Date : 15.07.2011 Revision : 02 Page : 1/13
FABRICATION MT!OD "TATMNT
ATA# ATA# N$INRIN$ CON"TR%CTION CON"TR%CTIO N TRAD INC. CO.
Rev. 00
P&e'a&e( B)
A''&ove( B)
"ign
Date : 15.07.2011 Revision : 02 Page : 2/13
TAB* OF CONTNT" 1.0
"COP OF +OR#
,
2.0
PRO$RAMM
,
3.0
MATRIA*"
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3.1
MATRIA* "% "%PP*-
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3.2 3.2
MAT MATRIA RIA* * IDN IDNTI TIFI FICA CAT TION AND TRAC TRACA ABI BI*I *ITT-
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3.3
RA+ MATRIA* IA* T"TIN$
5
MT!OD "%NC OF OF T! T! +O +OR#
5
,.1
FABRICATION
5
,.2
FABRICATION PR PROC""
0
,.2.1 .2.1
C%TT %TTIN$ IN$ P*A P*AN N"
0
,.2.2
MAR#IN$
0
,.2.3
C%TTIN$
7
,.2., .2.,
"TRA TRAI$! I$!TNIN NIN$ $
7
,.2.5
BNDIN$
7
,.2.
!O*"
1
,.2.7
NOTC!"
2
,.2.
A""MB*-
10
,.2.
BO*TIN$
10
,.2.10 +*DIN$
10
,.2.10.1
D$ PRPARATION IN"PCTION
10
,.2.10.2
FIT%P A""MB*-
10
,.2.10.3
BAC#IN$ "TRIP IN"PCTION
11
,.2.10.,
+*DIN$ PROC""
11
,.2.10.,.1 T-P OF +*DIN$ PROC""
11
,.2.10.,.2 *CTROD"
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,.2.10.,.3 ,.2.10.,. 3 PR!AT AND INTRPA"" TMPRAT%R TMPRAT%R
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,.2.10.,., "%NC OF +*DIN$ 4CONTRO* OF DI"TORTION AND "!RIN#A$
2
,.2.10.,.5 ,.2.10.,. 5 6I"%A* AMINATION OF +*D"
2
,.2.11 PR PROCD%R FOR B%I*T %P $IRDR" / BAM"
1013
,.2.11.1
PRPARATION OF MATRIA*
10
,.2.11.2
FIT%P A""MB*-
11
,.2.11.3
+*DIN$ PROC""
11
,.2.12 NOND"TR%CTI6 T"TIN$ 4NDT
12 Date : 15.07.2011 Revision : 02 Page : 3/13
4.2.12.1$NRA* 4.2.12.1 $NRA* R%IRMNT R%IRMNT OF 6I"%A* IN"PCTION
,.2.12.2$NRA* R%IRMNT" OF *I%ID PNTRANT T"TIN$ ,.2.12.3$NRA* R%IRMNT" OF MA$NTIC PARTIC* PARTIC* T"TIN$ ,.2.12.,$NRA* R%IR.OF %*TRA"ONIC AMINATION 5.0
DIMN"IONA* IN"PCTI ON
12
6.1
PROTCTION
12
6.2
"AND B*A"TIN$
12
6.3
PAINTIN PAINT IN$ $ APP APP*I *ICATIO CATION N
13
7.0
PAC#IN$ AND D*I6R-
13
.0
IN"PCTION AND T"T P*AN
13 Date : 15.07.2011 Revision : 02 Page : ,/13
1.0 "COP OF +OR# The purpose of this procedure is to describe the fabrication methods, welding techniques, quality assurance and quality inspections to be carried out about welding, weld repair and weld inspections for T! "ngineering #onstruction $ndustry #o. $nc. 2.0 PRO$RAMM %rogramme for &abrication wor's refer to T! (tructural (teel wor's %rogramme. 3.1 MATRIA*" 3.2 Mate&ia8 Mate&ia8 "9''8) The quality of materials should be according to #ustomer specifications and drawings. The )rade of structural steel shall conform to "uropean (tandard "* 1002+ as noted on the drawings with minimum yield strength as specified below The steel shall be free from loose mill scale, surface defects, fla'y rust, slag inclusions, laminations, pitting and be of full weight or thic'ness within tolerances specified in standard. ppro-ed (teel suppliers will be used. s a normal practice mill certificates will be made a-ailable for steel ordered. (ubstitution if any, on sies or quality shall be implemented only after obtaining appro-al from the /wner "ngineer. ll steel supplied shall be stored in a safe condition with proper care ta'en during storage to ensure that no damage occurs, which renders the materials unser-iceable. unser-iceable. ll steel material shall be stored at the shopyard abo-e the ground on the platforms, s'ids or concrete bloc's. aterials for this proect shall be mar'ed differently from the other proect material. The identifying and mar'ing system shall be established. ll steel material procured shall be properly documented to ensure conformity to specifications and it shall be the responsibility of the control foreman or staff to ensure conformity of steel to the specifications. specifications.
