Miller Guide for Gmaw New

8/10/2019 Miller Guide for Gmaw New

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154 557 A

200702

Processes

MIG (GMAW) Welding

Guidelines ForGas Metal Arc

Welding (GMAW)

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2/26

4-1. E!essi"e #$atter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

1%

4-2. &orosit' . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

1%

4-. In!o$lete *usion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

1+

4-4. E!essi"e &enetration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

1+

4-%. ,a! / &enetration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

1+

4-+. urn roug . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

17

4-7. Wa"iness / ead . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

17

4-3. istortion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17

TAB! "F #"$T!$T%

%!#T&"$ 1 %AF!T' P!#AT&"$% * !A+ B!F"! %&$G . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1

1-1. #'bol 5sage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1

1-2. Ar! Welding 6aards . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1

1-. Additional #'bols *or Installation8 $eration8 AndMaintenan!e

. . . . . . . . . . . . . . . . . . . . . . . . . . . . .

1-4. 9ali/ornia &ro$osition +% Warnings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

1-%. &rin!i$al #a/et'#tandards

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4

1-+. EM* In/oration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4

%!#T&"$ , GA% M!TA A# W!+&$G (GMAW) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

2-1. '$i!al GMAW #eiautoati! #etu$ Wit 9onstant #$eed*eeder

2-2. '$i!al GMAW #eiautoati! #etu$ Wit Voltage-#ensing*eeder

. . . . . . . . . . . . . . . . . . . . . . . . . . .+

. . . . . . . . . . . . . . . . . . . . . . . . . . .7

2-. '$i!al GMAW &ro!ess 9ontrol #ettings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3

2-4. 6olding And &ositioning Welding

Gun. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

:

2-%. 9onditions at A//e!t Weld ead#a$e

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10

2-+. Gun Mo"eent uringWelding

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .11

2-7. &oor Weld ead 9ara!teristi!s . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .11

2-3. Good Weld ead 9ara!teristi!s . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .12

2-:. 9oon GMAW #ielding Gases . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .12

%!#T&"$ - M"+!% "F GMAW TA$%F! . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-

-1. #ort 9ir!uit rans/er . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1

-2. Globular rans/er . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .14

-. #$ra' Ar! rans/er . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .14

%!#T&"$ 4 GMAW W!+&$G T"B!%""T&$G . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15


3/26

%!#T&"$ 1 %AF!T' P!#AT&"$% * !A+ B!F"! %&$G

A Warning/ Protect 0oursel and ot2ers rom in3ur0 read and ollow t2eserecautions.

so ;oining s'bols.

A Mars a secial saet0message.

o Means Note; not safety

related.

1*,. Arc Welding a8ards

A T2e s0m6ols s2own 6elow are used t2roug2out t2is manualto call attention to and identi0 ossi6le 2a8ards. W2en 0ousee t2e s0m6ol9 watc2 out9 and ollow t2e relatedinstructions to a:oid t2e 2a8ard. T2e saet0 inormationgi:en 6elow is onl0 a summar0 o t2e more comlete saet0inormation ound in t2e %aet0 %tandards listed in %ection

1*5. ead and ollow all %aet0 %tandards.A "nl0 ;ualiied ersons s2ould install9 oerate9 maintain9

and reair t2is unit.

A +uring oeration9 ee e:er06od09 eseciall0 c2ildren9awa0.

!!#T %"#< can ill.

ou!ing li"e ele!tri!al $arts !an !ause /atalso!s or se"ere burns. e ele!trode and wor!ir!uit is ele!tri!all' li"e wene"er te out$ut is on.e in$ut $ower !ir!uit and a!ine internal!ir!uits are also

li"e wen $ower is on. In seiautoati! or autoati! wire welding8te wire8 wire reel8 dri"e roll ousing8 and all etal $arts tou!ingte welding wire are ele!tri!all' li"e. In!orre!tl' installed ori$ro$erl'

grounded e?ui$ent is aaard.

o not tou! li"e ele!tri!al$arts.

