Ntxiv rau cov yam ntxwv ntawm cov txheej txheem vuam, lwm yam yam ntxwv ntawm cov txheej txheem vuam, xws li qhov loj ntawm qhov groove thiab qhov sib txawv, lub kaum sab xis ntawm electrode thiab workpiece, thiab qhov chaw ntawm qhov sib koom ua ke, kuj tseem tuaj yeem cuam tshuam rau kev tsim weld thiab qhov loj ntawm weld.
Kev Cuam Tshuam ntawm Qhov Hluav Taws Xob Vuam rau Kev Tsim Qhov Vuam
Nyob rau hauv qee qhov xwm txheej, raws li qhov tam sim no ntawm arc vuam nce ntxiv, qhov tob nkag mus thiab kev txhawb nqa ntawm cov kab txuas ntxiv nce ntxiv, thiab qhov dav ntawm qhov txuas ntxiv nce me ntsis. Cov laj thawj yog raws li nram no:
1) Thaum lub zog vuam ntawm arc vuam nce ntxiv, lub zog arc ua rau ntawm qhov vuam nce ntxiv, qhov cua sov nkag ntawm arc mus rau qhov vuam nce ntxiv, thiab qhov chaw cua sov txav mus rau hauv qab, uas yog qhov zoo rau kev coj cua sov hauv qhov tob ntawm lub pas dej molten thiab ua rau qhov tob nkag mus. Qhov tob nkag mus yog kwv yees li sib npaug rau qhov tam sim no vuam. Qhov tob nkag mus rau hauv weld H yog kwv yees li sib npaug rau Km × I. Hauv cov mis, Km yog tus lej nkag mus (tus lej ntawm millimeters uas qhov tob nkag mus rau hauv weld nce ntxiv thaum qhov tam sim no vuam nce ntxiv los ntawm 100 A), uas yog cuam tshuam nrog txoj kev vuam arc, txoj kab uas hla hlau, hom tam sim no, thiab lwm yam raws li qhia hauv Rooj 1-1.
| cov txheej txheem vuam arc | electrode txoj kab uas hla / hli | vuam tam sim no / A | hluav taws xob/V | vuam ceev / mh-1 | coefficient nkag mus/m m-100A-1 |
| | 3.2 | 100~350 | 10~16 | 6~18 | 0.8~1.8 |
| | 1.6 lub qhov qhib ntawm lub qhov (nozzle aperture) | 50 ~ 100 | 20~26 | 10~60 | 1.2~2 |
| 3.4 lub qhov qhib ntawm lub qhov (nozzle aperture) | 220~300 | 28~36 | 18~30 | 1.5~2.4 |
| | 2 | 200~700 | 32~40 | 15~100 | 1.0~1.7 |
| 5 | 450~1200 | 34~44 | 30 ~ 60 | 0.7~1.3 |
kev sib txuas electrode argon arc vuam | 1.2~2.4 | 210~550 | 24~42 | 40 ~ 120 | 1.5~1.8 |
| CO2 vuam | 0.8~1.6 | 70 ~ 300 | 16~23 | 30 ~ 150 | 0.8~1.2 |
| 2~4 | 500~900 | 35~45 | 40 ~ 80 | |
Rooj 1-1 Melting depth coefficient Km rau ntau txoj kev vuam arc thiab cov kev ntsuas (welding steel)
2) Qhov ceev ntawm lub vuam core lossis hlau vuam hauv arc vuam yog proportional rau qhov tam sim no vuam. Txij li thaum qhov nce ntawm tam sim no vuam hauv arc vuam ua rau qhov nce ntawm qhov ceev ntawm cov hlau vuam, qhov ntau ntawm cov hlau vuam yaj nce ntxiv kwv yees li proportional, thaum qhov dav ntawm qhov vuam nce tsawg dua, yog li qhov kev txhawb nqa ntawm qhov vuam nce ntxiv.
3) Tom qab lub zog vuam nce ntxiv, txoj kab uas hla ntawm lub arc kem nce ntxiv. Txawm li cas los xij, qhov tob uas lub arc nkag mus rau hauv qhov workpiece nce ntxiv, thiab qhov txav mus los ntawm qhov chaw arc raug txwv. Yog li ntawd, qhov nce ntawm qhov dav vuam yog qhov me me.
