electrode. The details of these tests are given in Appendix B.

Periodic Check Tests

16. The periodic check tests comprise of the following tests selected from the initial tests, and are meant to be repeated at intervals to provide evidence that the

electrodes currently produced, possess the properties proved in the initial tests:-

(a) One longitudinal all weld metal tensile test from a butt welded plate

(b) Three all weld metal charpy impact tests from a butt welded plate

(c) Diffusible hydrogen estimation test

17. The periodic check tests shall be conducted at least once in a year. These tests shall also be conducted when the production of the covered electrodes is

resumed after stoppage for more than six months.



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18. The testing shall be carried out for flat down hand welding position. For tests

at Para 16(a) and 16(b), the test sample (as shown in Appendix C) shall be taken from single test assembly welded at vertical up (3G) position. Welding procedure

details for preparation of weld assembly shall be as per Annexure to Appendix B.

Quality Control Tests

19. The details of quality control tests which include following tests shall be as per Appendix D:-

(a) All Weld Metal Mechanical Tests (b) Weld Metal Assembly

(c) All weld Tensile Test (d) All Weld Impact Test (e) All weld chemical composition

(f) Diffusible Hydrogen Evaluation Test

Quality Assurance

20. The quality assurance standards to be achieved for acceptance of weld consumables shall be based on specified requirements/limits with respect to the quality control tests as per Para 19 above.

Inspection Authority 21. Directorate of Quality Assurance (Naval) (DQAN), New Delhi is the inspection

authority for inspection and clearance of DMR249A grade steel weld consumables as per this specification during procurement by Material Organisations and

shipyards. 22. The inspection shall be undertaken in accordance with approved Quality

Assurance Plan. Record of periodic check tests shall be made available and submitted to DQAN by manufacturer during inspection.

Packing

23. Solid bare electrodes shall be suitably packed to guard against damage, combination or deterioration during storage, transit and inspection.



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Identification and Marking

24. The following information shall be clearly marked on each package of solid bare electrodes for easy identification and shall be stamped by DQAN, the clearing

agency:-

(a) Certification coding

(b) Name of manufacturer

(c) Trade designation

(d) Size

(e) Cast number

Approval for Manufacture

25. Weld consumables manufacturers, desirous of producing weld consumables under this specification for Indian Navy, shall approach IHQ, MoD(N) with details

of proposed products. The approval will be considered based on assessment of manufacturing capabilities and suitability of proposed product during testing

process to ensure quality production of weld consumables.

Approved Sources

26. Four sources have been approved by IHQ, MoD(N) to manufacture weld consumables in accordance with this specification and supply to procurement agencies of Indian Navy and Shipyards for use onboard Indian Navy ships. The

contact details of approved manufacturers and their products are given in Appendix E.

Deviations

27. Any major deviation from the requirement specified in above paragraphs above, which affect the performance of the weld consumables, shall be referred to

IHQ, MoD(N) for clarification.

* * * * *



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Appendix A (Refers to Para 12)

DIMENSIONS AND TOLERANCES

Size and Length

1. The size of an electrode shall be designated by the nominal diameter of the core wire expressed in mm. Sizes of electrode and corresponding lengths of

electrodes shall be as given in Table A1.

2. The tolerance on the specified diameter of core wire shall be ±0.05 mm. The tolerance on the specified length of electrode shall be ±3 mm.

Table A1. Sizes and Lengths of Electrode

Size (in mm) Length (in mm)

3.15 350 or 450

4.00 350 or 450

Bare Length

3. Contact End. The contact end of the electrode shall be clean and free from covering for enabling it to be gripped by the electrode’s holder as specified in Table A2.

Table A2. Bare Length for Various Sizes of electrodes

Electrode Size (in mm) Bare length (in mm)

Minimum Maximum

3.15 15 30

4.0 20 40

4. Arc Striking End. The arc striking end of the electrode shall be bare and permit easy striking of the arc. The distance from the arc end to the first point where the full cross-section of the covering prevails shall not exceed the following

limits; ½ core wire diameter or 2.0 mm, whichever is less.



