Dab tsi ua rau vuam tsis xws luag thiab yuav ua li cas nrog lawv

 

 

Raws li qhov tseem ceeb ntawm kev tsim khoom niaj hnub, qhov zoo ntawm vuam ncaj qha cuam tshuam rau tag nrho cov kev ua tau zoo thiab kev nyab xeeb ntawm cov khoom. Txawm li cas los xij, vim muaj ntau yam hauv cov txheej txheem vuam, ntau yam vuam tsis xws luag feem ntau tshwm sim. Cov kev tsis zoo no tsis yog tsuas yog txo lub zog, ua haujlwm ntev, thiab pom ntawm cov pob qij txha, tab sis kuj tseem tuaj yeem ua rau muaj kev nyab xeeb loj. Yog li ntawd, kev nkag siab txog qhov ua rau vuam tsis xws luag thiab lawv cov kev kho mob yog qhov tseem ceeb rau kev txhim kho vuam zoo thiab ua kom cov khoom ua tau zoo.

 

▲ Welding Defects

 

 

I Classification of Welding Defects

 

Welding defects tuaj yeem faib ua ob hom raws li lawv txoj haujlwm hauv cov vuam: sab nraud thiab sab hauv tsis xws luag. Sab nraud tsis xws luag, tseem hu ua cov tsos mob tsis xws luag, yog nyob rau ntawm qhov chaw ntawm lub weld thiab tuaj yeem pom nrog lub qhov muag liab qab lossis qis qis, xws li undercutting, weld spatter, concavities, vuam deformations, nto porosity, thiab nto tawg. Internal defects muaj nyob rau hauv lub weld thiab tsuas tuaj yeem kuaj tau los ntawm kev kuaj kev puas tsuaj lossis kev kuaj tshwj xeeb uas tsis muaj kev puas tsuaj, xws li tsis muaj fusion, tsis tiav kev nkag mus, sab hauv porosity, slag inclusions, thiab tawg.

 

 

II Ua rau Vuam Tsis Zoo

 

1. Sab nrauv tsis zoo

 

(1) Kev txiav txim siab

Undercutting yog hais txog kev nyuaj siab los yog grooves sab laug ntawm cov npoo ntawm lub vuam tom qab lub hauv paus hlau yog melted los ntawm arc los yog nplaim taws thiab tsis sau los ntawm weld hlau. Cov laj thawj tseem ceeb muaj xws li cov vuam tam sim no ntau dhau, qhov ntev ntev ntawm arc, qhov tsis zoo electrode (welding wire) lub kaum sab xis lossis txav, thiab qhov vuam ceev tsis raug.

 

▲ Kev txiav txim siab

 

(2) Weld Spatter

Weld spatter yog hais txog cov hlau molten weld uas ntws mus rau hauv lub hauv paus hlau los yog cov hauv paus hniav ntawm cov vuam tsis txaus thaum lub sij hawm vuam txheej txheem thiab cov ntaub ntawv lumps ntawm hlau uas tsis fuse nrog lub hauv paus khoom tom qab txias. Qhov ua rau muaj xws li electrode tsis zoo, vuam tam sim no ntau dhau, ntev arc, qeeb vuam ceev, thiab lub kaum sab xis electrode tsis zoo thiab txav.

 

▲ Weld Spatter

 

(3) Concavities thiab Vuam Deformations

Concavities feem ntau yog tshwm sim los ntawm qhov tsis ua hauj lwm los tuav lub electrode (vuam hlau) rau lub sij hawm luv luv thaum txiav cov arc, ua rau arc craters. Vuam deformations tej zaum yuav tshwm sim los ntawm kev npaj tsis txaus, cov khoom siv tsis zoo, lossis kev ua haujlwm tsis txaus.

 

▲ Concavities thiab Vuam Deformations

 

(4) Nto Porosity

Deg porosity tshwm sim thaum cov roj tsis tuaj yeem khiav tawm ntawm lub pas dej ua ke thaum vuam, tsim qhov rau ntawm qhov chaw ntawm cov hlau vuam. Cov laj thawj tseem ceeb muaj xws li kev tsis ua raws li cov khoom siv vuam thiab cov khoom ua haujlwm nrog cov txheej txheem, tsis tshua muaj vuam tam sim no, vuam ceev heev, ntev ntev arc, thiab kev tiv thaiv tsis txaus ntawm qhov chaw vuam.

 

2. Sab hauv tsis zoo

 

(1) Tsis muaj fusion thiab tsis tiav kev nkag

Tsis muaj fusion yog hais txog qhov chaw uas cov hlau tsis sib txuas nrog lub hauv paus hlau lossis nruab nrab ntawm cov khaubncaws sab nraud povtseg. Incomplete penetration yog hais txog qhov tsis ua tiav ntawm kev sib koom ua ke hauv paus thaum vuam. Cov kev tsis zoo no yog tshwm sim los ntawm qhov tsis txaus vuam tam sim no, vuam ceev heev, tsim tsis zoo groove, lub kaum sab xis electrode tsis raug, thiab cov txheej txheem vuam tsis zoo.