Wear dr'8 ole-/ree insulating glo"es and bod'$rote!tion.

Insulate 'oursel/ /ro wor and ground using dr' insulatingats or !o"ers big enoug to $re"ent an' $'si!al !onta!t witte wor or ground.

o not use A9 out$ut in da$ areas8 i/ o"eent is !on/ined8or i/ tere is a danger o/ /alling.

5se A9 out$ut @, i/ re?uired /or te welding $ro!ess.

I/ A9 out$ut is re?uired8 use reote out$ut !ontrol i/ $resenton unit.

Additional sa/et' $re!autions are re?uired wen an' o/te /ollowing ele!tri!all' aardous !onditions are$resentB in da$ lo!ations or wile wearing wet !lotingC onetal stru!tures su! as /loors8 gratings8 or s!a//oldsC wen in!ra$ed $ositions su! as sitting8 neeling8 or l'ingC or wentere is a ig ris o/ una"oid- able or a!!idental !onta!t witte wor$ie!e or ground. *or tese !onditions8 use te /ollowinge?ui$ent in order $resentedB 1) a seiautoati! 9 !onstant"oltage (wire) welder8 2) a 9 anual (sti!) welder8 or ) an

A9 welder wit redu!ed o$en-!ir!uit "oltage. In ostsituations8 use o/ a 98 !onstant "oltage wire welder isre!oended. And8 do not wor alone=

is!onne!t in$ut $ower or sto$ engine be/ore installing orser"i!ing tis e?ui$ent. ,o!out


4/26

is grou$ o/ s'bols eans Warning= Wat! ut=$ossible E,E9DI9 #69F8 MVI@G &AD#8 and 6&AD# aards. 9onsult s'bols and related instru!tions below/or ne!essar' a!tions to a"oid te aards.

urn o// all e?ui$ent wen not in use.

o not use worn8 daaged8 undersied8 or $oorl' s$li!ed !ables.

o not dra$e !ables o"er 'our bod'.

I/ eart grounding o/ te wor$ie!e is re?uired8 ground it

dire!tl' wit a se$arate !able. o not tou! ele!trode i/ 'ou are in !onta!t wit te wor8

ground8 or anoter ele!trode /ro a di//erent a!ine.

o not tou! ele!trode olders !onne!ted to two welding a-!ines at te sae tie sin!e double o$en-!ir!uit "oltage willbe $resent.

5se onl' well-aintained e?ui$ent. De$air or re$la!edaaged $arts at on!e. Maintain unit a!!ording to anual.

Wear a sa/et' arness i/ woring abo"e /loor le"el.

Fee$ all $anels and !o"ers se!urel' in $la!e.

9la$ wor !able wit good etal-to-etal !onta!t towor$ie!e or wortable as near te weld as $ra!ti!al.

Insulate wor !la$ wen not !onne!ted to wor$ie!e to$re"ent !onta!t wit an' etal ob>e!t.

o not !onne!t ore tan one ele!trode or wor !able to an'

single weld out$ut terinal.

%&G$&FA$T +# ="TAG! e>ists in in:erter*t0e welding ower sources ater remo:al o

inut ower. urn // in"erter8 dis!onne!t in$ut $ower8 and dis!arge in$ut

!a$a!itors a!!ording to instru!tions in Maintenan!e#e!tion be/ore tou!ing an' $arts.

FM!% A$+ GA%!% can 6e2a8ardous.

Welding $rodu!es /ues and gases. reatingtese /ues and gases !an be aardous to 'ourealt.

Fee$ 'our ead out o/ te /ues. o not breate te /ues.

I/ inside8 "entilate te area and


5/26

A# A'% can 6urn e0es and sin.

Ar! ra's /ro te welding $ro!ess $rodu!eintense "isible and in"isible (ultra"iolet andin/rared) ra's tat !an burn e'es and sin. #$ars/l o// /ro te

B&+P "F GA% can in3ure or ill.

#ut o// sielding gas su$$l' wen not in use.

Alwa's "entilate !on/ined s$a!es oruse a$$ro"ed air-su$$lied res$irator.

