Welding Sepe Piping
Welding Sepe Piping
_1/U-, a_-, l_
REVISED & REISSUED AS STANDARD P CHOWDHARY S GHOSAL P P LAHIRI SCHANDA
4 8/07/14
SPECIFICATION
REVISED & REISSUED AS STANDARD
3 28/12/07 SPECIFICATION MPJ VRK VRK vc
REVISED TO INCLUDE CHECK
2 08/02,02 RADIOGRAPHY GC RN TVD
REVISED & REISSUED AS STANDARD
15/05/98 SPECIFICATION
MPJ TVD JRP AS
ISSUED AS STANDARD
0 31/07/87 SPECIFICATION
TVD TVD JRP AK
Standards Standards
Rev. Committee Bureau
Date Purpose Prepared by Checked by
No Convenor Chairman
Aeeroved br
Page 1 of 5335
.!.id ENGINEERS STANDARD SPECIFICATION No.
WINDIA
LIMTED WELDING SPECIFICATION FOR 6-77-0001 Rev. 4
IMli?'l'l' ml,JIR!ifH iAGo-..1 of India Undet'lall1ng) FABRICATION OF PIPING
Page 2 of 40
ABBREVIATIONS
RT Radiographic Testing
Page 2 of 5335
STANDARD SPECIFICATION No.
WELDING SPECIFICATION FOR
FABRICATION OF PIPING 6-77-0001 Rev. 4
Page 3 of 40
CONTENTS
1.0 GENERAL...........................................................................................................................................4
2.0 APPLICABLE CODES & STANDARDS........................................................................................4
3.0 BASE METAL....................................................................................................................................5
4.0 WELDING CONSUMABLES............................................................................................................5
5.0 SHIELDING & PURGING GAS.......................................................................................................5
6.0 EQUIPMENTS & ACCESSORIES..................................................................................................6
7.0 WELDING PROCESS.......................................................................................................................6
8.0 EDGE PREPARATION.....................................................................................................................6
9.0 ALIGNMENT & SPACING..............................................................................................................7
10.0 WEATHER CONDITIONS.................................................................................................................7
11.0 WELDING TECHNIQUE...................................................................................................................7
12.0 HEAT TREATMENT.........................................................................................................................8
13.0 CLEANING OF THE WELD JOINT.............................................................................................10
14.0 INSPECTION AND TESTING.......................................................................................................10
15.0 REPAIRS OF WELDS.....................................................................................................................14
16.0 DOCUMENTS TO BE SUBMITTED BY CONTRACTOR (4 COPIES EACH).....................14
EXHIBIT - A: ELECTRODE QUALIFICATION TEST RECORD.......................................................16
EXHIBIT- B: STRESS RELIEF HEAT TREATMENT PROCEDURE SPECIFICATION.................20
EXHIBIT-D: FORMAT FOR PROCEDURE QUALIFICATION RECORD (PQR).............................24
EXHIBIT - E: FORMAT FOR MANUFACTURER'S RECORD FOR WELDER OR WELDING
OPERATOR QUALIFICATION TESTS...................................................................................................27
EXHIBIT - F: RADIOGRAPHIC PROCEDURE QUALIFICATION RECORD FOR PIPE
WELDING.....................................................................................................................................................29
EXHIBIT - G: WELDER'S IDENTIFICATION CARD.........................................................................30
EXHIBIT - H: TYPE OF SOURCE AND FILMS TO BE USED FOR RADIOGRAPHY..................31
EXHIBIT- I: AUTOMATED ULTRASONIC TESTING........................................................................32
Page 3 of 5335
WELDING SPECIFICATION FOR STANDARD SPECIFICATION No.
FABRICATION OF PIPING
6-77-0001 Rev. 4
Page 4 of 40
1.0 GENERAL
This specification shall be followed for the fabrication of all types of welded joints of piping
system within the battery limits of the plant. This specification shall be used in conjunction with
Welding Specification Charts.
a) All pipe joints, longitudinal butt welds, circumferential butt welds and socket welds.
f) The attachments of smaller connections for vents, drain drips and other instrument tappings.