 

▲ Tsis muaj fusion thiab tsis tiav kev nkag mus

 

(2) Slag suav nrog

Slag inclusions hais txog cov seem slag sab laug hauv qhov vuam tom qab vuam. Qhov ua rau muaj xws li vuam tsis tshua muaj tam sim no, vuam ceev heev, qhov chaw ua haujlwm tsis huv, tshem tawm slag tsis tiav hauv ntau txheej vuam, thiab tsis zoo electrode.

 

▲ Slag suav nrog

 

(3) Kev tawg

Cov kab nrib pleb yog ib qho kev puas tsuaj loj tshaj plaws hauv cov pob qij txha, thiab qhov ua rau yog qhov nyuaj thiab ntau yam. Lawv suav nrog cov txheej txheem vuam tsis zoo, cov khoom siv vuam tsis raug, kev ntxhov siab sab hauv hauv vuam, siab tawg rhiab heev ntawm cov khoom, thiab tsis zoo ntawm cov khoom muab tub lim. Tsis tas li ntawd, qhov sib txawv ntawm cov kab nrib pleb, xws li kub tawg, tawg tawg, thiab rov ua kom tawg, yog tshwm sim los ntawm ntau yam.

 

▲ Kev tawg

 

 

III Cov Kev Kho rau Vuam Tsis Zoo

 

1. Kev kho mob sab nraud

 

(1) Kev txiav txim siab

Me me thiab ntiav undercutting yuav smoothed mechanically los tsim ib tug du kev hloov. Kev hnyav thiab tob tob yuav tsum tau kho los ntawm vuam. Kev tiv thaiv muaj xws li xaiv cov txheej txheem vuam tsim nyog, tswj qhov ntev arc, thiab paub txog cov txheej txheem tsim nyog electrode txav.

 

(2) Weld Spatter

Weld spatter tuaj yeem raug tshem tawm los ntawm kev sib tsoo tshuab, thiab cov vuam yuav tsum tau rov ua dua kom rov zoo dua. Kev tiv thaiv muaj xws li xaiv qhov tsim nyog vuam tam sim no thiab lub kaum sab xis ntawm lub electrode thiab tswj xyuas qhov sib xws ntawm vuam ceev.

 

(3) Concavities thiab Vuam Deformations

Concavities thiab vuam deformations tuaj yeem raug kho los ntawm kev sib tsoo, kho tshuab ncaj, lossis kev kho cua sov. Kev tiv thaiv muaj xws li kev npaj kom zoo ua ntej vuam, siv cov khoom tsim nyog, thiab ua cov kauj ruam los tshem tawm cov seem deformations.

 

(4) Nto Porosity

Deg porosity tuaj yeem raug tshem tawm los ntawm kev sib tsoo thiab rov vuam kom sau cov voids. Kev tiv thaiv kev tiv thaiv muaj xws li ntxuav cov khoom siv vuam thiab cov khoom ua haujlwm, xaiv qhov tsim nyog vuam tam sim no thiab ceev, thiab txhim kho kev tiv thaiv ntawm qhov chaw vuam.

 

 

2. Kev kho mob sab hauv

 

(1) Tsis muaj fusion thiab tsis tiav kev nkag

Tsis muaj fusion thiab tsis tiav kev nkag mus rau qhov tsis xws luag feem ntau yuav tsum tau kho vuam los yog gouging thiab rov vuam. Rau cov qauv qhib, kev kho ncaj nraim tuaj yeem ua tiav ntawm qhov chaw nkag tsis tiav. Rau qhov tseem ceeb weldments qhov kev kho ncaj qha tsis ua tau, cov hlau vuam hauv qhov chaw puas yuav tsum raug tshem tawm tag nrho ua ntej rov vuam.

 

(2) Slag suav nrog

Slag inclusions yuav tsum tau muab tshem tawm los ntawm khawb tawm qhov chaw puas ua ntej rov vuam. Kev tiv thaiv muaj xws li kev txhim kho qhov chaw tu, xaiv qhov tsim nyog vuam tam sim no thiab ceev, thiab xyuas kom meej slag tshem tawm ntawm cov txheej weld.

 

(3) Kev tawg

Kev kho qhov tawg yog qhov nyuaj dua thiab xav tau kev ntsuas tshwj xeeb raws li hom thiab qhov chaw ntawm qhov tawg. Rau qhov kub thiab rov ua kom tawg, qhov chaw puas yuav tsum tau muab tshem tawm, thiab qhov vuam rov ua tiav, nrog kev tswj xyuas qhov kub thiab txias thiab ntsuas kev ntxhov siab thaum vuam. Cov kab nrib pleb txias yuav xav tau cua sov, kho qhov siab, lossis lwm txoj hauv kev kho thiab tiv thaiv.