&a!eaer wearers ee$ awa'.

Wearers sould !onsult teir do!torbe/ore going near ar! welding8 gouging8

F'&$G M!TA can in3ure e0es.

Welding8 !i$$ing8 wire brusing8 andgrinding !ause s$ars and /l'ing etal. Aswelds !ool8 te' !an trow o// slag.

weld.

Wear an a$$ro"ed welding elet /itted wit a $ro$er sade o//il- ter lenses to $rote!t 'our /a!e and e'es wen welding orwat!ing (see A@#I 4:.1 and 37.1 listed in #a/et'#tandards).

Wear a$$ro"ed sa/et' glasses wit side sields under

'our elet. 5se $rote!ti"e s!reens or barriers to $rote!t oters /ro

/las8 glare and s$arsC warn oters not to wat! te ar!.

Wear $rote!ti"e !loting ade /ro durable8 /lae-resistantate- rial (leater8 ea"' !otton8 or wool) and /oot $rote!tion.

"T PAT% can cause se:ere 6urns.

o not tou! ot $arts bare anded.

Allow !ooling $eriod be/ore woring on gunor tor!.

o andle ot $arts8 use $ro$er toolsandlode i damaged.

#ielding gas !'linders !ontain gas underig $ressure. I/ daaged8 a !'linder !an e$lode.#in!e gas !'linders are norall' $art o/ tewelding $ro!ess8 be sure to treat te !are/ull'.

&rote!t !o$ressed gas !'linders /ro e!essi"e eat8

e!ani- !al so!s8 $'si!al daage8 slag8 o$en /laes8s$ars8 and ar!s.

Install !'linders in an u$rigt $osition b' se!uring to astationar' su$$ort or !'linder ra! to $re"ent /alling or ti$$ing.

Fee$ !'linders awa' /ro an' welding or oter ele!tri!al !ir!uits.

@e"er dra$e a welding tor! o"er a gas !'linder.

@e"er allow a welding ele!trode to tou! an' !'linder.

@e"er weld on a $ressuried !'linder e$losion will result.

5se onl' !orre!t sielding gas !'linders8 regulators8 oses8 and/it- tings designed /or te s$e!i/i! a$$li!ationC aintain teand asso!iated $arts in good !ondition.

urn /a!e awa' /ro "al"e outlet wen o$ening !'linder "al"e.

Fee$ $rote!ti"e !a$ in $la!e o"er "al"e e!e$t wen !'linder isin use or !onne!ted /or use.

5se te rigt e?ui$ent8 !orre!t $ro!edures8 and su//i!ientnu- ber o/ $ersons to li/t and o"e !'linders.

Dead and /ollow instru!tions on !o$ressed gas!'linders8 asso!iated e?ui$ent8 and 9o$ressed Gas

Asso!iation (9GA) $ubli!ation &-1 listed in #a/et' #tandards.


6/26


7/26

1*-. Additional %0m6ols For &nstallation9 "eration9 And Maintenance

F&! " !?P"%&"$ 2a8ard.

o not install or $la!e unit on8 o"er8 ornear !obustible sur/a!es.

o not install unit near /laables.

o not o"erload building wiring be sure $ower su$$l' s'steis $ro$erl' sied8 rated8 and $rote!ted to andle tis unit.

FA&$G $&T can cause in3ur0.

5se li/ting e'e to li/t unit onl'8 @running gear8 gas !'linders8 or an' otera!!essories.

5se e?ui$ent o/ ade?uate !a$a!it' to li/tand su$$ort unit.

I/ using li/t /ors to o"e unit8 be sure /orsare long enoug to etend be'ond o$$ositeside o/ unit.

M"=&$G PAT% can cause in3ur0.

Fee$ awa' /ro o"ing $arts su! as /ans.

Fee$ all doors8 $anels8 !o"ers8 andguards !losed and se!urel' in $la!e.

6a"e onl' ?uali/ied $ersons reo"edoors8 $anels8 !o"ers8 or guards /oraintenan!e as ne!essar'.