Hauv kev vuam hlau uas muaj roj tiv thaiv (MIG), thaum lub zog vuam nce ntxiv, qhov tob ntawm qhov vuam yuav nce ntxiv. Yog tias lub zog vuam loj dhau thiab qhov ceev tam sim no siab dhau, qhov nkag mus zoo li ntiv tes yuav tshwm sim, tshwj xeeb tshaj yog thaum vuam txhuas.
Kev cuam tshuam ntawm arc voltage rau ntawm weld tsim
Nyob rau hauv qee qhov xwm txheej, thaum lub zog hluav taws xob arc nce ntxiv, lub zog arc nce ntxiv, thiab cov cua sov nkag mus rau hauv qhov vuam kuj nce ntxiv. Txawm li cas los xij, qhov nce ntawm lub zog hluav taws xob arc yog ua tiav los ntawm kev nce qhov ntev ntawm arc. Qhov nce ntawm qhov ntev ntawm arc ua rau lub vojvoog ntawm qhov chaw cua sov arc nce ntxiv thiab kev nce ntawm kev tso cua sov arc. Yog li ntawd, qhov ceev ntawm lub zog nkag mus rau hauv qhov vuam txo qis, yog li qhov tob nkag mus me ntsis txo qis thaum qhov dav ntawm lub hlaws weld nce ntxiv. Tib lub sijhawm, txij li thaum tam sim no vuam tseem tsis hloov pauv thiab qhov yaj ntawm cov hlau vuam tsis hloov pauv, qhov kev txhawb nqa ntawm lub hlaws weld txo qis.
Rau ntau txoj kev vuam arc, kom tau txais kev tsim vuam zoo, uas yog, kom tswj tau qhov coefficient tsim vuam φ kom zoo. Thaum nce qhov tam sim no vuam, qhov hluav taws xob arc yuav tsum tau nce kom zoo. Nws yog qhov yuav tsum tau ua kom qhov hluav taws xob arc thiab qhov tam sim no vuam muaj kev sib raug zoo. Qhov no feem ntau tshwm sim hauv kev vuam electrode arc.
Kev cuam tshuam ntawm qhov ceev ntawm kev vuam rau ntawm kev tsim vuam
Nyob rau hauv qee qhov xwm txheej, kev nce qhov ceev ntawm kev vuam yuav ua rau txo qis qhov kub ntawm kev vuam, yog li ntawd txo qhov dav ntawm lub hlaws vuam thiab qhov nkag mus. Txij li thaum qhov ntau ntawm cov hlau hlau uas tau tso rau hauv ib chav ntev ntawm qhov vuam yog inversely proportional rau qhov ceev ntawm kev vuam, nws kuj ua rau txo qis qhov kev txhawb nqa ntawm lub hlaws vuam.
Qhov ceev ntawm kev vuam yog ib qho cim qhia tseem ceeb rau kev ntsuam xyuas qhov ua tau zoo ntawm kev vuam. Txhawm rau txhim kho qhov ua tau zoo ntawm kev vuam, qhov ceev ntawm kev vuam yuav tsum tau nce ntxiv. Txawm li cas los xij, txhawm rau kom ntseeg tau tias qhov loj ntawm kev vuam xav tau hauv kev tsim qauv, thaum nce qhov ceev ntawm kev vuam, qhov tam sim no ntawm kev vuam thiab arc voltage yuav tsum tau nce ntxiv raws li. Peb qhov ntau no muaj feem cuam tshuam. Tib lub sijhawm, nws kuj yuav tsum xav txog tias thaum nce qhov tam sim no ntawm kev vuam, arc voltage, thiab qhov ceev ntawm kev vuam (uas yog, siv lub zog siab ntawm kev vuam arc thiab kev vuam ceev ntawm kev vuam), qhov tsis zoo ntawm kev vuam xws li kev txiav thiab tawg yuav tshwm sim thaum lub sijhawm tsim cov pas dej molten thiab cov txheej txheem khov ntawm cov pas dej molten. Yog li ntawd, qhov nce ntawm qhov ceev ntawm kev vuam yog txwv.
