146625065 6 Welding Symbols Weld Preparations

8/20/2019 146625065 6 Welding Symbols Weld Preparations

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Copyright © 2004, TWI Ltd World Centre for Materials Joining

Joints may be indicated: Joints may be indicated:

- by detailed setches, sho!ing e"ery- by detailed setches, sho!ing e"ery

dimensiondimension

- by symbolic- by symbolic

representationrepresentation

Weld sy'(ols on dra)ingsWeld sy'(ols on dra)ings


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# method o$ trans$erring in$ormation $rom# method o$ trans$erring in$ormation $rom

the design o%ce to the !orshop is:the design o%ce to the !orshop is:

The abo"e in$ormation does not tell &s m&chThe abo"e in$ormation does not tell &s m&chabo&t the !ishes o$ the designer' We ob"io&slyabo&t the !ishes o$ the designer' We ob"io&sly

need some sort o$ code !hich !o&ld beneed some sort o$ code !hich !o&ld be

&nderstood by e"eryone'&nderstood by e"eryone'

(ost co&ntries ha"e their o!n standards $or(ost co&ntries ha"e their o!n standards $orsymbols'symbols'

)ome o$ them are *) 4++ art 2, #W) #2'4 )ome o$ them are *) 4++ art 2, #W) #2'4

*) ./ 221 I)3 21*) ./ 221 I)3 21

Please weldPlease weld

herehere



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#d"antages o$ symbolic representation:#d"antages o$ symbolic representation:


5isad"antages o$ symbolic representation:5isad"antages o$ symbolic representation:

• simple and 6&ic plotting on the dra!ingsimple and 6&ic plotting on the dra!ing

• does not o"er-b&rden the dra!ingdoes not o"er-b&rden the dra!ing

• no need $or additional "ie!no need $or additional "ie!

•gi"es all necessary indications regarding thegi"es all necessary indications regarding thespeci7c 8oint to be obtainedspeci7c 8oint to be obtained

• &sed only $or &s&al 8oints&sed only $or &s&al 8oints

• re6&ires training $or properlyre6&ires training $or properly

&nderstanding o$ symbols&nderstanding o$ symbols


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9s&ally, the symbolic representation9s&ally, the symbolic representation

incl&des:incl&des:


The elementary symbol may beThe elementary symbol may be

completed by:completed by:

• an arro! linean arro! line

• a re$erence linea re$erence line

• an elementary symbolan elementary symbol

• a s&pplementary symbola s&pplementary symbol

• a means o$ sho!ing dimensionsa means o$ sho!ing dimensions

• some complementary indicationssome complementary indications


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Weld ele'entary sy'(ols

ario&s categories o$ 8oints areario&s categories o$ 8oints arecharacterised by an elementary symbol'characterised by an elementary symbol'

This symbol is similar to the shape o$ theThis symbol is similar to the shape o$ the

!eld to be made'!eld to be made'

)6&are b&tt !eld)6&are b&tt !eld

Weld typeWeld type )etch)etch )ymbol)ymbol

)ingle b&tt !eld)ingle b&tt !eld


7/54Copyright © 2004, TWI Ltd World Centre for Materials Joining


)ingle- b&tt)ingle- b&tt

!eld !ith broad!eld !ith broad

root $aceroot $ace


)ingle be"el)ingle be"el

b&tt !eldb&tt !eld

)ingle be"el)ingle be"el

b&tt !eld !ithb&tt !eld !ithbroad root $acebroad root $ace

*acing r&n*acing r&n




)ingle-9)ingle-9

b&tt !eldb&tt !eld


)ingle-J)ingle-Jb&tt !eldb&tt !eld

;illet !eld;illet !eld

)&r$acing)&r$acing



Con"ention o$ the arro! line *) ./ Con"ention o$ the arro! line *) ./ #W):#W):

%rro) line

aa )hall)hall to&ch the 8oint intersectionto&ch the 8oint intersection

bb )hall)hall not be parallel to the dra!ingnot be parallel to the dra!ing cc)hall)hall point to!ards a single platepoint to!ards a single plate

preparation !hen only one plate haspreparation !hen only one plate has

preparationpreparation



Con"ention o$ the re$erence line #W)Con"ention o$ the re$erence line #W)# 2'4# 2'4