3.2. Mate&ia8 I(entii;ation an( T&a;ea
The &abrication "ngineers &oreman shall be responsible to arrange to mar' the $tem number and punch the material code number on each member. 4.1 MT!OD "%NC OF T! +OR# ,.2 Fa<&i; Fa<&i;ati ation on The fabrication of steel wor's shall be carried out as per appro-ed drawings and specification pro-ided by T!. The method and sequence of fabrication is gi-en in the following chapters. 4.3 Fa<&i;ation P&o;ess ,.3.1 ,.3.1 C9tting C9tting P8ans P8ans The cutting cutting plan shall be prepared prepared for all material material before before commenceme commencement nt of fabricatio fabrication n
wor'. wor'.
aterial mar' number shall be pro-ided for easy identification. identification. 4.3.2 Ma&=ing ar'ing shall be carried out as per appro-ed cutting plan under the guide lines of fabrication foremen, and subsequently -erified by the &abrication engineer prior to cutting. %rior to mar'ing the material shall be chec'ed for its identification and the defects. *ecessary items shall be carefully and accurately mar'ed in accordance with appro-ed shop drawings or templates. 4.3.3 C9tting ateri aterial al cutti cutting ng shall shall be carrie carried d out out either either by shear shear,, plasma plasma,, #*# #*# %rofil %rofile e cuttin cutting g and and drilli drilling ng machin machine, e, pug cuttin cutting g machi machine. ne. The edges edges of all all plates plates shall shall be perfe perfectl ctly y straig straight ht and unifor uniform m throughout. #ut edges shall be -isually e5amined for laminations laminations and inclusions. ll corners shall be shaped so as to be notch free, sheared or cropped edges shall be dressed so that they are free from distortion and burrs. "dge preparations for field welding shall be done in the shop 4.3.4 C9tting o !eav) "e;tion: The rele-ant standard standard rolled rolled shapes shapes or plates plates thic'ness thic'ness e5ceeding e5ceeding +0 mm before before cutting cutting pre7 0
heating 8in 66 #9 shall be used. ll cut edges shall be free of sharp notches and gauges. 4.2.4 "t&aig>tening
ll steel material shall be straight and free from bends or twists. $f the sections are distorted or twisted twisted during during transit, transit, storage storage etc. they shall be straight straightened ened andor flattened flattened by straighte straightening ning machine at ambient temperature, though minor bends may be corrected by limited heating under super-ision. Date : 15.07.2011 Revision : 02 Page : /13
4.2.+ Ben(ing The bending of plates and sections to specially required shapes shall be done on appropriate machine. 4.2.6 !o8es %unching and or drilling shall be done accurately as per the drawings and burrs remo-ed effecti-ely. :here se-eral parts are to be connected to -ery close tolerances, such parts shall be first assembled, tightly clamped together and drilled through. ll holes shall be minimum 1.+mm larger than the sie of the bolt. The holes shall be drilled reamed within the allowable limits specified in %roect specs. ;oles for bolts shall not be formed by a gas cutting process e5cept in special case with specific permission of the customer. 4.2.< Not;>es The ends of all oints, beams and girders shall be cut truly square unless required otherwise otherwise and oist flanges shall be neatly cut away or notched where necessary, the notches being 'ept as small as possible. 4.2.= Asse?<8) (tructures shall be assembled in igs or on suitable surfaces plates with proper layouts. The parts to be oined groo-e welds shall be brought into correct alignment. The members to be welded shall be held in the correct position by bolts, clamp and wedges where practicable. ny wedges used to space root gaps shall be remo-ed from the root gaps immediately after tac' welding and before ma'ing the root run. fter completion of oint fit7up, T! controlor will chec' the fit7up and he will release the oint for welding. The fabricated components shall be assembled in such a manner that they are neither twisted nor otherwise damaged. damaged. $n order to minimie distortion in a member the components shall be positioned by using clamps, clips, igs and other suitable manner and fasteners shall be placed in a balanced pattern. $f necessary items li'e roof trusses shall be trial assembled as per appro-ed assembly drawing 'eeping in -iew the actual site conditions prior to dispatch to site for erection, so that, they can be con-en con-enie ientl ntly y preass preassemb embled led before before erecti erection on.. *eces *ecessar sary y match match mar's mar's shall shall be made made on these these components before disassembly in the shop and dispatching.