Any approval granted by the Engineer-in-Charge or Owner's inspector, shall not relieve the
Contractor of his responsibilities and guarantee.
This specification shall not be applicable for welding of pipelines for transportation of liquid
petroleum , gas and other similar products in on shore and off shore.
i) ASME B3l .3: Process Piping, ASME Code for Pressure Piping, B3l
ii) ASME Boiler & Pressure Vessel Code, Sec II Part C: Specifications for Welding Rods,
Electrodes and Filler metals.
iii)ASME Boiler & Pressure Vessel Code, Section V: Non destructive examination.
iv) ASME Boiler & Pressure Vessel Code, Section IX: Welding and Brazing Qualifications.
viii) API 582: Welding Guidelines for the Chemical, Oil, and Gas Industries.
In the event of any differences due to the additional requirements mentioned in this
specification, over and above those obligatory as per codes, this specification shall be binding.
Page 4 of 5335
ENGINEERS STANDARD SPECIFICATION No.
WELDING SPECIFICATION FOR
INOIA LIMITED FABRICATION OF PIPING 6-77-0001 Rev. 4
Page 5 of 40
3.2 The Contractor shall provide the manufacturer's test certificates for every batch of the
materials supplied by him.
4.2 The welding electrodes and filler wires supplied by the Contractor shall conform to the class
specified in the Welding Specification Chart. The materials shall be of the make approved by
the Engineer-in-Charge.
4.3 Electrode qualification test records should be submitted as per the Exhibit-A (attached) in
respect of the electrodes tested by the Contractor, for obtaining the approval of the Engineer
in-Charge. It shall record the minimum test results required for classification of welding
consumables as per ASME Section II part C.
4.4 The Contractor shall submit batch test certificates from the electrode manufacturers.
4.5 All electrodes shall be purchased in sealed containers and stored properly to prevent
deterioration. The electrodes removed from the containers shall be kept in baking ovens at
temperatures recommended by the electrode manufacturer. "Out of the oven time" of
electrodes, before they are consumed, shall not exceed the limits recommended by the
electrode manufacturer. The electrodes shall be handled with care to avoid any damage to the
flux covering.
4.6 All low hydrogen type of electrodes and others, shall be baked as per manufacturers
recommendation and stored in holding ovens at temperature recommended by the
manufacturer.
4.7 The electrodes, filler wires and flux used shall be free from rust, oil, grease, earth and other
foreign matter which affect the quality of welding.
5.2 Argon gas with a purity level of minimum 99.995% shall be used for purging.
5.3 When GTA W process alone or a combination of GTA W and SMAW processes is
recommended for the production of a particular joint, the purging shall be maintained during
the root pass and for thl.': first filling pass to minimize oxidation on the inner side of th pipe,
unless otherwise specified in Welding Specification Chart.
5.4 Initial purging shall be maintained for sufficient period of time so that at least 4-5 times the
volume between the dams is displaced, in order to completely remove the entrapped air. In no
case should the initial purging period be less than IO minutes. High gas pressure should be
avoided.
Page 5 of 5335
,!Jd A.ENGINEERS STANDARD SPECIFICATION No.
WINDIA WELDING SPECIFICATION FOR
LIMITED 6-77-0001 Rev. 4
FABRICATION OF PIPING
• ffll,JIJOl"ltl fAGo..-t of lnoia Unctef1at(1ng)
Page 6 of 40
5.5 After initial purging, the flow of the backing gas should be reduced to a point where only a
slight positive pressure prevails.
5.6 Gas backing (purging) is not required for socket type of welded joints.
5.7 Dams, used for conserving inert gas during purging, shall be removed after completion of the
welding, and shall be accounted for. Wherever, removal of dams is not possible after welding,
use of water-soluble dams should be made.
6.2 Contractor shall make necessary arrangements at his own expense, for providing the
radiographic equipments, radiographic films, processing equipment all other darkroom
facilities and all the equipments/materials required for carrying out the dye-penetrant/magnetic
particle test/ultrasonic testing.