&eference line

aa )hall)hall to&ch the arro! lineto&ch the arro! line

bb )hall)hall be parallel to the bottom o$ thebe parallel to the bottom o$ thedra!ingdra!ing



Con"ention o$ the re$erenceCon"ention o$ the re$erenceline *) ./ I)3 221:line *) ./ I)3 221:

oorr

&eference line

aa )hall)hall to&ch the arro! lineto&ch the arro! line

bb )hall)hall be parallel to the bottom o$ thebe parallel to the bottom o$ the

dra!ingdra!ing

cc There shallThere shall be a $&rther broen linebe a $&rther broen line

abo"e or beneath the re$erence line /otabo"e or beneath the re$erence line /ot

necessary !here the !eld is symmetrical



Welds =Welds =on arro! side>on arro! side> o$ 8oint goo$ 8oint go &nderneath&nderneath the re$erence line !hilethe re$erence line !hile !elds =!elds =the other side>the other side> o$ the 8oint, goo$ the 8oint, go on topon top o$ the re$erence lineo$ the re$erence line

)ymbols !ith a)ymbols !ith a "ertical line"ertical line component m&st becomponent m&st be

dra!n !ith the "ertical line to thedra!n !ith the "ertical line to the le$t sidele$t side o$o$

the symbolthe symbol

#ll#ll C)#C)# dimensions are sho!n to thedimensions are sho!n to the le$tle$t o$ theo$ the

symbolsymbol

#ll#ll linearlinear dimensions are sho!n on thedimensions are sho!n on the rightright o$o$the symbol i'e' n&mber o$ !elds, length o$the symbol i'e' n&mber o$ !elds, length o$

!elds, length o$ any spaces!elds, length o$ any spaces

Incl&ded angle and root opening are sho!n onIncl&ded angle and root opening are sho!n on

toptop o$ the symbolo$ the symbol

%WS % *.+ r,les



1010 3 x 50 (70)3 x 50 (70)

%WS % *.+ r,les-ea'/le

1010

5050

7070



WeldsWelds this sidethis side o$ 8oint, go on theo$ 8oint, go on the &nbroen&nbroen

re$erence line !hilere$erence line !hile !elds!elds the other sidethe other side o$ theo$ the 8oint, go on the 8oint, go on the broenbroen re$erence linere$erence line

)ymbols !ith a)ymbols !ith a "ertical line"ertical line component m&st becomponent m&st be

dra!n !ith the "ertical line to thedra!n !ith the "ertical line to the le$tle$t side o$side o$

the symbolthe symbol

#ll#ll C)#C)# dimensions are sho!n to thedimensions are sho!n to the le$tle$t o$ theo$ the

symbolsymbol

#ll#ll linearlinear dimensions are sho!n on thedimensions are sho!n on the rightright o$o$the symbol i'e' n&mber o$ !elds, length o$the symbol i'e' n&mber o$ !elds, length o$

!elds, length o$ any spaces!elds, length o$ any spaces

Incl&ded angle and root opening are sho!n onIncl&ded angle and root opening are sho!n on

toptop o$ the symbolo$ the symbol

$S E **553 r,les$S E **553 r,les



z 10z 10 3 x 503 x 50

(50)(50)

$S E **553 r,les - ea'/le

1010

5050

5050

#ll leg lengths#ll leg lengths shallshall be preceded by ? andbe preceded by ? and

throat by a or s in case o$ deep penetrationthroat by a or s in case o$ deep penetration!elds!elds



88

88

55

5 x 85 x 8

88

;illet !eld dimensions according #W) #;illet !eld dimensions according #W) #2'42'4

0illet )elds0illet )elds

5 leg on5 leg on

verticalvertical

membermember



55

a 5 (z 8)a 5 (z 8)

88

;illet !eld dimensions according *) ./;illet !eld dimensions according *) ./221221

oror

88

z 8z 8oror

z 8z 8

a 5 (z 8)a 5 (z 8)

0illet )elds0illet )elds



Inter'ittent llet )elds

Chain intermittent 7llet !eldChain intermittent 7llet !eld

lengthlength

llpitchpitch

eeaa

??

aa n@len@leaa n@len@le

?? n@len@le?? n@len@le

oror

)ymbol to *) ./ 221)ymbol to *) ./ 221




Chain intermittent 7llet !eldChain intermittent 7llet !eld

lengthlength

llpitchpitch

ee

??