Date : 15.07.2011 Revision : 02 Page : 7/13
4.2.> Bo8ting ll bolt and nuts shall be used as per appro-ed shop drawing drawing and contract specification. nchor nchor bolt and nuts shall be as per specification. 4.2.10
+e8(ing
:elding procedure qualifications and welders and welding operators performance qualification test shall be made in accordance with ?( "* $(/ or rele-ant (T (T standards. 4.2.10.1 (ge P&e'a&ation Ins'e;tion The edges or surfaces of parts to be oined by welding shall be uniform, smooth and cleaned from all foreign materials such as moisture, slag, oil, grease, paint, scale or rust. "dge preparation shall be -erified for proper groo-e angle and root face dimensions. :elding groo-e dimensions shall be inspe inspecte cted d as per shop shop drawi drawings ngs under under tac'7w tac'7weld elded ed condit condition ion prior prior to weldi welding. ng. The The allow allowabl able e misalignment of adoining plates to be butt7welded shall be in accordance with :( @1.1or ?(7"*7 $(/. 4.2.10.2 Fit9' Asse?<8) The embers embers or %lates %lates to be welde welded d are fit7up, fit7up, align aligned ed and retai retained ned in positi position on to weldi welding ng operations. operations. The location of integral parts members to t o be assembled shall be chec'ed dimensionally dimensionally prior to full welding. Tac' Tac' welds shall be use for secure alignment. )enerally, the tac' welds shall be subect to the same quality requirement as the final welds unless otherwise specified. Tac' welds containing any crac's shall be remo-ed thoroughly and replaced with sound tac' welds. (ie and location of tac' welds based on (pecification. (pecification. 4.2.10.3 Ba;=ing "t&i' Ins'e;tion ?ac'7stripped surfaces shall be -isually chec'ed for root gap prior to start welding. 4.2.10.4 +e8(ing P&o;ess •
•
The following practices shall be used for welding. •
un7on and run7off plates shall be welded at the ends of weld lines of crucial butt welds.
•
%rior to welding the surface to be welded and filler material to be used shall be chec'ed.
%rior to welding root opening, groo-e angle and the crucial dimensions dimensions shall be chec'ed and groo-e face shall be free from oil, water and dirt. •
%rior to welding the welding current shall be measured the most appropriate welding condition 8current A -oltage9 shall be maintained with ammeter and -oltmeter through out welding wor'.
•
ll welding is to be carried out out in an appro-ed en-ironment en-ironment and, and, if necessary, necessary, additional additional protection may be required. ll oints are to be dried before welding in damp climatic condition.
Date : 15.07.2011 Revision : 02 Page : /13
•
@uring welding wor', the most appropriate arc length, angle and welding speed shall be maintained so that welding defects shall be a-oided and arc energy requirements requirements are satisfied. &illet weld terminating terminating at the end of members shall be returned returned continuously around around the corner for
•
a distance of not less than twice the sie of the weld. (urfaces of butt oints required to be flush shall be finished so as not to reduce the thic'ness of the
•
inner base metal or weld metal than 1mm or +B of the thic'ness whiche-er is the smaller not lea-e reinforcement reinforcement that e5ceed 1mm. ll reinforcement reinforcement shall blend smoothly into the plate surfaces with transition areas free from undercut. •
#hipping and gouging shall be used, pro-ided grinding follows them. $n the case of multi layer welding, slags and spatters on each completed bead shall be remo-ed
•
prior to the start of welding for t he following layer. •
ll craters shall be filled to the full full cross section of the welds. welds.