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Concentricity of Flux Covering with Core Wire-Tolerance

5. The flux covering on the electrode shall be uniform and concentric with the core wire. The tolerance for concentricity of the covering shall be such that the

maximum core plus one covering dimension shall not exceed the minimum core plus one covering dimension by more than 3 percent of the mean of two

dimensions (Fig. A1).

where,

(A-B) ≤ 0.03 x (A+B)/2 A is Maximum core plus one covering dimension, and

B is minimum core plus one covering dimension. (All dimensions in mm)

Fig. A1. Permissible Tolerances for Flux Covering

6. Core wire and coverings shall be free from defects, which would interfere with the uniform welding performance of the electrode.



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Appendix B (Refers to Para 15)

INITIAL TESTS

General

1. The initial tests shall comprise of the following, whose details are given in the succeeding paragraphs:-

(a) The test assembly shall be prepared and tested.

(b) Radiographic quality test from a butt-welded plate.

(c) Three longitudinal all weld metal tensile test from a butt-welded plate.

(d) Three all weld metal charpy impact tests from a butt-welded plate.

(e) Three transverse tensile tests from a butt-welded plate.

(f) Three transverse face and three transverse roots bend tests from a butt-welded plate.

(g) Diffusible hydrogen estimation test.

All Weld Metal Mechanical Tests from butt-welded plates 2. A butt joint configuration as shown in Fig. B1, shall be welded by MMAW

process, using 12mm thick DMR249A steel plates, in vertical up (3G) position. The width of the test plate shall not be less than 150mm and should be along the

rolling direction. 3. The plate edges shall be prepared to form a single V-joint, with an included

angle of 60° and root face of 2mm and 2.5mm root gap. The bevelling of the plate edges shall be carried out by machining or mechanized gas cutting. In the latter

case, any remaining scale shall be removed from the bevelled edges. The bevelled edge of the plate shall be along the transverse rolling direction.

4. The butt weld plates shall be tack welded at three locations, by using 3 Nos. steel restraining plates of dimension (360mm x 50mm x 10mm) as shown in Fig. B1. The tack welds will be made at four different positions for each restraining plate.

5. The plates shall be so preset that they are approximately level after the welding operation has been completed. Butt weld assemblies shall be prepared in

different welding positions as per the Welding Procedure Specification given in Annexure.



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Fig. B1. Schematic diagram of Butt Weld assembly (Joint fit-up)

with restraining pieces



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6. After being welded, the test piece shall not be subjected to any heat treatment.

7. After welding, the test piece shall be cut by sawing or machining to form the required test specimen as indicated in Fig. B2, B3 and B4. The method employed

for the separation of the test specimens shall be such as to cause minimum deformation and minimum heating.

8. The best method is usually by machining. If thermal cutting or other methods which could affect the cut surfaces are used, the cuts shall be made at a distance

from the test specimen greater or equal to 8 mm but in any case sufficient according to the process used, not to induce alterations which could alter the test

results. When the assembly has been welded completely, it shall be allowed to cool in still air to room temperature. The portion including the weld shall then be removed by cutting away the excess plate at the places indicated in Fig. B2, B3 and B4.

9. Cutting along the chain lines (shown by vertical) may be done mechanically or by machine gas cutting. Along the longitudinal boundaries (shown by horizontal broken lines ‘-----’) of the parts to be machined into impact test pieces cutting should be done by mechanical methods only.

10. The yield stress, ultimate tensile strength, percentage elongation and charpy impact strength and diffusible hydrogen content shall comply with the values

given in Table 2. These tests shall be carried out on three different production batches to prove consistency in production. The testing samples shall be drawn

from the plates welded in both flat down hand and vertical up welding positions. Each set of test from Para 1(b) to (f) above shall consist of butt-welded test plates of sufficient length to allow the cutting out of test specimens of the prescribed

number and size.