?? l - el - e?? l - el - e

)ymbol to #W) #2'4)ymbol to #W) #2'4


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)taggered intermittent 7llet !eld)taggered intermittent 7llet !eld

lengthlength

llpitchpitch

eeaa

??

aa n@ln@leeaa n@ln@l

ee

?? n@ln@lee?? n@ln@l

ee oror

)ymbol to *) ./ 221)ymbol to *) ./ 221


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)taggered intermittent 7llet !eld)taggered intermittent 7llet !eldlengthlength

llpitchpitch

ee

??

?? l - el - e?? l - el - e

)ymbol to #W) #2'4)ymbol to #W) #2'4

eA2eA2


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Conca"e orConca"e or

Con"eBCon"eB

)&pplementary !eld)&pplementary !eldsymbolssymbols

Toes to be gro&ndToes to be gro&nd

smoothly *) ./smoothly *) ./

onlyonly)ite Weld)ite Weld

Weld allWeld allro&ndro&nd

S,//le'entary sy'(olsS,//le'entary sy'(ols


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)&pplementary !eld)&pplementary !eldsymbolssymbols

ro&ndro&nd

D&shD&sh

111111

;&rther s&pplementary in$ormation, s&ch as;&rther s&pplementary in$ormation, s&ch as

W) n&mber, or /5T may be placed in theW) n&mber, or /5T may be placed in the

7sh tail7sh tail

S,//le'entary sy'(olsS,//le'entary sy'(ols

WeldingWelding

processprocess

n&merical *)n&merical *)././ MR MR

Eemo"ableEemo"able

bacingbacingstripstrip

ermanentermanent

bacingbacingstripstrip

MM


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;illet;illet!eld!eld

5o&ble5o&ble

5o&ble5o&blebe"elbe"el

5o&ble 95o&ble 9

5o&ble J5o&ble J

Eepresentation o$ !elds done $romEepresentation o$ !elds done $rom (oth(othsidessides o$ the 8oint intersection, to&ched byo$ the 8oint intersection, to&ched by

the arro! headthe arro! head

Do,(le side )eld sy'(olsDo,(le side )eld sy'(ols


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.Bample:.Bample:

rod&ce a dra!ing gi"ing symbols $or the !eldrod&ce a dra!ing gi"ing symbols $or the !eld

gi"en as sho!n belo! to the speci7cation #W)gi"en as sho!n belo! to the speci7cation #W)

#2'4#2'4

Weld 5ra!ingWeld 5ra!ing

)ymbol)ymbol

5ra!ing5ra!ing

((((##



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.Bample:.Bample:

5ra! the symbols $or the !eld gi"en as5ra! the symbols $or the !eld gi"en as

sho!n belo! to the speci7cation *) ./sho!n belo! to the speci7cation *) ./

221221

Weld dra!ingWeld dra!ing

)ymbol)ymbol

5ra!ing5ra!ing111111

Weld sy'(ols on dra)ings

((((##


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1010

2020

3030

3535

1515

77

)t&dent symbols eBercise)t&dent symbols eBerciseComplete a symbols dra!ing $or the !eldedComplete a symbols dra!ing $or the !elded

8oint gi"en belo! to #W) #2'4 *) ./ 8oint gi"en belo! to #W) #2'4 *) ./

221221

#ll 7llet !eld leg lengths are F0 mm#ll 7llet !eld leg lengths are F0 mm



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)ol&tion #W))ol&tion #W)#2'4#2'4

F0F0

1010

2020

F0F0

F0F0

11

FF

F0F0



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)ol&tion *) ./)ol&tion *) ./221221 ??F0F0s 10s 10

s 20s 20 ??

F0F0

a G ?a G ?