4.2.10.4.1 T)'e o +e8(ing P&o;ess ll :elding :elding acti-ities shall shall be carried out out as per the appro-ed appro-ed :elding :elding procedure specification. specification. The following :elding %rocess used in &abrication wor's •
$) A ) %rocess
•
(: %rocess
•
&#: %rocess
•
(: %rocess
4.2.10.4.2 8e;t&o(es The electrodes used for welding shall be of suitable type and sie depending upon specifications of the parent materials, the method of welding, the position of welding and quality of welds desired. ;owe-er, only low hydrogen electrodes 8" <01=9 shall be used for plates and sections. ll low hydrogen electrodes shall be ba'ed and stored before use as per manufacturers recommendation. The electrodes shall be re7ba'ed at 2+0 C# to 300C # for one hour and later on cooled in the same o-en to 100C#. &rom ba'ing o-en the electrode shall be transferred to a holding o-en maintaine maintained d at 60C #D<0C #D<0C #. The electrodes electrodes shall be drawn drawn from this o-en for use. :here :here coated electrodes are used they shall meet the requirements of rele-ant ?(7"*7$(/ (tandard, ?are "lectrod "lectrode e and )ranular )ranular flu5 conform conform to rele-ant rele-ant ?(7"*7$(/ ?(7"*7$(/ (tandard. (tandard. :here :here #harpy #harpy E D *otch -alues are required on the base metal, an electrode meeting the requirement of ?(7"*7$(/ or :( 0
and ha-ing a minimum a-erage #harpy E7 notch impact strength of 2+ ft, lbs at D20 c. Date : 15.07.2011 Revision : 02 Page : /13
4.2.10.4.3 P&e>eat an( Inte&'ass Te?'e&at9&e %reheating of abo-e 6+ degree # shall be applied for o-er 3=mm thic' of (3++F, F/, F2 and !2 steel plate by means of o5y7 acetylene flame or non7carboniing li'e G%). Hniform heating of the surface e5tending up to a distance of three times the thic'ness of the plate on either side of the plate shall be obtained. %reheating minimum 1<< degree # shall be applied for rele-ant ?(7"*7$(/ (tandard rolled shapes or plates equal or grater than +0mm in thic'ness oined by partial or full penetration welds in tension The specified preheat temperature and minimum inter7pass temperature shall be maintained during welding progress. Thermo7chal' or other appro-ed methods shall be used for measuring the plate temperature. 4.2.10.4.4 "e@9en;e o +e8(ing 4Cont&o8 o Disto&tion an( ">&in=age •
The sequence of welding shall be selected to ensure that the components assembled by welding are free from distortion and large residual stresses are not de-eloped
•
$n assembling and oining parts of a structure or of built D up members and in welding reinforcing parts to members, the procedure and sequence shall be such as will minimie distortion and shrin'age.
•
$n so far as practicable, all welds shall be deposited in symmetrical sequence so that shrin'age on both sides of the structure will be equalied.
•
Foints e5pected to ha-e significant shrin'age shall be welded before oints e5pected to ha-e lesser shrin'age and with as little restraint as possible.
•
ll shop splices in each component part of a co-er plate beam or built D up members shall be made before such component part is welded to other components parts of the member.
•
ll welding shall be carried out continuously to completion or to a point that will ensure freedom from crac'ing before the oints is allowed to cool below the minimum specified preheat and inter7 pass temperature.
•
?utt weld in flange plates and or web plates shall be completed before the flanges and webs are welded together.
