Ntxiv nrog rau cov txheej txheem txheej txheem, lwm yam txheej txheem vuam, xws li zawj qhov loj thiab qhov sib txawv, lub kaum sab xis ntawm electrode thiab workpiece, spatial txoj hauj lwm ntawm kev sib koom tes, thiab lwm yam, kuj tuaj yeem cuam tshuam rau kev tsim thiab vuam loj.
Ib. Qhov cuam tshuam ntawm welding tam sim no ntawm weld tsim
Nyob rau hauv qee yam kev mob, nrog rau qhov nce ntawm arc vuam tam sim no, qhov nkag mus tob thiab seem qhov siab ntawm qhov vuam nce, thiab qhov nkag dav dav nce me ntsis. Cov laj thawj rau qhov no yog raws li nram no:
1) Raws li lub vuam tam sim no ntawm arc vuam nce, lub arc quab yuam ua rau lub vuam nce, cov cua sov ntawm lub arc mus rau qhov vuam nce, thiab txoj hauj lwm ntawm cov cua kub txav mus, uas yog conducive rau conduction ntawm tshav kub. qhov tob ntawm lub pas dej molten thiab ua rau kom qhov tob tob tob. Qhov tob nkag mus yog kwv yees li proportional rau lub vuam tam sim no, uas yog, qhov tob tob tob H yog kwv yees li sib npaug rau Km × I. Nyob rau hauv cov mis, Km yog qhov nkag coefficient (tus naj npawb ntawm millimeters uas lub vuam tam sim no nce 100A los ua kom cov vuam nkag), uas muaj feem xyuam rau txoj kev vuam arc, txoj kab uas hla, hom tam sim no, thiab lwm yam. Saib Table {{2 }}.
Table 1-1 Kev nkag coefficient Km rau ntau yam arc vuam txoj kev thiab tsis (welding steel)
2) Lub melting ceev ntawm cov tub ntxhais los yog hlau ntawm arc vuam yog proportional rau vuam tam sim no. Raws li cov vuam tam sim no ntawm arc welding nce, lub melting ceev ntawm vuam hlau nce, thiab cov melting npaum li cas ntawm cov vuam hlau nce kwv yees li proportionally, thaum lub melting dav yog tsawg, yog li qhov vuam seam qhov siab nce.
3) Thaum lub vuam tam sim no nce, txoj kab uas hla ntawm arc kem nce, tab sis qhov tob ntawm lub arc mus rau hauv lub workpiece nce, thiab qhov txav ntawm qhov chaw arc yog txwv, yog li qhov nce ntawm qhov dav melting yog me me.
Thaum lub sij hawm gas-shielded hlau arc vuam, qhov vuam tam sim no nce thiab qhov vuam nkag tau nce. Yog tias qhov vuam tam sim no loj dhau thiab qhov ceev tam sim no siab dhau lawm, kev nkag mus rau cov ntiv tes zoo li yuav tshwm sim, tshwj xeeb tshaj yog thaum vuam aluminium.
Qhov thib ob, qhov cuam tshuam ntawm arc voltage ntawm kev tsim vuam
Nyob rau hauv tej yam kev mob, thaum lub arc voltage yog nce, lub zog arc nce raws li, thiab lub tshav kub input los ntawm weldment nce. Txawm li cas los xij, qhov nce ntawm arc voltage yog ua tiav los ntawm kev nce qhov ntev ntawm arc. Qhov nce ntawm arc ntev ua rau lub vojvoog ntawm lub arc tshav kub qhov chaw, lub tshav kub dissipation ntawm lub arc nce, thiab lub zog ceev ntawm cov input weldment txo, yog li qhov nkag mus rau qhov tob yog txo me ntsis thiab qhov tob nkag mus nce. Nyob rau tib lub sijhawm, txij li qhov vuam tam sim no tseem tsis hloov pauv, qhov melting npaum li cas ntawm cov vuam hlau yog qhov pib tsis hloov, uas txo qhov siab qhov siab.
Rau ntau yam arc vuam txoj kev, Russia thiab Nyiv yuav tsum tau tsim weld tsim, uas yog, tuav ib tug haum weld tsim coefficient φ, nce lub arc voltage kom tsim nyog thaum nce vuam tam sim no, thiab yuav tsum muaj kev sib raug zoo ntawm cov arc voltage thiab cov vuam tam sim no. . Qhov no feem ntau tshwm sim hauv molten electrode arc vuam.
Thib peb, qhov cuam tshuam ntawm vuam ceev ntawm vuam tsim
Nyob rau hauv tej yam kev mob, ua rau lub vuam ceev yuav ua rau kom txo tau cov vuam kub input, yog li txo qhov dav weld thiab nkag mus tob. Txij li thaum tus nqi ntawm cov hlau hlau deposition ntawm ib chav tsev ntev ntawm weld yog inversely proportional rau vuam ceev, nws kuj ua rau kom txo tau qhov siab weld.