Kev cuam tshuam ntawm hom tam sim no vuam thiab polarity thiab electrode loj ntawm kev tsim vuam
1. Hom thiab polarities ntawm vuam tam sim no
Cov hom vuam tam sim no muab faib ua cov tam sim no ncaj qha thiab cov tam sim no hloov pauv. Ntawm lawv, cov tam sim no ncaj qha arc vuam yog muab faib ntxiv rau hauv cov tam sim no ncaj qha tas mus li thiab cov tam sim no pulsed ncaj qha raws li seb puas muaj lub pulse hauv cov tam sim no; nws yog muab faib ua qhov txuas tam sim no ncaj qha zoo (qhov vuam txuas nrog qhov zoo) thiab qhov txuas tam sim no ncaj qha rov qab (qhov vuam txuas nrog qhov tsis zoo) raws li polarity. Alternating tam sim no arc vuam yog muab faib ntxiv rau hauv sine wave alternating tam sim no thiab square wave alternating tam sim no raws li cov qauv tam sim no sib txawv. Hom thiab polarity ntawm cov tam sim no vuam tuaj yeem cuam tshuam rau qhov ntau ntawm cov cua sov nkag los ntawm arc mus rau qhov vuam, yog li nws tuaj yeem cuam tshuam rau qhov tsim ntawm vuam. Tib lub sijhawm, nws kuj tuaj yeem cuam tshuam rau cov txheej txheem hloov pauv droplet thiab tshem tawm cov zaj duab xis oxide ntawm qhov chaw ntawm cov hlau hauv paus.
Thaum siv tungsten inert gas arc vuam los vuam cov hlau xws li hlau thiab titanium, qhov nkag mus rau hauv qhov vuam yog qhov tob tshaj plaws thaum tam sim no ncaj qha txuas nrog rau hauv qhov kev taw qhia zoo, qhov nkag mus yog qhov tsawg tshaj plaws thaum tam sim no ncaj qha txuas nrog rau hauv qhov kev taw qhia rov qab, thiab alternating current yog nruab nrab ntawm ob qho. Txij li thaum qhov nkag mus rau hauv qhov vuam yog qhov tob tshaj plaws thaum tam sim no ncaj qha txuas nrog rau hauv qhov kev taw qhia zoo thiab lub tungsten electrode muaj qhov poob tsawg tshaj plaws, qhov txuas ncaj qha tam sim no zoo yuav tsum tau siv thaum siv tungsten inert gas arc vuam los vuam cov hlau xws li hlau thiab titanium. Thaum siv pulsed direct current vuam hauv tungsten inert gas arc vuam, txij li cov kev teeb tsa pulse tuaj yeem hloov kho, qhov loj me ntawm qhov vuam tuaj yeem tswj tau raws li qhov xav tau. Thaum siv tungsten inert gas arc vuam los vuam txhuas, magnesium, thiab lawv cov alloys, nws yog qhov tsim nyog siv cov nyhuv ntxuav cathode ntawm arc los ntxuav cov zaj duab xis oxide ntawm qhov chaw ntawm cov hlau puag. Alternating current zoo dua. Txij li thaum cov kev teeb tsa waveform ntawm square wave alternating current tuaj yeem hloov kho, qhov cuam tshuam vuam zoo dua.
Hauv kev vuam hlau roj arc, thaum qhov hluav taws xob ncaj qha txuas nrog rov qab, qhov nkag mus ntawm qhov vuam thiab qhov dav ntawm qhov vuam yog ob qho tib si loj dua li cov uas muaj kev sib txuas zoo ntawm qhov hluav taws xob ncaj qha. Qhov nkag mus thiab dav ntawm kev vuam tam sim no hloov pauv yog nyob nruab nrab ntawm ob qho tib si. Yog li ntawd, hauv kev vuam arc hauv qab dej, kev sib txuas rov qab ncaj qha feem ntau yog siv los ua kom nkag mus ntau dua; thaum nyob rau hauv kev vuam arc hauv qab dej, kev sib txuas zoo ntawm qhov hluav taws xob ncaj qha yog siv los txo qhov nkag mus. Hauv kev vuam hlau roj arc nrog cov roj tiv thaiv, txij li kev sib txuas tam sim no ncaj qha rov qab tsis yog tsuas yog muaj qhov tob tob xwb, tab sis kuj tseem muaj kev vuam arc thiab cov txheej txheem hloov pauv dej khov ruaj khov dua li cov uas muaj kev sib txuas zoo ntawm qhov hluav taws xob ncaj qha thiab kev hloov pauv tam sim no, thiab nws muaj cov nyhuv ntxuav cathode, nws yog siv dav. Kev sib txuas zoo ntawm qhov hluav taws xob ncaj qha thiab kev hloov pauv tam sim no feem ntau tsis siv.