•
The ends of butt welds shall ha-e full throat throat thic'ness. This shall be obtained obtained on all main butt welds by the use of run off and run on pieces adequately secured on either side of main plates. dditional metal remaining after the remo-al of e5tension pieces shall be remo-ed by grinding or by gas cutting. 4.2.10.4.+ 6is9a8 a?ination o +e8(s "ach reinforcement height for butt welds and leg dimensions for fillet welds shall be chec'ed in addition to bead contour appearance. lso, possible presence of such ser-ice defects, undercut, Date : 15.07.2011 Revision : 02 Page : 10/13
crac', surface porosity etc. shall be chec'ed -isually. The reinforcement reinforcement on each side of butt7welded oints shall be be chec'ed in accordance accordance with :( :( @ 1.1 or ?(7"*7$(/ ?(7"*7$(/
Temporary lugs, braces and clips shall be welded in connection with :%( and these shall be remo-ed without damaging the base metal and the area ground flash and smooth. 4.2.11 PROCD%R FOR B%I*T %P $IRDR" / BAM" ,.2.11 ,.2.11.1 .1 P&e'a&at P&e'a&ation ion o Mate&ia8 Mate&ia8
ar'ing of steel shall be done in accordance with the shop drawings and cutting plan. aterial cutting shall be carried out by gas. "ither by pug cutting or #*# machine to cut the plates to the required sies. The dimensions and shape of the edges to be oined by welding shall be chec'ed as per appro-ed drawing specification. (urfaces and edge preparation shall be free from loose scale, slag, grease, paint and other foreign matter. "dge preparation shall be -erified for proper groo-e angle and root face dimensions. Foint surfaces shall be free from fins and tears. 4.2.11.2 Fit9' Asse?<8) ?uilt up )irder (tructure shall be assembled in igs or on suitable surfaces plates with proper layouts as per the @rawing. ?utt weld in flange plates and or web plates shall be completed before the flanges flanges with web fit7up ssembl ssembly. y. The &lange %lates shall be fit Dup with web plate, plate, for correct alignment and held in position by use suitable de-ices or by tac' welds until welding is completed to assure the most suitable welding position and accurate assembly. fter completion of &langes and :eb oint fit7up, T! #ontrolor shall be chec' the fit7up and release for welding.
4.2.11.3 +e8(ing P&o;ess :elding :elding shall be carried carried out as per the appro-ed appro-ed :elding :elding procedur procedure e specifica specification tion 8:%(9 and welders. un7on and run7off plates shall be welded at the ends of the )irder beam. 0
?efore welding start, oints shall be preheated abo-e 6+ c by means of gas flame to bring to the specified preheat preheat temperature in the full thic'ness of the base metal for a distance equal to the thic'ness of the part being welded. 8Thic'ness t I 3= mm9 specified preheat temperature and minimum inter7pass temperature shall be maintained during welding progress. The temperature shall be chec'ed by thermal chal'. The appro-ed electrodes shall be used for welding as per : %(. @uring welding most appropriate arc length, angle and welding speed shall be maintained so that welding defects shall be a-oided. $n the case of multi layer welding, slags and spatters on each completed bead shall be remo-ed prior to the start of welding for the following layer. fter fter completion of welding all Temporary Temporary lugs, un7on and run7off plates plates shall be remo-ed without without damaging the base metal and the the area ground flash and Date : 15.07.2011 Revision : 02 Page : 11/13
smooth. ll welding area shall be clean and inspect as per specification. fter completion of inspection and test for girder release for further fabrication acti-ities.
,.2.12 NOND"TR%CTI6 T"TIN$ 4NDT:
ll non7destructi-e non7destructi-e testing shall shall be performed as as per appro-ed agency agency as per the contract in accordance with the requirements of the applicable standards and proect specifications. specifications. *on7destructi-e Testing shall be performed as follows
(l.*o.
@escription
*@T TJ%"
Eisual $nspection
HT
T
%T
aw material plate 1
2
thic'ness +0 mm and abo-e &ull penetration butt
100B
K
K
K
100B
K
K
K
100B
K
K
K
100B
K
K
K
welds 3
%artial %enetration butt weld
4
ll fillet weld weld
K %roect (pecification third party $nspection agency shall be engaged as independent independent and appro-ed testing and inspection agency to carry out the HT and %T on :eldments. 8$f there is proect specification9 4.2.12.1 $ene&a8 Re@9i&e?ent O 6is9a8 Ins'e;tion :eld Eisual inspection shall be carried by &abrication "ngineers or certified :elding $nspector as per ?(7"*7$(/ standard for e5ternal defects li'e, surface porosity, under cut, e5cess penetration, o-er laps, lac' of penetration or incomplete fusion and fillet sies. 4.2.12.2 $ene&a8 Re@9i&e?ents O *i@9i( Penet&ant Testing Testing 4PT Giquid %enetrant Testing procedures shall be in accordance with (T " 16+ or rele-ant ?(7"*7 $(/ (tanda (tandard. rd.Thi This s test test shall shall be carrie carried d durin during g the weldi welding ng proces process s while while bac' bac' gougin gouging. g. The e-aluation of indications and the acceptance criteria shall be in accordance with (ec.E$$ @i-.1 (" (" code or rele-ant "*7$(/ standards. Date : 15.07.2011 Revision : 02 Page : 12/13
4.2.12.3 $ene&a8 &e@9i&e?ents o Magneti; Pa&ti;8e Testing 4MT agnetic particle Testing procedures shall be in accordance with (T " <0>, :( @ 1.1 or rele-ant ?(7"*7$(/ (tandard. The e-aluation of indications and the acceptance criteria shall be in accordance with (T " <0>, :( @ 1.1 or rele-ant ?(7"*7$(/ (tandard . $ndependent testing authority %$ reports shall be obtained for fillet welds.