F0F0s 1s 1

s Fs F

? F0? F0



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This has ma8or eHects on economics andThis has ma8or eHects on economics and

distortion control


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Weld /re/aration

Weld preparation depend on:Weld preparation depend on:

•!elding process!elding process

•preparation method a"ailablepreparation method a"ailable

•accessaccess

•type o$ 8ointtype o$ 8oint

•type o$ parent materialtype o$ parent material

•thicnessthicness

•!elding position!elding position

•in-ser"ice type o$ loadingin-ser"ice type o$ loading

Weld preparation $or arc !elding - see *) ./Weld preparation $or arc !elding - see *) ./

2++2


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Weld /re/aration

Welding process impacts &pon !eld preparationWelding process impacts &pon !eld preparation

#rc#rc

!elding!elding.*.*

WW


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Weld /re/aration

Welding process impacts &pon !eld preparationWelding process impacts &pon !eld preparation

((#((# (#(#

high heat inp&t process allo! a larger root $ace, lesshigh heat inp&t process allo! a larger root $ace, less!eld metal re6&ired, less distortions, higher!eld metal re6&ired, less distortions, higher

prod&cti"ityprod&cti"ity

i$ gap is too big ris o$ possible b&rn-thro&ghi$ gap is too big ris o$ possible b&rn-thro&gh

i$ gap is too small ris o$ lac o$ penetrationi$ gap is too small ris o$ lac o$ penetration


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Weld /re/aration

reparation method impacts &pon !eldreparation method impacts &pon !eld


Ee6&ires machining slo!Ee6&ires machining slo!

and eBpensi"eand eBpensi"e

Tight tolerance easier set-Tight tolerance easier set-

&p&p

Can be DameAplasma c&tCan be DameAplasma c&t

$ast and cheap$ast and cheap

Large tolerance set-&p canLarge tolerance set-&p can

be di%c&ltbe di%c&lt


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Weld /re/aration



ariations inariations in

c&tting linec&tting line

Eoot $ace too large lacEoot $ace too large lac

o$ penetrationo$ penetration

Eoot $ace too small b&rn-Eoot $ace too small b&rn-

thro&ghthro&gh

ariations inariations in

c&tting anglec&tting angle

Incl&ded angle too largeIncl&ded angle too large

hea"y distortions,hea"y distortions,

increase amo&nt o$ 7llerincrease amo&nt o$ 7llermetal re6&iredmetal re6&ired

Incl&ded angle too smallIncl&ded angle too small

lac o$ penetration, laclac o$ penetration, lac

o$ side !all $&siono$ side !all $&sion


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Weld /re/aration


preparation - correcti"e meas&respreparation - correcti"e meas&res

*acing strip mm*acing strip mm

or more, sameor more, same

materialmaterial

/o root/o root$ace$ace

Eoot $ace tooEoot $ace too

largelarge

Eec&t groo"e preparationEec&t groo"e preparation

Increase root gap andIncrease root gap and

&se bacing strip&se bacing strip


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Weld /re/aration


preparation - correcti"e meas&respreparation - correcti"e meas&res

Too bigAtooToo bigAtoo

small incl&dedsmall incl&ded

angleangle

Eec&t groo"e preparationEec&t groo"e preparation

Increase root gap andIncrease root gap and

&se bacing strip&se bacing strip

Warning< *acing strips gi"e a b&ilt-in cre"iceWarning< *acing strips gi"e a b&ilt-in cre"ice

•s&sceptible to corrosions&sceptible to corrosion

•gi"e a lo!er $atig&e li$egi"e a lo!er $atig&e li$e


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Weld /re/arations

#ccess impacts &pon !eld preparation#ccess impacts &pon !eld preparation


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Weld /re/arations



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Weld /re/arations


ipe !eld preparation - one side access only


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Weld /re/arations

Type o$ 8oint impacts &pon !eld preparationType o$ 8oint impacts &pon !eld preparation

•danger o$ b&rn-danger o$ b&rn-

thro&ghthro&gh

•di%c&lt to set-&pdi%c&lt to set-&p

•easy set-&peasy set-&p

•no b&rn-no b&rn-

thro&ghthro&gh

•corner 8oints re6&ire oHsetcorner 8oints re6&ire oHset

oHseoHse

tt


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Weld /re/arations

Type o$ 8oint impacts &pon !eld preparationType o$ 8oint impacts &pon !eld preparation

*e"el angle 10K*e"el angle 10K

Incl&ded angle Incl&ded angle

0K0K

Incl&ded angle Incl&ded angle

*e"el angle 0K*e"el angle 0K

•lap and s6&are edge b&tt 8oints do notlap and s6&are edge b&tt 8oints do notre6&ire preparationre6&ire preparation

ld i


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Weld /re/arations

Type o$ parent material impacts &pon !eldType o$ parent material impacts &pon !eld