2. Kev cuam tshuam ntawm cov duab ntawm lub taub hau tungsten electrode, txoj kab uas hla ntawm cov hlau vuam & qhov ntev ntawm qhov txuas ntxiv
Lub kaum sab xis thiab cov duab ntawm qhov kawg ntawm lub tun, gsten electrode muaj feem cuam tshuam ntau dua rau qhov concentration ntawm arc thiab arc siab. Lawv yuav tsum tau xaiv raws li qhov tam sim no vuam thiab qhov tuab ntawm cov khoom ua haujlwm. Feem ntau, qhov ntau concentration ntawm arc thiab qhov ntau dua ntawm arc siab, qhov ntau dua qhov nkag mus tob, thaum qhov dav ntawm weld txo qis.
Hauv kev siv roj hlau arc vuam, thaum lub zog vuam tam sim no tas li, cov hlau vuam nyias dua, qhov kub arc ntau dua, qhov tob nkag mus ntxiv, thiab qhov dav ntawm qhov vuam txo qis. Txawm li cas los xij, thaum xaiv txoj kab uas hla ntawm cov hlau vuam hauv cov haujlwm vuam tiag tiag, qhov loj tam sim no thiab cov qauv ntawm cov pas dej vuam yuav tsum tau xav txog kom tsis txhob muaj kev tsim cov vuam tsis zoo.
Thaum qhov ntev ntawm cov hlau txuas ntxiv hauv cov roj hlau arc vuam nce ntxiv, qhov kub tiv taus uas tsim los ntawm cov hluav taws xob vuam hla dhau qhov ntev ntawm cov hlau nce ntxiv, uas ua rau cov hlau yaj ceev nce ntxiv. Yog li ntawd, qhov kev txhawb nqa vuam nce ntxiv, thaum qhov tob nkag mus txo qis me ntsis. Vim yog qhov resistivity loj ntawm cov hlau vuam hlau, qhov cuam tshuam ntawm qhov ntev ntawm cov hlau txuas ntxiv rau kev tsim vuam yog qhov pom tseeb hauv kev vuam nrog cov hlau thiab cov hlau zoo. Qhov resistivity ntawm cov hlau vuam txhuas yog qhov me me, yog li nws qhov cuam tshuam tsis tseem ceeb. Txawm hais tias kev nce qhov ntev ntawm cov hlau txuas ntxiv tuaj yeem txhim kho cov coefficient ntawm cov hlau yaj, xav txog cov yam ntxwv ntawm kev ruaj khov ntawm cov hlau yaj thiab kev tsim vuam, muaj qhov sib txawv ntawm qhov ntev ntawm cov hlau txuas ntxiv.
Kev cuam tshuam ntawm lwm yam txheej txheem ntawm cov yam ntxwv ntawm kev tsim weld
Ntxiv rau cov yam ntxwv saum toj no, lwm yam yam ntxwv ntawm cov txheej txheem vuam, xws li qhov loj ntawm qhov groove thiab qhov sib txawv, lub kaum sab xis ntawm electrode thiab workpiece, thiab qhov chaw ntawm qhov sib koom ua ke, kuj tseem tuaj yeem cuam tshuam rau kev tsim weld thiab qhov loj ntawm weld.