 

 

IV Case Studies of Specific Welding Defects

 

1. Kev ua tsis raws cai

• Phenomenon:Kev nyuaj siab los yog grooves uas tshwm sim raws li cov ntiv taw vuam los yog hauv paus thaum lub sij hawm vuam, qis dua cov khoom siv hauv paus.
• Ua rau:Tshaj vuam tam sim no, ntev ntev arc, tsis zoo electrode (vuam hlau) lub kaum ntse ntse, vuam ceev heev, thiab lwm yam.
• Kev cuam tshuam:Weakens weld ob leeg lub zog, tsim kev ntxhov siab concentration, thiab txo lub neej qaug zog.

 

2. Weld Spatter Defects

• Phenomenon:Cov hlau lumps tsim los ntawm cov hlau molten ntws tawm sab nraud ntawm qhov vuam mus rau cov khoom siv hauv paus tsis siv.
• Ua rau:Tshaj vuam tam sim no, vuam qeeb heev, tsis zoo electrode (vuam hlau) lub kaum ntse ntse, thiab lwm yam.
• Kev cuam tshuam:Muaj feem cuam tshuam rau qhov pom, tsim cov ntsiab lus kev ntxhov siab, thiab cuam tshuam qhov nruab nrab ntws hauv cov kav dej.

 

3. Porosity Defects

• Phenomenon:Gas hnab tshos tsim nyob rau hauv los yog nyob rau saum npoo ntawm weld hlau thaum roj tsis khiav thaum vuam.
• Ua rau:Cov dej noo hauv cov khoom siv vuam, cov roj tsis huv, cov khoom siv vuam ceev heev, ntev ntev arc, thiab lwm yam.
• Kev cuam tshuam:Txo cov weld compactness, txo qhov kev ua haujlwm zoo ntawm qhov sib tsoo ntawm qhov vuam, thiab cuam tshuam rau qhov vuam cov khoom siv tshuab.

 

4. Slag Inclusion Defects

• Phenomenon:Non-metallic inclusions nyob rau hauv weld hlau.
• Ua rau:Tsawg vuam tam sim no, vuam ceev heev, qhov tsis huv, tshem tawm slag tsis tiav ntawm cov txheej hauv ntau txheej vuam, thiab lwm yam.
• Kev cuam tshuam:Muaj feem xyuam rau weld mechanical zog thiab compactness, uas ua rau weld cracking.

 

5. Tsis muaj kev sib xyaw ua ke thiab tsis tiav kev nkag mus tsis zoo

• Phenomenon:Tsis muaj fusion yog hais txog qhov tsis tiav fusion ntawm cov hlau weld thiab cov khoom siv hauv paus lossis nruab nrab ntawm cov khaubncaws sab nraud povtseg. Incomplete penetration yog hais txog qhov tsis tiav fusion ntawm cov hauv paus hniav sib koom ua ke thaum vuam.
• Ua rau:Tsis tshua muaj vuam tam sim no, vuam ceev heev, tsis zoo groove tsim, tsis zoo electrode (welding hlau) lub kaum sab xis, thiab lwm yam.
• Kev cuam tshuam: Significantly txo cov neeg kho tshuab cov khoom ntawm vuam, ua rau nws yog ib qho ntawm feem txaus ntshai tsis xws luag nyob rau hauv vuam.

 

6. Kev ua txhaum cai

• Phenomenon:Tshiab interfaces tsim los ntawm kev puas tsuaj ntawm atomic bonding rog nyob rau hauv ib cheeb tsam ntawm lub weld sib koom tes.
• Ua rau:Kev ntxhov siab seem ntawm vuam, cov khoom siv tsis zoo ntawm cov khoom siv hauv paus lossis cov khoom siv muab tub lim, xaiv cov txheej txheem vuam tsis raug, thiab lwm yam.
• Kev cuam tshuam:Cov lus qhia ntse tawg ua rau muaj kev ntxhov siab loj heev, cuam tshuam rau cov qauv kev hloov pauv thiab cuam tshuam rau kev thauj khoom, tejzaum nws ua rau kev ua haujlwm tsis zoo.

 

 

V Xaus

 

Qhov ua rau vuam tsis xws luag yog ntau haiv neeg, thiab cov kev kho yuav tsum tau ua kom haum rau cov xwm txheej tshwj xeeb. Thaum cov txheej txheem vuam tiag tiag, kev ua raws li cov txheej txheem vuam tshwj xeeb, txhim kho kev tswj xyuas kom zoo, thiab tshawb xyuas lub sijhawm thiab kho qhov tsis xws ntawm vuam yog qhov tseem ceeb rau kev ua kom cov vuam sib txuas zoo thiab tag nrho cov khoom ua tau zoo. Tsis tas li ntawd, nrog rau kev txhim kho txuas ntxiv thiab kev nce qib ntawm vuam tshuab, cov txheej txheem vuam tshiab thiab cov ntaub ntawv tau tshwm sim, muab kev txhawb zog ntxiv rau kev txhim kho vuam zoo thiab ua haujlwm zoo.