Deinstall doors8 $anels8 !o"ers8 orguards wen aintenan!e is /inised andbe/ore re- !onne!ting in$ut $ower.

!A+ &$%T#T&"$%.

Dead wners Manual be/ore using orser"i!- ing unit.

5se onl' genuine Miller


8/26

1%4 %%7 &age


9/26

1*5. Princial %aet0 %tandards

Safety in Welding, Cutting, and Allied Processes, A@#I #tandard4:.18 /ro Global Engineering o!uents ($oneB 1-377-41-%1348websiteBww w .global.is.!o).

Recommended Safe Practices for the Prearation for Welding andCut! ting of Containers and Piing8 Aeri!an Welding #o!iet'#tandard AW# *4.1 /ro Global Engineering o!uents($oneB1-377-41-%1348 websiteBww w .global. is.!o).

National "lectrical Code8 @*&A #tandard 708 /ro @ational *ire&rote!- tion Asso!iation8 &.. o :1018 1 atter' Mar! &ar8Huin!'8 MA022+::101 ($oneB +177700008 websiteBww w .n/$a.org).

Safe #andling of Comressed $ases in Cylinders8 9GA &a$let &-18 /ro 9o$ressed Gas Asso!iation8 17% e//erson a"is6igwa'8 #uite 10048 Arlington8 VA 222024102 ($oneB 704120:008 web- siteBww w .!ganet.!o).

Code for Safety in Welding and Cutting8 9#A #tandard W117.28/ro9anadian #tandards Asso!iation8 #tandards #ales8 173Dedale

oule"ard8 Dedale8 ntario8 9anada M:W 1D($oneB3004++727 or in oronto 41+74740448 websiteB ww w .!sain- ternational.org).

Practice %or &ccuational And "ducational "ye And %aceProtection,

A@#I #tandard 37.18 /ro Aeri!an @ational #tandards Institute811West 42nd #treet8 @ew or8 @ 100+3002 ($oneB 212+42

4:008 websiteBww w .ansi.org).

Standard for %ire Pre'ention (uring Welding, Cutting, and &ther#ot Wor)8 @*&A #tandard %18 /ro @ational *ire &rote!tion

Asso!iation8 &.. o :1018 1 atter' Mar! &ar8 Huin!'8 MA022+::101 ($oneB+177700008websiteBww w .n/$a.org).

#6A8 !!u$ational #a/et' and 6ealt #tandards /or GeneralIndus- tr'8 itle 2:8 9ode o/ *ederal Degulations (9*D)8 &art 1:108#ub$art H8 and &art 1:2+8 #ub$art 8 /ro 5.#. Go"ernent &rinting//i!e8 #u$er- intendent o/ o!uents8 &.. o 71:%48 &ittsburg8&A 1%2%0 (tere are 10 Degional //i!es$one /or Degion%8 9i!ago8 is12%22208websiteBww w .osa.go").

1*@. !MF &normation9onsiderations About Welding And e E//e!ts / ,ow *re?uen!'Ele!tri! And Magneti! *ields

Welding !urrent8 as it /lows troug welding !ables8 will !auseele!troagneti! /ields. ere as been and still is soe !on!ernabout su! /ields. 6owe"er8 a/ter eaining ore tan %00 studiess$anning 17 'ears o/ resear!8 a s$e!ial blue ribbon !oittee o/te @ational Desear! 9oun!il !on!luded tatB Je bod' o/e"iden!e8 in te !oittees >udgent8 as not deonstrated tate$osure to $ower- /re?uen!' ele!tri! and agneti! /ields is auan-ealt aard.K 6owe"er8 studies are still going /ort ande"iden!e !ontinues to be eained. 5ntil te /inal !on!lusions o/te resear! are rea!ed8 'ou a' wis to iniie 'our e$osureto ele!troagneti! /ields wen welding or !utting.

o redu!e agneti! /ields in te wor$la!e8 use te /ollowing$ro!eduresB

1. Fee$ !ables !lose togeter b' twisting or ta$ingte.

2. Arrange !ables to one side and awa' /ro teo$erator.

. o not !oil or dra$e !ables around 'ourbod'.