1. Groove thiab qhov sib txawv
Thaum vuam cov pob qij txha los ntawm kev siv hluav taws xob arc vuam, feem ntau txiav txim siab seb puas yuav tsum tseg qhov sib txawv, qhov loj ntawm qhov sib txawv thiab cov duab ntawm qhov qhib raws li qhov tuab ntawm lub phaj vuam. Hauv qee qhov xwm txheej, qhov loj ntawm qhov sib txawv lossis qhov sib txawv loj dua, qhov kev txhawb nqa ntawm qhov vuam sib txawv me dua, uas sib npaug rau qhov chaw vuam poob qis. Lub sijhawm no, qhov sib piv sib xyaw ua ke txo qis. Yog li ntawd, tawm hauv qhov sib txawv lossis qhib qhov sib txawv tuaj yeem siv los tswj qhov loj ntawm qhov txhawb nqa thiab kho qhov sib piv sib xyaw. Piv nrog tawm hauv qhov sib txawv thiab tsis tawm hauv qhov sib txawv thiab qhib qhov sib txawv, cov xwm txheej cua sov ntawm ob qho sib txawv me ntsis. Feem ntau hais lus, cov xwm txheej crystallization ntawm kev qhib qhov sib txawv zoo dua.
2. Electrode (hlau vuam) inclination
Thaum lub sijhawm vuam arc, raws li kev sib raug zoo ntawm qhov kev taw qhia ntawm electrode thiab qhov kev taw qhia ntawm vuam, nws muab faib ua ob hom: electrode forward inclination thiab electrode backward inclination. Thaum cov hlau vuam raug inclined, lub arc axis kuj raug inclined raws li. Thaum cov hlau vuam raug inclined mus rau pem hauv ntej, qhov cuam tshuam ntawm lub zog arc ntawm kev tso tawm cov hlau molten rov qab yog qaug zog. Cov txheej hlau kua ntawm qab ntawm lub pas dej molten ua tuab dua, qhov tob nkag mus txo qis, qhov tob uas arc nkag mus rau hauv qhov vuam raug txo qis, qhov txav mus los ntawm qhov chaw arc raug nthuav dav, qhov dav ntawm qhov vuam raug nce ntxiv, thiab qhov kev txhawb nqa raug txo qis. Lub kaum sab xis α ntawm cov hlau vuam me dua, qhov cuam tshuam no pom tseeb dua. Thaum cov hlau vuam raug inclined rov qab, qhov xwm txheej yog qhov sib txawv. Hauv kev vuam hlau shielded arc, txoj kev electrode backward inclination feem ntau yog siv, thiab lub kaum sab xis α ntawm 65 ° thiab 80 ° yog qhov tsim nyog.
3. Kev vuam daim inclination
Feem ntau qhov kev sib txuas ntawm cov hlau sib txuas (weld inclination) feem ntau ntsib thaum tsim khoom tiag tiag thiab muab faib ua kev sib txuas ntawm cov hlau nce toj thiab kev sib txuas ntawm cov hlau nqes hav. Lub sijhawm no, nyob rau hauv qhov kev ua ntawm lub ntiajteb txawj nqus, cov hlau pas dej uas yaj yuav ntws mus rau hauv qab ntawm lub roob. Hauv kev sib txuas ntawm cov hlau nce toj, lub ntiajteb txawj nqus pab tso cov hlau pas dej uas yaj mus rau sab nraub qaum ntawm lub pas dej uas yaj, yog li qhov nkag mus tob, qhov dav ntawm qhov vuam nqaim, thiab qhov txhawb nqa siab. Thaum lub kaum sab xis nce toj α yog 6 ° txog 12 °, qhov txhawb nqa loj dhau, thiab qhov tsis sib xws yooj yim tsim rau ob sab. Hauv kev sib txuas ntawm cov hlau pas dej uas yaj, qhov cuam tshuam no tiv thaiv cov hlau pas dej uas yaj kom tsis txhob raug tso tawm mus rau sab nraub qaum ntawm lub pas dej uas yaj. Lub arc tsis tuaj yeem ua kom cov hlau kub tob hauv qab ntawm lub pas dej uas yaj, qhov nkag mus raug txo qis, qhov txav mus los ntawm qhov chaw arc raug nthuav dav, qhov dav ntawm qhov vuam nce ntxiv, thiab qhov txhawb nqa raug txo qis. Yog tias lub kaum sab xis ntawm qhov txuas loj dhau, nws yuav ua rau tsis txaus nkag mus thiab cov hlau dej pas dej uas yaj ntau dhau.