7.2 In addition to Shielded Metal Arc Welding Process (SMAW) and Gas Tungsten Arc Welding
Process (GTAW), Welding of various materials under this specification may be carried out
using one or more of the following processes with the approval of the Engineer-in-Charge.
7.3 The Welding procedure could be employed for a particular joint only after duly qualifying the
welding procedure to be adopted.
The edges to be welded shall be prepared to meet the joint design requirements by any of the
following methods recommended:
(c) High alloy steel(> 5% Chromium) and stainless steels, nickel alloys:
Plasma cutting, machining or grinding methods shall be used. After plasma cutting,
cut surfaces shall be machined or ground smooth.
Page 6 of 5335
ENGINEERS STANDARD SPECIFICATION No.
INDIAUMITED WELDING SPECIFICATION FOR 6-77-0001 Rev. 4
FABRICATION OF PIPING
Page 7 of 40
8.2 Cleaning
(a) The ends to be welded shall be properly cleaned to remove paint, oil, grease, rust,
oxides, sand, earth and other foreign matter. The ends shall be completely dry before
the welding commences.
(b) On completion of each run, craters, welding irregularities, slag etc., shall be removed
by grinding and chiseling. Wire brushes used for cleaning stainless steel joints shall
have stainless steel wires and the grinding wheels used for grinding stainless steel
shall be of a suitable type. Separate grinding wheels and wire brushes should be used
for carbon steels and stainless steels.
9.2 A wire spacer of suitable diameter may be used for maintaining the weld root opening while
tacking, but it must be removed after tack welding and before laying the root bead.
9.3 For pipes of wall thickness 5 mm and above, the ends to be welded shall be secured in position
with the aid of couplers, yokes and 'C' clamps, to maintain perfect alignment. Yokes shall be
detached after the completion of weld, without causing any surface irregularity. Any
irregularity caused on the pipe surface must be suitably repaired to the satisfaction of the
Engineer-in-Charge.
9.4 Tack welds, for maintaining the alignment, of pipe joints shall be made only by qualified
welders using approved WPS. Since the tack welds become part of the final weldment they
shall be executed carefully and shall be free from defects. Defective tack welds must be
removed prior to the actual welding of the joints.
9.5 Tacks should be equally spaced. Minimum number of tacks shall be:
9.6 Welding shall commence only after approval of fit-up by the Engineer-In-Charge.
10.2 During field welding using GTAW process, particular care shall be exercised to prevent any
air current affecting the welding process.
(a) Root pass shall be made with electrodes/filler wires recommended in the welding
specification chart. For fillet welding, root welding shall be done with consumables
recommended for filler passes. The preferred size of the electrodes is 2.5 mm
diameter (12 SWG) but in any case not greater than 3.25 mm (10 SWG).
Format No. 8-00-0001-F1 Rev. o Copyright Ell -All rights reserved
Page 7 of 5335
-!Jd ENGINEERS STANDARD SPECIFICATION No.
'WINDIA WELDING SPECIFICATION FOR
LIMITED 6-77-0001 Rev. 4
FABRICATION OF PIPING
1 12'1 1 !AGo..tofll'ldial.ln<tertaklng)
Page 8 of 40
(b) Upward technique shall be adopted for welding pipe held fixed with its axis
horizontal.
(c) The root pass of butt joints should be executed so as to achieve full penetration with
complete fusion of the root edges. Weld projection inside the pipe shall be as per
applicable code. It shall be limited 3mm max. when the applicable code does not
place any restriction.
(d) Any deviation desired from the recommended welding technique and electrodes
indicated in the welding specification chart should be adopted only after obtaining
express approval of the Engineer-in-Charge.
(f) While the welding is in progress care should be taken to avoid any kind of movement
of the components, shocks, vibrations and stresses to prevent occurrence of weld
cracks.
(a) Joint shall be completed using the class of electrodes, recommended in the Welding
Specification Chart. Size of the electrode shall not exceed 4 mm in diameter for
stainless steels and alloy steels used for low temperature applications.