Vuam ceev yog ib qho tseem ceeb Performance index los ntsuam xyuas vuam productivity. Txhawm rau txhim kho vuam tsim tau, vuam ceev yuav tsum tau nce. Txawm li cas los xij, txhawm rau kom ntseeg tau tias qhov loj me ntawm qhov xav tau los ntawm cov qauv tsim, qhov vuam tam sim no thiab arc voltage yuav tsum tau nce ntxiv thaum nce vuam ceev. Peb qhov no muaj feem cuam tshuam rau ib leeg. Nyob rau tib lub sijhawm, nws yuav tsum tau txiav txim siab tias thaum lub vuam tam sim no, arc voltage thiab vuam ceev tau nce (uas yog, lub zog vuam arc, siab vuam ceev vuam), vuam tsis zoo yuav tshwm sim hauv cov txheej txheem ntawm kev tsim cov molten. pas dej ua ke thiab thaum lub sij hawm solidification txheej txheem ntawm lub molten pas dej ua ke, xws li galling. Ntug, kab nrib pleb, thiab lwm yam, yog li muaj kev txwv kom nce qhov vuam ceev.
Plaub, qhov cuam tshuam ntawm vuam tam sim no hom thiab polarity thiab electrode loj ntawm vuam tsim
1. Hom thiab polarity ntawm vuam tam sim no
Hom vuam tam sim no muab faib ua DC thiab AC. Ntawm lawv, DC arc vuam yog muab faib ua DC tas li thiab DC pulse raws li qhov muaj lossis tsis muaj cov mem tes tam sim no; Raws li qhov polarity, nws tau muab faib ua DC qhov kev sib txuas zoo (qhov vuam yog txuas nrog qhov zoo) thiab DC thim rov qab txuas (qhov vuam yog txuas nrog qhov tsis zoo). AC arc vuam muab faib ua sine yoj AC thiab square yoj AC raws li qhov sib txawv tam sim no waveforms. Hom thiab polarity ntawm vuam tam sim no cuam tshuam cov nqi ntawm cov khoom siv hluav taws xob los ntawm cov arc rau hauv cov vuam, yog li nws tuaj yeem cuam tshuam rau kev tsim cov vuam, thiab tseem cuam tshuam rau cov txheej txheem xa dej thiab tshem tawm cov oxide zaj duab xis ntawm lub hauv paus hlau.
Thaum argon tungsten arc vuam siv los vuam hlau, titanium thiab lwm yam khoom siv hlau, qhov tob tob ntawm qhov vuam tsim thaum DC txuas yog qhov loj tshaj plaws, thiab qhov nkag mus yog qhov tsawg tshaj plaws thaum DC thim rov qab, thiab AC nyob nruab nrab ntawm ob tug. Txij li thaum qhov nkag ntawm cov vuam seam yog qhov loj tshaj plaws thaum lub sij hawm DC zoo welding, thiab tungsten electrode burning poob yog qhov tsawg tshaj plaws, DC zoo vuam yuav tsum tau siv thaum vuam hlau, titanium thiab lwm yam khoom hlau. Thaum TIG welding txais cov khoom siv DC welding, txij li cov mem tes tsis tuaj yeem hloov kho, qhov vuam seam tsim loj tuaj yeem tswj tau raws li qhov xav tau. Thaum welding aluminium, magnesium thiab lawv cov alloys los ntawm argon tungsten arc vuam, nws yog ib qho tsim nyog yuav tau siv cov cathode ntxuav cov arc los ntxuav cov oxide zaj duab xis ntawm lub hauv paus hlau. Nws yog qhov zoo dua los siv AC. Txij li cov waveform tsis ntawm square yoj AC tuaj yeem hloov kho, cov nyhuv vuam zoo dua. .
Nyob rau hauv fusion electrode arc vuam, qhov vuam qhov tob thiab qhov dav ntawm DC rov qab kev sib txuas yog ntau dua li cov kev sib txuas ntawm DC zoo, thiab qhov tob tob thiab dav ntawm AC vuam yog nyob nruab nrab ntawm ob. Yog li ntawd, nyob rau hauv submerged arc vuam, DC rov qab kev twb kev txuas yog siv kom tau ib tug loj nkag qhov tob; Thaum nyob rau hauv submerged arc surfacing vuam, DC rau pem hauv ntej kev twb kev txuas yog siv los txo qhov tob tob. Nyob rau hauv cov roj hlau arc vuam, nws yog dav siv vim hais tias DC thim rov qab kev twb kev txuas tsis tsuas yog muaj ib tug loj nkag mus rau hauv qhov tob, tab sis kuj lub vuam arc thiab droplet hloov txheej txheem yog ruaj khov dua DC zoo kev twb kev txuas thiab AC, thiab muaj ib tug cathode tu nyhuv, yog li ntawd. nws yog dav siv. Kev sib txuas lus feem ntau tsis siv.