4. Fee$ welding $ower sour!e and !ables as /ar awa' /ro

o$erator as $ra!ti!al.

%. 9onne!t wor !la$ to wor$ie!e as !lose to te weld as

$ossible.

A6out Pacemaers/

&a!eaer wearers !onsult 'our do!tor be/ore welding or goingnear welding o$erations. I/ !leared b' 'our do!tor8 ten /ollowing teabo"e $ro!edures is re!oended.
http://www.global.ihs.com/http://www.global.ihs.com/http://www.global.ihs.com/http://www.nfpa.org/http://www.cganet.com/http://www.cganet.com/http://www.csa/http://www.ansi.org/http://www.ansi.org/http://www.nfpa.org/http://www.nfpa.org/http://www.osha.gov/http://www.osha.gov/http://www.global.ihs.com/http://www.global.ihs.com/http://www.nfpa.org/http://www.cganet.com/http://www.csa/http://www.ansi.org/http://www.nfpa.org/http://www.osha.gov/


10/26

1%4 %%7 &age 4


11/26

%!#T&"$ , GA% M!TA A# W!+&$G (GMAW)

Gas Metal Ar! Welding (GMAW) is a welding $ro!ess wi! >oins etals b' eating te etals to teir elting$oint wit an ele!tri! ar!. e ar! is between a !ontinuous8 !onsuable ele!trode wire and te etal beingwelded. e ar! is sielded /ro !ontainants in te atos$ere b' a sielding gas.

GMAW !an be done in tree di//erent wa'sB

#eiautoati! Welding - e?ui$ent !ontrols onl' te ele!trode wire /eeding. Mo"eent o/ welding gun is

!ontrolled b' and. is a' be !alled and-eld welding.

Ma!ine Welding - uses a gun tat is !onne!ted to a ani$ulator o/ soe ind (not and-eld). An o$erator asto !onstantl' set and ad>ust !ontrols tat o"e te ani$ulator.

Autoati! Welding - uses e?ui$ent wi! welds witout te !onstant ad>usting o/ !ontrols b' a welder oro$erator. n soe e?ui$ent8 autoati! sensing de"i!es !ontrol te !orre!t gun alignent in a weld >oint.

asi! e?ui$ent /or a t'$i!al GMAW seiautoati! setu$B

Welding &ower #our!e - $ro"ides welding $ower.

Wire *eeders (9onstant #$eed And Voltage-#ensing) - !ontrols su$$l' o/ wire to welding gun.

9onstant #$eed *eeder - 5sed onl' wit a !onstant "oltage (9V) $ower sour!e. is t'$e o/ /eeder as a

!ontrol !able tat will !onne!t to te $ower sour!e. e !ontrol !able su$$lies $ower to te /eeder and allows te!a$abilit' o/ reote "oltage !ontrol wit !ertain $ower sour!e


12/26

,*1. T0ical GMAW %emiautomatic %etu Wit2 #onstant %eed Feeder

1 9onstant Voltage(9V) Welding &ower#our!e

2 9onta!tor 9ontrol


13/26

,*,. T0ical GMAW %emiautomatic %etu Wit2 =oltage*%ensing Feeder

1 9onstant 9urrent (99-9)r 9ontstant Voltage (9V)Welding &ower #our!e

2 Weld 9able o *eeder

Ground 9able o Wor$ie!e

4 Wor$ie!e

% Voltage-#ensing 9la$

+ Welding Gun

7 Gun rigger De!e$ta!le

3 Voltage-#ensing Wire *eeder

: Gas 6ose

10 #ielding Gas 9'linder

1

10

2

:

3

7

4%

+

De/. 304 000-9

1%4 %%7 &age 7


14/26

,*-. T0ical GMAW Process #ontrol %ettings

11


15/26

,*4. olding And Positioning Welding Gun

o Welding +ire is energi2ed+hen gun trigger is ressed.3efore lo+ering helmet and

ressing trigger, -e sure +ireis no more than 456 in 47 mm/

ast end of

1no22le, and ti of +ire is osi!tioned correctly on seam.