Radiographic Test

11. All butt-welded test assemblies shall be subjected to radiographic test as per IS:1182. The radiograph shall not show crack or incomplete fusion. The

radiograph acceptance standard in respect of porosity and slag inclusions is indicated in Table B1. In making the evaluation for radiographic acceptance standard, a length of 25 mm of the welded assembly shall be excluded from both

ends.



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Fig. B2. Schematic diagram of location of test specimens

in butt weld assembly



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Table B1. Radiographic Acceptance Standard in Respect

of Porosity and Slag Inclusion

Radiographic Acceptance Standard Grade 1

Type of Porosity and/or Slag Inclusion Assorted

Acceptance Size (in mm) 0.4 to 1.6

Nos. 18

Restriction, if any Large size indications (1.2 to 1.6mm)

≤ 3 no.

Medium size indications (0.8 to 1.2mm)

≤ 5 no.

Small size indications

(0.4 to 0.8mm)

≤ 10 no.

Longitudinal All Weld Tensile Test

12. The tensile test specimen shall be machined from the weld metal test pieces in accordance with IS:1608, care being taken that the longitudinal axis of the test

specimen coincides with the central line of the weld and the mid thickness of the V-groove in the plate (see Fig. B5). The dimensions of the specimen shall be as

shown in Fig. B6. The specimen shall be tested in accordance with IS:1608.

Fig. B5. Location of all weld tensile test specimen in a butt weld plate

All Weld Impact Test

13. Location of impact specimen is given in the Fig. B7. Impact test specimen shall be machined from the weld metal test pieces to the dimensions given in Fig. B8 in accordance with IS:1757. Care to be taken that the longitudinal axis of the specimen is perpendicular to the weld axis and upper surface of the plate. The

notch shall be positioned in the centre of the weld and is to be cut on the face of the test piece perpendicular to the surface of the plate (see Fig. B8) the tests are to be conducted at the test temperature of -50°C on an approved impact machine.



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Fig. B6. Dimensions of all weld tensile test specimen (Round)

Fig. B7. Location of impact test specimen in a butt weld plate

Fig. B8. Dimensions of impact specimen



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14. Two of the three values shall be greater than the specified 50 joules; one of

the three values may be lower but shall not be less than 34 joules. The computed average value of the three values shall be equal to or greater than 50 joules.

Transverse tensile test

15. Location of transverse tensile is given in the Fig. B9. Transverse tensile specimens shall be machined to the dimensions given in Fig. B10. The upper and

lower surface of the weld shall be filed, ground or machined flush with the surface of the plate. Where the surfaces of the plate are not level with each other, the

metal may be cut away to bring them approximately level, provided that the thickness of the plate is not reduced by more than a total of 1 mm. The Ultimate tensile strength of each specimen shall not be less than the specified value in

Table 2.

Fig. B9. Location of transverse tensile test specimen in a butt weld plate

Fig. B10. Dimensions of transverse tensile test specimen



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Butt Weld Bend Test 16. Each bend test specimen shall be 37 mm in width. The location and

dimensions of the bend test specimen are shown in Fig. B11 and Fig. B12 respectively. The upper and lower surface of the weld shall be filed, ground or

machined level with the respective original surface of the plates. Where the surface of the plates are not level with each other, the metal may be cut away to bring them approximately level, provided that the thickness of the plate is not reduced

by more than a total of 1.0mm. Tool marks should be avoided as they lead to localization of stresses and may cause premature failure. For this reason, direction

of machining of surfaces should be along the specimen and transverse of the weld. The sharp corners of the test specimens shall be rounded to a radius not exceeding 10 percent of the specimen thickness.