2. Kev cuam tshuam ntawm tungsten electrode tip puab, hlau txoj kab uas hla thiab ncua ntev
Lub kaum sab xis thiab cov duab ntawm lub hauv ntej kawg ntawm lub tungsten electrode muaj kev cuam tshuam zoo rau cov concentration ntawm arc thiab arc siab, thiab yuav tsum tau xaiv raws li qhov loj ntawm vuam tam sim no thiab thickness ntawm lub vuam. Feem ntau, qhov ntau concentrated lub arc thiab ntau dua qhov arc siab, qhov ntau dua qhov tob tob thiab qhov sib thooj hauv qhov dav nkag mus.
Nyob rau hauv cov roj hlau arc vuam, thaum vuam tam sim no tas li, lub thinner vuam hlau yog, qhov ntau concentrated lub arc cua sov yog, qhov nkag mus tob zuj zus, thiab fusion dav txo. Txawm li cas los xij, thaum xaiv txoj kab uas hla ntawm lub vuam qhov project tiag tiag, qhov loj ntawm qhov tam sim no thiab cov duab ntawm lub pas dej molten yuav tsum tau txiav txim siab kom tsis txhob muaj qhov tsis zoo weld tsim.
Thaum qhov ntev ntawm cov vuam hlau ntawm MIGAW arc vuam nce, qhov kev tiv thaiv tshav kub uas tsim los ntawm cov vuam tam sim no los ntawm qhov elongated ib feem ntawm vuam hlau nce, yog li ntawd lub melting ceev ntawm vuam hlau nce, yog li qhov seem qhov siab ntawm vuam. seam nce, thaum qhov tob tob tob zuj zus. Vim yog qhov loj me me ntawm cov hlau xaim, qhov cuam tshuam ntawm cov xaim txuas ntxiv ntev ntawm kev tsim cov vuam yog pom tseeb hauv cov vuam ntawm cov hlau thiab cov hlau nyias. Lub resistivity ntawm aluminium welding hlau yog me me, thiab nws cov cawv tsis loj. Txawm hais tias qhov kev ncua ntev ntawm cov vuam hlau tuaj yeem txhim kho cov coefficient melting ntawm cov vuam hlau, muaj ntau qhov kev tso cai ntawm qhov sib txawv ntawm qhov ntev ntawm cov vuam hlau txiav txim siab qhov ruaj khov ntawm vuam hlau melting thiab vuam seam tsim.
Tsib. Kev cuam tshuam ntawm lwm yam txheej txheem ntawm vuam seam forming yam tseem ceeb
Ntxiv nrog rau cov txheej txheem saum toj no, lwm yam txheej txheem vuam, xws li zawj qhov loj thiab qhov sib txawv, lub kaum sab xis ntawm electrode thiab workpiece, thiab spatial txoj hauj lwm ntawm kev sib koom tes, kuj tuaj yeem cuam tshuam rau kev tsim thiab vuam loj.
1. Tsaus thiab qhov sib txawv
Thaum vuam pob qij txha los ntawm arc vuam, nws feem ntau txiav txim siab seb puas yuav khaws qhov sib txawv, qhov loj ntawm qhov sib txawv thiab daim ntawv ntawm qhov zawj raws li qhov tuab ntawm cov phaj welded. Nyob rau hauv qee qhov xwm txheej, qhov loj dua qhov loj ntawm qhov zawj lossis qhov sib txawv, qhov me dua qhov seem ntawm qhov siab ntawm cov welded seam, uas yog sib npaug rau qhov txo qis ntawm txoj hauj lwm ntawm vuam seam, thiab qhov sib piv ntawm qhov sib npaug yog txo rau lub sijhawm no. Yog li ntawd, qhov sib txawv los yog bevel tuaj yeem siv los tswj qhov loj ntawm lub overhang thiab kho qhov sib piv fusion. Piv nrog rau beveling nrog qhov sib txawv thiab tsis muaj qhov sib txawv, cov cua sov dissipation ntawm ob qhov sib txawv me ntsis. Feem ntau hais lus, crystallization tej yam kev mob ntawm lub bevel yog zoo dua.