(b) Two weld beads shall not be started at the same point in different layers.
(c) Butt joints shall be completed with a cover layer that would affect good fusion at the
joint edges and a gradual notch free surface.
(d) Each weld joint shall have a workmanship like finish. Weld identification work shall
be stamped clearly at each joint, just adjacent to the weld. Metal stamping shall not be
used on thin pipe having wall thickness less than 3.5mm. Suitable paint shall be used
on thin wall pipes for identification.
(e) Rust preventive/protective painting shall be done after the weld joint has been
approved.
Where welds are to be produced between carbon steels and alloy steels, preheat and post weld
heat treatment requirements shall be those specified for corresponding alloy steels and filler
wire/electrodes shall correspond to ER70S-2 or E-7016/7018 type. For welds between two
dissimilar Cr-Mo low alloy steels, preheat and post weld heat treatments shall be those
specified for higher alloy steel and electrodes used shall correspond to those specified for steel
of lower alloy content. For carbon steel or alloy steel to stainless welds, use of filler
wire/electrodes E/ER-309/ERNiCr-3/E Ni Cr Fe-3/ENiCrMo-3 shall be made. The welding
procedure, electrodes/filler wires to be used shall be approved by the Engineer-in-Charge.
(a) No welding shall be performed without preheating the joint to 10°C (50°F) when the
ambient temperature is below 10 degree.
Format No. 8-00-0001-F1 Rev. 0 Copyright Ell - All rights reserved
Page 8 of 5335
STANDARD SPECIFICATION No.
WELDING SPECIFICATION FOR
FABRICATION OF PIPING 6-77-0001 Rev. 4
Page 9 of 40
(b) Preheating requirements for the various materials shall be as per the Welding
Specification Chart attached.
(d) Preheating shall extend uniformly to at least three times the thickness of the joint, but
not less than 25 mm, on each sides of the weld.
(e) Preheating temperature shall be maintained over the whole length of the joint during
welding. Temperature recorders shall be provided by the Contractor to record the
temperature during alloy steel welding. For carbon steel piping, preheat temperature
shall be ensured by use of temperature indicating crayons, pyrometers or other suitable
means.
In case of alloy steel materials such as Cr-Mo steels, if the post weld heat treatment is not
performed immediately after welding, the weld joint and adjacent portion of pipe, at least 50
mm on either side of weld, shall be uniformly heated to 300°C. This temperature shall be
maintained for half an hour minimum, and then wrapped with mineral wool before allowing it
to cool to room temperature. If the Post Heating temperature specified in the Welding
Specification Charts exceeds 300°C, the same shall be followed. Similarly, if the welding
specification chart specifies post-heat time, the same shall be applicable. Post weld heat
treatment as specified in the Welding Specification Chart shall be carried out later on.
(a) Post weld heat treatment, wherever required for joints between pipes, pipes and
fittings, pipe body and supports shall be carried out as per the welding specification
chart, applicable codes standards and the instructions of the Engineer-in-Charge. In
this regard procedure qualification to be done before carrying out PWHT in
production welds
(b) The Contractor shall submit for the approval of the Engineer-in-Charge, well before
carrying out actual heat treatment, the details of the post weld heat treatment
procedure as per Exhibit B attached, that he proposes to adopt for each of the
materials/assembly/part involved.
(c) Post weld heat treatment shall be done in a furnace or by using an electric resistance or
induction-heating equipment, as decided by the Engineer-in-Charge.
(d) While carrying out local post weld heat treatment, technique of application of heat
must ensure uniform temperature attainment at all points of the portion being heat
treated. Care shall be taken to ensure that width of heated band over which specified
post weld heat treatment temperature attained is at least that specified in the relevant
applicable standards/codes. Control of temperature shall be done using
microprocessor/computer controlled system. The desired time-temperature cycle shall
be entered into the microprocessor/computer.