Fig. B11. Location of root/face bend test specimen in a butt weld plate

Fig. B12. Dimensions of root/face bend test specimen in a butt weld plate



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17. Both type of bend tests, one with face and one with root in tension shall be

carried out from each butt weld assembly. The test specimens shall be bent through 180° over a mandrel having a diameter equal to three times the thickness of the specimen in accordance with IS:1599. The electrode shall be deemed to be

satisfactory, if on completion of the test no crack or defect at the outer surface of the test specimen is greater than 3 mm measured across the test specimen or 1.5

mm measured along the length of the test specimen. Premature failure at comers of the test specimen shall not be considered as a case for rejection.

Diffusible Hydrogen Evaluation Test

18. This test shall be carried out preferably using 3.15 mm size covered electrode. The test shall be carried out in accordance with IS:11802 and mercury

method shall only be used for this determination.

19. The diffusible hydrogen content shall comply with the level given in Table 2.

Retests

20. Where any test specimen fails to fulfil the test requirements, twice the number of the test specimens made for that test for the initial certification or periodic test shall be prepared by using electrode from the same batch wherever

possible and submitted only for the tests in which failure occurred. The electrode shall not be accepted as having passed that test unless the tests on additional

specimen are satisfactory.



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Appendix C (Refers to Para 18)

TEST SAMPLE FOR PERIODIC CHECK TESTS

Fig. C1. Schematic diagram of butt weld assembly for periodic check test



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Appendix D

(Refers to Para 19)

QUALITY CONTROL TESTS

General 1. The various quality control tests are given in the succeeding paragraphs.

All Weld Metal Mechanical Tests 2. By means of a suitable system of control, the manufacturer shall satisfy that

the composition and quality of the filler wire currently produced are similar to the filler wire, which was subjected to initial certification tests. He shall ensure that the result of quality control tests and date of manufacture of filler wires is traced

from the batch number of the relevant details, or both. For the purpose of this standard, a batch is defined as a lot of electrodes of any one size and identified by a heat number of material from single heat of metal. 3. The manufacturer on request shall make available to the approving and

certifying authorities the records maintained for quality control, for ensuring that the composition and quality of all the electrodes currently produced are similar to

those electrodes subjected to initial and periodic check tests.

Weld Metal Assembly

4. A test assembly shall be welded in the flat position. The metal for plates used in preparing test piece shall be of DMR249A having a thickness of 12 mm. The test assembly shall be prepared as shown in Fig. D1 by depositing weld metal

between the chamfered edges of two (plates placed on backing strip). The dimensions of test assembly are given in Table D1. Welding parameters to be used

are as given in Table D2. 5. The backing strip shall be tack welded to test assembly. The backing strip

material shall be DMR249A steel.

6. The dimensions of test assembly are shown in Fig. D1. The length of the plate shall be enough to accommodate a tensile test specimen and three charpy V-notch

test specimens as shown in Fig. D1.



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Table D1. Dimensions of Test Assembly for MMAW

Electrode

Size (in mm)

Plate

Width, C

Plate

Thickness, T

Width of

Welding gap, A

Backing Strip

Width, B (min.)

Thickness, S (min.)

3.15 90±10 15±3 12±1 A±10 > 6.5

4.0 90±10 20±2 16±1 A±10 > 10.0

7. The plate’s edges shall be bevelled by machining or machine gas cutting. In

the later case any remaining scale should be removed from the bevelled edges. The surface of the backing strip should be free from rust or scale.

Table D2. Welding Parameters for MMAW

Welding Parameters Unit Range/Values

Electrode Size mm 3.15 4.0

Arc Voltage V 22-26 24-26

Welding Current A 90-100 120-135

Type of Current - DCRP DCRP

Travel Speed mm/sec 1.5-2.0 1.5-2.0

Inter-pass Temperature ºC 150 150

8. In order to counteract shrinkage deformation the test assembly should be

tack welded so that a level joint is obtained after welding.

9. Cutting of test assembly for preparing test specimen should be done as per Para 7 of Appendix B.

All weld Tensile Test

10. Location of all weld tensile test piece is shown Fig. D2. Tensile test piece shall be prepared in accordance with Fig. B6. The tensile properties shall comply with

values given in Table 2.