1 6old Gun And 9ontrol Gunrigger

2 Wor$ie!e

2

Wor 9la$

4 Ele!trode Etension (#ti!out)1


16/26

,*5. #onditions T2at Aect Weld Bead %2ae

1

10

2

10

+

o Weld -ead shae deendson gun angle, direction oftra'el, electrode e8tensionstic)out/, tra'el seed,thic)ness of -ase metal, +irefeed seed +eld current/,and 'oltage.

Gun Angles And Weld Bead

Proiles

1 &us

2 &er$endi!ular

rag

!lectrode !>tensions (%ticout)

4 #ort

% @oral

+ ,ong

Fillet Weld !lectrode !>tension(%ticout)

7 #ort

3 @oral

: ,ong4 % Gun Tra:el %eed

10 #low

11 @oral

12 *ast

7 3 :

10 11 12

#-0+4-A

1%4 %%7 &age 10


17/26

,*@. Gun Mo:ement +uring Welding

o Normally, a single stringer-ead is satisfactory for mostnarro+ groo'e +eld oints.#o+e'er, for +ide groo'e +eld

oints or -ridg! ing across gas,a +ea'e -ead or multilestringer -eads +or)s

1 2-etter.

1 #tringer ead #tead' Mo"e-ent Along #ea

2 Wea"e ead #ide o #ideMo"eent Along #ea

Wea"e &atterns

5se wea"e $atterns to !o"er awide area in one $ass o/ teele!trode.

#-00%4-A

,*7. Poor Weld Bead #2aracteristics

1 ,arge #$atter e$osits2 Doug8 5ne"en ead

#ligt 9rater uring Welding

4 ad "erla$

% &oor &enetration

1

2 4

%

#-00%-A


18/26

1%4 %%7 &age 11


19/26

,*C. Good Weld Bead #2aracteristics

1

2 4%

1 *ine #$atter

2 5ni/or ead

Moderate 9rateruring

Welding

Weld a new bead or la'er /or ea!1


20/26

%!#T&"$ - M"+!% "F GMAW TA$%F!

$"T! $MAW transfer mode is determined -y 'aria-les such as shielding gas tye, arc'oltage, arc current, diameter of electrode and +ire feed seed.

-*1. %2ort #ircuit Transer

1 #ort 9ir!uit rans/er

#ort !ir!uit trans/er re/ers tote welding wire a!tuall' Jsort!ir!uit- ingK (tou!ing) te baseetal between :0 - 200 ties $erse!ond.

1Wit sort !ir!uit trans/er8 wire /eeds$eeds8 "oltages8 and de$ositionrates are usuall' lower tan witot- er t'$es o/ etal trans/er su!as s$ra' trans/er. is aes sort!ir- !uit trans/er "er' "ersatileallowing te welder to weld on tinor ti! etals in an' $osition.

,iitations o/ sort !ir!uit trans/erB

A relati"el' low de$osition rate

,a! o/ /usion on ti!er etals

More s$atter

o Short circuit transfer usuallyhas a crac)ling -acon frying/sound +hen a good conditione8ists.

2 #ort 9ir!uit 9'!le

A - Ele!trode is sort !ir!uited tobase etal. @o ar!8 and !urrentis /lowing troug ele!trodewire and base etal.

2 - Desistan!e in!reases in ele!-trode wire !ausing it to eat8

elt and Jne! downK.9 - Ele!trode wire se$arates /ro

weld $uddle8 !reating an ar!.#all $ortion o/ ele!trode wireis de$osited wi! /ors aweld $uddle.

- Ar! lengt and load "oltage areat aiu. 6eat o/ ar! is/lat- tening te $uddle andin!reas- ing te diaeter ti$ o/ele!- trode.

E - Wire /eed s$eed o"er!oeseat o/ ar! and wirea$$roa!es base etal again.

* - Ar! is o// and te sort!ir!uit !'!le starts again.