(e) Throughout the cycle of heat treatment, the portion outside the heated band shall be
suitably wrapped under insulation so as to avoid any harmful temperature gradient at
the exposed surface of pipe. For this purpose temperature at the exposed surface
should not be allowed to exceed 50% of the peak temperature.
Page 9 of 5335
d ENGll'ffRS STANDARD SPECIFICATION No.
• WINDIAUMTED
l,Ml!\"l"J ml'JIJIIQl.1 1AGo,,t dirdal..ndeftakll'lg)
WELDING SPECIFICATION FOR 6-77-0001 Rev. 4
FABRICATION OF PIPING
Page 10 of 40
(f) The temperature attained by the portion under heat treatment shall be recorded by
means of thermocouple pyrometers. Adequate number of thermocouples should be
attached to the pipe directly at equally spaced location along the periphery of the pipe
joint. The minimum number of thermocouples attached per joint shall be 1 up to 6"
dia., 2 up to 10" dia. and 3 for 12" dia. and above. However, the Engineer-in-Charge
can increase the required number of thermocouples to be attached if found necessary.
(g) Automatic temperature recorders, which have been suitably calibrated, shall be
employed for measuring & recording temperature. The time-temp graph shall be
submitted to Engineer-in-Charge immediately on completion of Stress Relieving
Cycle The calibration record of each recorder should be submitted to the Engineer-in
Charge prior to starting the heat treatment operations and his approval should be
obtained.
(h) Manufacturer's test certificate shall be submitted for the thermocouples materials and
record shall be maintained by the Contractor.
(i) Immediately on completion of the Heat Treatment, the Post Weld Heat Treatment
charts/records along with the hardness test results on the weld points, wherever
required as per the Welding Specification Chart, shall be submitted to Engineer-in
Charge for his approval.
G) Each weld joint shall bear a unique identification number, which shall be maintained
in the piping sketch to be prepared by the Contractor. The weld joint identification
number should appear on the corresponding post weld heat treatment charts. The
chart containing the identification numbers and piping sketch shall be submitted to the
Engineer-in-Charge in suitable folders.
(a) The Owner's inspector shall have free access to all concerned areas, where the actual
work is being performed. The contractor shall also accord the Owner's Inspector all
means and facilities necessary to carry out inspection.
(b) The Owner is entitled to depute his own inspector to the shop or field where
prefabrication and erection of pipe lines is in progress for (but not limited to) the
following objectives:
iv) To check whether shop/field welding being executed is in conformity with the
relevant specifications and codes of practice followed in piping construction.
Page 10 of 5335
ENGINEERS STANDARD SPECIFICATION No.
INOIA LIMITED WELDING SPECIFICATION FOR
FABRICATION OF PIPING 6-77-0001 Rev. 4
Page 11 of 40
Welding procedure qualification shall be carried out in accordance with the applicable
requirements of ASME Sec. IX latest edition and/or other applicable codes and the job
requirements. The contractor shall submit the welding procedure specification in format as per
Exhibit-C (attached) immediately after the receipt of the order. Owner's inspector will review,
check and approve the welding procedure submitted and shall release the procedure for
qualification tests. The procedure qualification test shall be carried out by the Contractor at
his own expense. A complete set of test results in the format as per Exhibit-D attached) shall
be submitted to the Owner's inspector for his approval immediately after completing the
procedure qualification test and at least 2 weeks before the commencement of actual work.
Standard test as specified in the code shall be carried out in all cases. In addition to these tests,
other tests like macro/micro examination, hardness tests, dye penetrant examination, charpy V
notch, Corrosion tests, impact tests etc. shall be carried out on specimens depending upon the
type of base material, operating conditions and requirements laid down in the detailed
drawings and specifications. It shall be the responsibility of the Contractor to carry out all the
tests required to the satisfaction of the Owner's inspector.
(a) Welders shall be qualified in accordance with the ASME Section-IX or other
applicable codes. The Owners inspector reserves the right to witness the test and
certify/approve the qualification of each welder separately. Only those welders who
have been approved by the Owner's Inspector shall be employed for welding.