)teel)teel #l&mini&m#l&mini&m

•to red&ce distortions on stainless steelsto red&ce distortions on stainless steels

!elds, red&ce incl&ded angle and increase root!elds, red&ce incl&ded angle and increase root

$ace$ace

•to a"oid lac o$ side !all $&sion problemsto a"oid lac o$ side !all $&sion problems

al&mini&m re6&ire larger incl&ded angles thanal&mini&m re6&ire larger incl&ded angles than

steelsteel0K0K

10K10K

G0-+0KG0-+0K

1-4K1-4K

ld i


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Weld /re/arations

Thicness o$ parent material impacts &ponThicness o$ parent material impacts &pon

!eld preparation!eld preparation•a single be"el groo"e re6&ires a "ol&me o$a single be"el groo"e re6&ires a "ol&me o$

!eld metal proportional to the s6&are o$ plate!eld metal proportional to the s6&are o$ plate

thicnessthicness

•its lac o$ symmetry lead to distortionsits lac o$ symmetry lead to distortions

Eed&ce shrinage by:Eed&ce shrinage by:

•red&ce !eld "ol&mered&ce !eld "ol&me

•&se single pass !elding&se single pass !elding

W ld i


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Weld /re/arations

Eed&ce !eld "ol&me by:Eed&ce !eld "ol&me by:

•red&ce incl&ded anglered&ce incl&ded angle


!eld preparation!eld preparation

•red&ce root gapred&ce root gap

W ld ti


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Weld /re/arations


•increase root $aceincrease root $ace



•&se do&ble be"el !eld prep&se do&ble be"el !eld prep

W ld ti


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Weld /re/arations


•&se 9 prep instead prep&se 9 prep instead prep



9 prep better than 9 prep better than

prepprep prep better than 9 prep better than 9

prepprep

W ld ti


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Weld /re/arations

Eed&ce distortions by &sing an asymmetric Eed&ce distortions by &sing an asymmetric

prep instead o$ a symmetric prepprep instead o$ a symmetric prep



tA1tA1

tt

•!eld 7rst into deeper side!eld 7rst into deeper side

•a$ter !elding hal$ o$ depth, root baca$ter !elding hal$ o$ depth, root bac

go&ginggo&ging

•!eld completely on bacside!eld completely on bacside

•

W ld ti


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Weld /re/aration

; symmetric; symmetric


Welding position impacts &pon !eldWelding position impacts &pon !eld


C asymmetricC asymmetricpreparationpreparation

I$ symmetric preparation is &sed in the CI$ symmetric preparation is &sed in the C

position the !eld may spill o&t o$ the groo"eposition the !eld may spill o&t o$ the groo"e

0K0K

10K10K 0K0K

FKFK

W ld ti


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Weld /re/aration

Type o$ loading impacts &pon !eld preparationType o$ loading impacts &pon !eld preparation

)tatic loads - prohibited application o$ one)tatic loads - prohibited application o$ one

sided 7llet !eldsided 7llet !eld

W ld ti


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Weld /re/aration


)tatic loads - e6&al throat T 8oints)tatic loads - e6&al throat T 8oints

F1 mmF1 mm

!eld area F0!eld area F0mmmm22

!eld area +0!eld area +0mmmm22

F1 mmF1 mm

•no preparation re6&iredno preparation re6&ired

•danger o$ lamellardanger o$ lamellar

tearingtearing

•preparation re6&iredpreparation re6&ired

•red&ced distortionsred&ced distortions

00

KK

W ld ti


53/54


Weld /re/aration


)tatic loads - e6&al throat T beams in bending)tatic loads - e6&al throat T beams in bending

ne&trane&tra

l aBisl aBis

deepdeep

penetrationpenetration

7llet !elds7llet !elds

normal 7lletnormal 7llet

!elds!elds

ne&trane&tra

l aBisl aBis

Lo!er ne&tral aBis is more ad"antageo&sLo!er ne&tral aBis is more ad"antageo&s

also helps to red&ce resid&al distortions


54/54

Weld /re/aration


5ynamic loads - $&ll "s' partial penetration5ynamic loads - $&ll "s' partial penetration

!elds!elds

do&ble be"eldo&ble be"el

!eld!eld 7llet !elds7llet !elds

Lac o$ penetration promotes cracing

Documents

146625065 6 Welding Symbols Weld Preparations