De/. 304 37:-A

1%4 %%7 &age 1


21/26

-*,. Glo6ular Transer

1 Globular rans/er

Globular trans/er re/ers to te stateo/ trans/er between sort-!ir!uitingand s$ra' ar! trans/er. ,argeglobs o/ wire are e$elled o// teend o/ te

1 ele!trode wire and enter teweld $uddle.

Globular trans/er !an resultwen welding $araeters su! as"oltage8 a$erage and wire /eeds$eed are soewat iger tante settings /or sort !ir!uittrans/er.

,iitations o/ globular trans/erB

&resen!e o/ s$atter

,ess desirable weld a$$earan!etan s$ra' ar! trans/er

Welding is liited to /lat$ositions and oriontall' /illetwelds

Welding is liited to etal 1


22/26

1%4 %%7 &age 14


23/26

%!#T&"$ 4 GMAW W!+&$G T"B!%""T&$G

4*1. !>cessi:e %atter

E!essi"e #$atter s!atteringo/ olten etal $arti!les tat !oolto solid /or near weld bead.

Possi6le #auses #orrecti:e Actions

Wire /eed s$eed too ig. #ele!t lower wire /eed s$eed.

Voltage too ig. #ele!t lower "oltage range.

Ele!trode etension (sti!out) too long. 5se sorter ele!trode etension (sti!out).

Wor$ie!e dirt'. Deo"e all grease8 oil8 oisture8 rust8 $aint8 under!oating8 and dirt /ro wor sur/a!e be/ore welding.

Insu//i!ient sielding gas at welding

ar!.

In!rease /low o/ sielding gas at regulator


24/26

4*-. &ncomlete Fusion

In!o$lete *usion /ailure o/weld etal to /use !o$letel' witbase etal or a $re!eeding weldbead.


Wor$ie!e dirt'. Deo"e all grease8 oil8 oisture8 rust8 $aint8 !oatings8 and dirt /ro wor sur/a!e be/ore welding.

Insu//i!ient eat in$ut. #ele!t iger "oltage range andust wire /eed s$eed.

I$ro$er welding te!ni?ue. &la!e stringer bead in $ro$er lo!ation(s) at >oint during welding.

Ad>ust wor angle or widen groo"e to a!!ess botto during welding.

Moentaril' old ar! on groo"e side walls wen using wea"ing te!ni?ue.

Fee$ ar! on leading edge o/ weld $uddle.

5se !orre!t gun angle o/ 0 to 1% degrees.

4*4. !>cessi:e Penetration

E!essi"e &enetration weldetal elting troug baseetal and anging underneatweld.


E!essi"e eat in$ut. #ele!t lower "oltage range and redu!e wire /eed s$eed.

In!rease tra"el s$eed.

4*5. ac " Penetration

,a! / &enetration sallow/usion between weld etal andbase etal.

,a! o/ &enetration Good &enetrationPossi6le #auses #orrecti:e Actions

I$ro$er >oint $re$aration. Material too ti!. oint $re$aration and design ust $ro"ide a!!ess to botto o/ groo"e wile

ain- taining $ro$er welding wire etension and ar! !ara!teristi!s.

I$ro$er weld te!ni?ue. Maintain noral gun angle o/ 0 to 1% degrees to a!ie"e aiu $enetration.

Fee$ ar! on leading edge o/ weld $uddle.

e sure welding wire etends not ore tan 1


25/26

4*@. Burn T2roug2

urn-roug weld etalelting !o$letel' troug baseetal resulting in oles were noetal re- ains.


E!essi"e eat in$ut. #ele!t lower "oltage range and redu!e wire /eed s$eed.

In!rease and


26/26

Miller !lectric Mg. #o.An Illinois ool Wors 9o$an'

1+% West #$en!er #treet

A$$leton8 WI %4:14 5#A

&nternational ead;uarters%A

5#A &oneB :20-7%-4%0% Auto-Atten

5#A 9anada *APB :20-7%-414

International *APB :20-7%-412%

!uroean ead;uarters nited

Miller Guide for Gmaw New

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