Contractor shall submit the welder qualification test reports in the format as per
Exhibit-E (attached) and obtain express approval before commencement of work.
It shall be the responsibility of
Contractor to carry out qualification tests of welders. For welding of the steam piping,
falling under the purview of Indian Boiler Regulations, only those welders with IBR
Certification, qualified by Boiler Inspectorate, and acceptable to the local Boiler
Inspector authority shall be employed.
(b) The welders shall always have in their possession, an identification card containing
information contained in Exhibit-G and shall produce it on demand by the Engineert
In-Charge or his representative. It shall be the responsibility of the Contractor to issue
the identify cards after it has been duly certified by the, owner's Inspector.
(c) No welder shall be permitted to work without the possession of the identify card.
(d) If a welder is found to perform a type of welding or in a position for which he is not
qualified, he shall be debarred from doing any further work. All welds performed by
an unqualified welder shall be cut and redone by a qualified welder at the expense of
the Contractor
Visual Examination of all welds shall be carried out as per the latest editions of the applicable
codes and specifications. All finished welds shall be visually inspected for parallel and axial
alignment of the work, excessive reinforcement, concavity of welds, shrinkage cracks,
inadequate penetration, unrepaired bum-through, under cuts, dimensions of the weld, surface
porosity and other surface defects. Undercutting adjacent to the completed weld shall not
exceed the limits specified in the applicable standard/code.
Format No. 8-00-0001-F1 Rev. 0 Copyright Ell - All rights reserved
Page 11 of 5335
d ENGINEERS STANDARD SPECIFICATION No.
WINDIA UMTED
l ffl'JlrOA'll IAGo t olniia ngt WELDING SPECIFICATION FOR 6-77-0001 Rev. 4
FABRICATION OF PIPING
Page 12 of 40
(c) Type of Radiation source and film to be used shall be as per Exhibit-H for carrying out
radiographic examination. However if specifications (as given else where in the
contract) for some critical material require usage of X-Radiation, then Radiography
shall be done using X-Rays only.
(d) The Contractor shall fulfill all the statutory and owner's safety requirements while
handling X-ray and Gamma-ray equipments.
(e) In case of random radiography, the joints for Radiography shall be selected by the
Owner's Inspector and the Radiography shall be performed in his presence, if he
instructs the contractor to do so. The contractor shall furnish all the radiographs, to the
Owner's Inspector immediately after processing along with evaluation by a person
qualified to ASNT Level-II in Radiographic testing, inline with Article 2 of ASME
Sec.V. The certificate of ASNT/ISNT Level II qualification of the NDT personnel
shall be submitted to owner's inspector for his approval prior to start of job.
(f) The Contractor shall provide the Owner's Inspector, all the necessary facilities at site
such as a dark room with controlled temperature, illuminator (viewer) suitable for
varying densities, a duly calibrated electronic densitometer with batteries, magnifying
glass, tracing papers, ruler, marking pencils etc. to enable him to review the
radiographs.
(g) Where random radiography is specified, the first weld of each welder shall be
completely radiographed. In the case of pipe of size 6" and below, the first two welds
shall be completely radiographed.
(h) For each weld performed by a welder found unacceptable, two additional checks shall
be carried out on welds performed by the same welder. This operation is iterative and
the of two additional welds for each weld deemed unsatisfactory shall be continued till
such time that two consecutive welds of satisfactory quality are found for every
defective weld.
(i) The Contractor shall carry out these additional radiographic testing at his own
expense. To avoid the possibility of too many defective welds by a single welder
Format No. 8-00-0001-F1 Rev. O Copyright Ell - All rights reserved
Page 12 of 5335
ENGINEERS STANDARD SPECIFICATION No.
INDIAUMITED WELDING SPECIFICATION FOR
FABRICATION OF PIPING 6-77-0001 Rev. 4
Page 13 of 40
remaining undetected for a long period to time, the Contractor shall promptly arrange
for Radiographic Examination so that there is no accumulation of defective joints.
(j) Contractor shall quote rates for X-ray as well as Gamma Ray for joints indicated to be
radiographed by X-ray in Table ofExhibit-H.