All Weld Impact Test

11. Three charpy V-notch test specimens shall be machined in accordance with Fig. B8. Samples should be tested as per Para 13 of Appendix B and shall comply

with values given in Table 2.



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Fig. D1. Schematic diagram of Butt weld assembly (Joint fit-up)

for quality control test



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where T is as per Table D1.

Fig. D2. Location of all weld tensile test specimen

for quality control test

All weld chemical composition

12. For chemical analysis the mid-section of the chemical analysis pad can be

used, Fig. D1, provided diluted weld metal is avoided. As an alternative the broken tensile test specimen can also be used for chemical analysis. The results of the analysis shall meet the requirements as agreed to in Quality Assurance Plan

(QAP).

Diffusible Hydrogen Evaluation Test

13. Diffusible hydrogen estimation test shall be done as per Para 18 of Appendix B.



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Appendix E (Refers to Para 26)

APPROVED SOURCES

S.No. Product Name Contact Details

1. 48XN4 electrodes

M/s Mishra Dhatu Nigam Limited P.O. Kanchanbagh Hyderabad-500 058

Andhra Pradesh Telephone. 040-24340293, 24340253, 24340634

Fax. 040-24341250, 24340214, 24340764 E-mail. [email protected]

\Website. www.midhani.com

2. Unimate-1 electrodes

M/s Honavar Electrodes Limited 305-309, 3rd Floor Damji Shamji Industrial Complex

9, LBS Marg, Kurla (East) Mumbai-400 070 Maharashtra

Telephone. 022-2502 0317, 2502 1238

Fax. 022-2510 0048 E-mail. [email protected]

3. Giriduct-100 electrodes

M/s GEE Limited Plot No. E-1, Road No. 7

Wagle Industrial Estate Thane-400 604 Maharashtra

Telephone. 022-25821277, 25820619, 25822620

Fax. 022-25828938 E-mail. [email protected]

mailto:[email protected]

http://www.midhani.com/





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S.No. Product Name Contact Details

4. DK18Ni(MOD) electrodes

M/s Dwekam Electrodes Ltd. Talawali Chanda

PO Manglia-453 771 AB Road

Dist. Indore Madhya Pradesh

Telephone. 0731-5021442, 5021490 Fax. 0731-5021441

E-mail. [email protected]




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Annexure (Refers to Para 5 of Appendix B)

WELDING PROCEDURE SPECIFICATION

Company Name ...... Reference NCD 1501

Welding process MMAW Issue 1

Process type Manual Authorised by IHQ, MoD(N)

Joint Design Used Position

Joint type Butt joint Welding Position 3G Butt

Joint Design Single V

Root Opening 2.5 mm Electrical Characteristics

Root Face 2.0 mm Current DC

Groove Angle 60° Polarity EP

Back Gouging Yes Technique

Back gouging method Grinding Type of bead Stringer bead

Base Metal Passes per side Multiple passes

Material Specs NCD 0249

Type or Grade DMR249A Steel Inter-pass cleaning Brushing & grinding

Thickness 12.0 mm

Filler Metals Preheat

Product Code Unimate-1 Preheat temp. Nil

Griduct-100 Inter-pass temp. 150°C

DK18Ni(MOD)

Baking Cycle 450 °C/2 hr.

Welding Procedure Process: MMAW

Pass or Weld

Layer(s)

Filler Metal Dia.

(mm)

Current Volts Travel Speed (mm/

sec.)

Heat Input

(kJ/mm)

Joint Details

Type & Polarity

Amps

1 (Root) 3.15 DC+ 80-90 24-26 1.1-1.3 1.4-2.0

2 4.0 DC+ 100-120 24-26 1.4-1.8 1.4-2.0

3 4.0 DC+ 120-135 24-26 3.5-4.5 0.6-1.0

4 4.0 DC+ 120-135 24-26 1.5-2.5 1.2-2.2



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N O T E S