4.2.12.4 $ene&a8 Re@9i&e?ents O %8t&asoni; a?ination 4%T: The ultrasonic Testing of plates for lamination shall be in accordance with ( 43+ and HT of ?utt oint shall be in accordance with (T " 164, :( @ 1.1 or rele-ant ?(7"*7$(/ (tandard. $ndependent $ndependent testing authority authority HT reports reports shall be obtained obtained for all butt oints. +. DIMN"IONA* IN"PCTION The fabricated steel structure shall be inspected in accordance with respecti-e appro-ed fabrication drawi drawing ngs s and specif specifica icatio tion. n. /-er /-er all lengt length, h, orien orientati tation on,, diago diagonal nal measur measureme ement nt and and all all other other dimensions dimensions shall be -erified and recorded. $f dimensions dimensions are not with required tolerance the member shall be corrected prior to further process. ll dimensions shall be recorded in appro-ed format. 100B -isual inspection shall be carried out for e5ternal defects. T! uality staffs shall conduct the final inspection and re-iew all inspection reports and prepared as inspection and test plan 8$T%9. 6. PROTCTION .1
"!OT "!OT B*A" B*A"TIN TIN$ $ 4"9& 4"9&a;e a;e P&e'a& P&e'a&ati ation on
brasi-es for blast cleaning shall be clean, dry and free of any constituent. (ilica sand shall not be used. (urface preparation shall be in accordance with $(/ =+01701 and technical data sheet of specified paint. brasi-e shall be of steel grit and shot in the ratio of <0B 7 30B. The surface grade finish shall be (a 2 L or as recommended by manufacturer. manufacturer. (urface profile shall not be less t han 1+ microns and more than 1+0 microns, since too low height, pre-ents proper adhesion and too high profile may lead to profile pea's protruding the coating resulting in early pinpoint rusting. %aint shall be applied to dry, clean prepared surfaces under controlled fa-ourable weather conditions and in accordance with manufacturer data sheet. 6.2
Painting A''8i;ation
%ainting shall be applied as per the proect specification. @ry film thic'ness shall be chec'ed prior to shipment to proect site and painting inspection report shall be maintained. %reparation generally shall comply with requirements ((%# and printed instructions of the manufacturer. #hec' that all Date : 15.07.2011 Revision : 02 Page : 13/13
coating materials to be used are recommended by the manufacturers for the particular surface and condition of e5posure. %ainting shall be carried out with s'illed wor'ers. ll coating materials shall be applied e-enly in a continuous full coat free from o-er7spray, dry7spray, wrin'ling, sagging, curtaining, holidays, holidays, thin spot, pinholes and other film defects. <. PAC#IN$ AND D*I6R-
The The pain painte ted d stru struct ctur ures es afte afterr fabr fabric icat atio ion n shal shalll be prot protec ecte ted d from from furt furthe herr dama damage ge duri during ng transportation. The materials will be loaded on to the trailers using timber supports and separators and secured properly to pre-ent any damage to the material while transportation to site. &abricated items will be deli-ered loose. inor fabricated items, which are not li'ely to be subect to permanent deformation during handling operations operations 8i.e. bracing etc9 maybe bundled or hoped. (mall items 8i.e. bolts, loose, cleats etc9 will be pac'ed in cratesdrums or loaded on pallets. =. IN"PCTION AND T"T P*AN ppro-ed $nspection $nspection and test plan shall be implemented implemented during each and e-ery e-ery stage of fabrication, to ensure the wor' is carried out with f ull compliance drawings drawings and specification. The $nspection and appro-ing parties as per $T% shall ensure the quality of wor' at e-ery le-el.