(a) Owner I Engineer- in- charge or his representative shall select 5% of the total joints
radiographed on a day for check shots. Contractor shall carry out check shots as
directed.
(b) Weld profiles of check shots shall be compared with weld profile observed in the
earlier Radiographs. In the event of any one variation in the check shots and earlier
Radiographs, contractor shall re-shoot the entire lot of joints radiographed by
particular Radiography agency on the particular date. All the re-shot films shall be
compared with the originally submitted films.
(a) Whenever such tests are specified, the tests shall be carried out on joints chosen by the
Owner's inspector, as per ASME Section V article 6 and 7 respectively. The tests are
to be performed by a person possessing a valid ASNT/ISNT Level-II qualification in
the method being used.
(b) For austenitic stainless steels and other nonmagnetic materials, liquid (dye) penetrant
test shall be carried out. For carrying out this test, the materials shall be brought
within a temperature limit of I 5° to so c.
0
(b) The automated ultrasonic testing (AUT) procedure to be adopted shall be submitted by
the CONTRACTOR as per EXHIBIT-I and get it approved from EIL/OWNER.
(c) The CONTRACTOR shall make all the arrangements for the Automated Ultrasonic
Testing of work at his expense. The CONTRACTOR shall furnish all the reports to the
EIL/OWNER, immediately after examination together with the corresponding
interpretation reports on the approved format. The details of the AUT reports along
with the joint identification number shall be duly entered in a register and signed by
the CONTRACTOR and submitted to the EIL/OWNER for approval. The
EIL/OWNER will review all the Automatic Ultrasonic Testing records of welds and
inform the CONTRACTOR to those welds, which are unacceptable. The decision of
the COMPANY shall be final and binding in this regard.
(d) In addition, Radiography examination shall be carried out when in the opinion of
EI.;: ,/oWNER, Radiography inspection is required to confirm or clarify defects
indicated by Automated Ultrasonic examination. Repaired welds and transition spool
piece weld joints shall be additionally examined by radiography if it is examined by
automated ultrasonic testing.
(e) The automated ultrasonic testing system used for inspecting welds shall be approved by
EIL/OWNER.
Page 13 of 5335
..!Jd ENGINEERS STANDARD SPECIFICATION No.
s'WINOIA UMTED WELDING SPECIFICATION FOR
lffl?l"f mf,J!Jtfl'Jll IAGo\rt.ofil'\OiaUndeftaking) 6-77-0001 Rev. 4
FABRICATION OF PIPING
Page 14 of 40
Hardness requirements for welds shall be as per the Welding Specification Chart/Non
Destructive Examination Specification attached elsewhere in the contract. Hardness testing
shall be carried out by Vickers Hardness Tester during welding procedure qualification and
shall be cross sectional. For production welds, hardness testing shall be carried out by portable
digital hardness testers. Poldi hardness tester shall not be permitted. Contractor shall produce
documentary evidence/calibration certificate to the Owner's Inspector and obtain approval of
the hardness testing equipment.
Hydrostatic and pneumatic tests shall be performed as per the requirements laid down by
respective flushing and Testing specification/applicable codes to demonstrate the soundness of
the welds. The tests shall be conducted after fulfilling the requirement of visual examinations
radiography etc., and after the entire work has been certified by the Owner's inspector to be fit
for being subjected to such tests.
(b) Repairs and/or work of defective welds shall be done in time to avoid difficulties in
meeting the construction schedules.
(c) Defects ascertained through the inspection methods, which are beyond acceptable limits
shall be removed after the joint is completely radiographed by the process of chipping
and grinding. The repaired welds shall be subjected, as a minimum requirement to the
same testing and inspection requirements as the original weld.
(d) The number of times repair welding can be permitted for the same weld shall be
governed by the standard specification, 6-44-0016.
When the entire joint is judged unacceptable, the welding shall be completely cut and edges suitably prepared
as per required alignment tolerances. The rewelded joint shall again be examined following standard practices.
Page 14 of 5335