4. Cov khoom siv vuam thiab tuab
Kev nkag mus rau hauv qhov vuam yog cuam tshuam nrog qhov tam sim no vuam thiab kuj rau qhov thermal conductivity thiab volumetric cua sov muaj peev xwm ntawm cov khoom siv. Qhov zoo dua qhov thermal conductivity ntawm cov khoom siv thiab qhov ntau dua qhov volumetric cua sov muaj peev xwm, qhov ntau dua cua sov yog xav tau los yaj ib chav ntim ntawm cov hlau thiab nce qhov kub los ntawm tib tus nqi. Yog li ntawd, nyob rau hauv qee qhov xwm txheej xws li vuam tam sim no, qhov tob nkag mus thiab qhov dav vuam yuav txo qis. Qhov ntau dua qhov ceev lossis kua viscosity ntawm cov khoom siv, nws nyuaj dua rau lub arc los hloov cov kua dej molten pas dej hlau, thiab qhov tob nkag mus rau hauv qhov vuam. Qhov tuab ntawm qhov vuam cuam tshuam rau qhov cua sov conduction hauv qhov vuam. Thaum lwm yam xwm txheej zoo ib yam, raws li qhov tuab ntawm qhov vuam nce ntxiv, qhov cua sov dissipation nce ntxiv, thiab ob qho tib si qhov dav vuam thiab qhov tob nkag mus txo qis.
5. Flux, electrode txheej thiab shielding roj
Cov khoom sib txawv ntawm cov fluxes lossis electrode coatings ua rau muaj qhov sib txawv voltage poob ntawm thaj tsam electrode ntawm lub arc thiab sib txawv qhov sib txawv ntawm cov gradients ntawm lub arc kem, uas yuav cuam tshuam rau qhov tsim weld. Thaum lub flux muaj qhov ceev tsawg, qhov loj ntawm cov khoom me me, lossis qhov siab me me, qhov siab nyob ib puag ncig lub arc qis, lub arc kem nthuav dav, thiab qhov chaw arc muaj ntau qhov kev txav mus los. Yog li ntawd, qhov nkag mus me me, qhov dav ntawm weld loj, thiab qhov kev txhawb nqa me me. Thaum lub zog siab arc vuam siv los vuam cov khoom ua haujlwm tuab, kev siv pumice-zoo li flux tuaj yeem txo qhov siab arc, txo qhov nkag mus, thiab nce qhov dav ntawm weld. Tsis tas li ntawd, lub welding slag yuav tsum muaj viscosity thiab melting kub. Yog tias viscosity siab dhau lossis qhov kub melting siab heev, lub slag yuav muaj qhov cua tsis zoo, thiab nws yooj yim los tsim ntau qhov kev nyuaj siab ntawm qhov chaw weld, ua rau qhov tsim ntawm qhov chaw weld tsis zoo.
Cov khoom sib xyaw ua ke ntawm cov pa roj tiv thaiv rau arc vuam (xws li Ar, He, N2, CO2) yog txawv, thiab lawv cov khoom siv lub cev xws li thermal conductivity kuj txawv. Qhov no ua rau qhov voltage poob ntawm thaj tsam polar ntawm arc thiab qhov gradient ntawm arc kem, qhov conductive cross-section ntawm arc kem, lub zog ntws plasma, thiab kev faib tawm ntawm cov cua sov tshwj xeeb txawv. Tag nrho cov yam no cuam tshuam rau kev tsim cov weld seams.
Hauv ntej, muaj ntau yam uas cuam tshuam rau kev tsim cov vuam. Yuav kom tau txais kev tsim cov vuam zoo, nws yog ib qho tsim nyog los xaiv cov txheej txheem vuam thiab cov xwm txheej vuam tsim nyog rau kev vuam raws li cov khoom siv thiab tuab ntawm qhov vuam, qhov chaw ntawm qhov vuam, daim ntawv sib koom ua ke, cov xwm txheej ua haujlwm, cov kev cai rau kev ua haujlwm sib koom ua ke thiab qhov loj ntawm vuam. Tib lub sijhawm, qhov tseem ceeb tshaj plaws yog tus neeg vuam txoj kev xav txog kev vuam! Txwv tsis pub, qhov tsim cov vuam thiab nws cov kev ua tau zoo yuav tsis ua tau raws li qhov yuav tsum tau ua, thiab txawm tias ntau yam kev puas tsuaj vuam yuav tshwm sim.