2. Electrode (welding hlau) inclination
Thaum lub sij hawm arc vuam, raws li kev sib raug zoo ntawm electrode qaij kev taw qhia thiab vuam kev taw qhia, nws tuaj yeem muab faib ua ob hom: electrode pem hauv ntej qaij thiab electrode rov qab qaij. Thaum lub vuam hlau yog tilted, lub arc axis kuj tilted raws li. Thaum lub vuam hlau yog qaij rau pem hauv ntej, cov nyhuv ntawm lub zog arc ntawm qhov rov qab tawm ntawm lub pas dej molten hlau tsis muaj zog, cov kua hlau txheej hauv qab ntawm lub pas dej molten ua thicker, qhov nkag mus tob zuj zus, qhov tob ntawm lub arc. nyob rau hauv lub weldment txo, qhov txav ntawm qhov chaw arc nthuav dav, thiab qhov dav melting txo. nce, qhov seem qhov siab txo. Qhov me me ntawm lub kaum sab xis ntawm lub xaim rau pem hauv ntej inclination yog, qhov pom tseeb dua cov nyhuv yog. Thaum cov hlau tig rov qab, qhov ntxeev yog qhov tseeb. Hauv electrode arc vuam, feem ntau siv electrode rov qab qaij txoj kev, thiab lub kaum sab xis inclination zoo dua ntawm 65 degree thiab 80 degree.
3. Vuam lub kaum sab xis
Weldment inclination feem ntau ntsib hauv kev tsim khoom tiag tiag, uas tuaj yeem muab faib ua cov vuam nce toj thiab qis qis. Lub sijhawm no, lub pas dej molten hlau nyiam ntws los ntawm txoj kab nqes hauv qab qhov kev txiav txim ntawm lub ntiajteb txawj nqus. Thaum nce toj vuam, lub ntiajteb txawj nqus pab lub pas dej molten hlau tawm mus rau tus Tsov tus tw ntawm lub pas dej molten, yog li qhov nkag mus tob yog qhov loj, qhov dav melting yog nqaim, thiab qhov siab tshaj qhov loj. Thaum lub kaum sab xis saum toj yog 6 degree -12 degree, qhov siab tshaj plaws yog qhov loj heev, thiab cov undercuts yooj yim tshwm sim ntawm ob sab. Thaum lub sij hawm downhill welding, cov nyhuv no tiv thaiv lub pas dej molten hlau los ntawm kev tawm mus rau tus Tsov tus tw ntawm lub pas dej molten, thiab lub arc tsis tuaj yeem ua kom sov cov hlau nyob hauv qab ntawm lub pas dej molten. Yog hais tias lub inclination lub kaum sab xis ntawm lub weldment loj heev, nws yuav ua rau tsis txaus nkag mus thiab overflow ntawm cov kua hlau nyob rau hauv lub molten pas dej ua ke.
4. Weldment khoom thiab thickness
Lub weld nkag mus yog cuam tshuam nrog vuam tam sim no, nrog rau cov thermal conductivity thiab volumetric tshav kub muaj peev xwm ntawm cov khoom. Qhov zoo dua cov thermal conductivity ntawm cov khoom thiab qhov loj ntawm lub volumetric tshav kub muaj peev xwm, qhov ntau cua sov yuav tsum tau yaj cov hlau rau ib chav tsev ntim thiab nce tib qhov kub. Yog li ntawd, nyob rau hauv tej yam kev mob xws li welding tam sim no, qhov tob tob thiab nkag mus dav yog txo. Qhov siab dua qhov ntom ntawm cov khoom los yog cov viscosity ntawm cov kua, qhov nyuaj dua nws yog rau lub arc kom dislodge cov hlau nyob rau hauv cov kua dej molten pas dej ua ke, thiab lub qhov tob tob ntawm qhov nkag. Lub thickness ntawm lub vuam cuam tshuam rau lub tshav kub conduction nyob rau hauv lub weldment. Thaum lwm yam kev mob zoo ib yam, lub thickness ntawm lub vuam nce, lub tshav kub dissipation nce, thiab fusion dav thiab nkag mus tob.
5. Flux, electrode txheej thiab shielding roj
Qhov muaj pes tsawg leeg ntawm cov flux lossis electrode txheej yog txawv, uas ua rau sib txawv arc voltage poob thiab arc kem muaj peev xwm gradient, uas yuav inevitably cuam tshuam rau kev tsim vuam. Thaum cov flux ceev me me, qhov loj me me los yog qhov siab stacking me me, lub siab nyob ib ncig ntawm lub arc yog qis, arc kem nthuav dav, thiab qhov chaw arc txav ntau yog loj, yog li qhov tob tob yog me me, lub melting. dav yog loj, thiab residual qhov siab yog me me. Thaum lub zog siab arc vuam siv los vuam qhov tuab, kev siv cov pumice zoo li flux tuaj yeem txo qhov arc siab, txo qhov tob tob, thiab ua kom lub fusion dav. Tsis tas li ntawd, lub vuam slag yuav tsum muaj qhov tsim nyog viscosity thiab melting kub. Yog hais tias lub viscosity siab dhau lawm los yog lub melting kub siab dhau lawm, lub slag yuav tsis zoo ventilated, thiab nws yog ib qho yooj yim los tsim ntau lub siab pits rau ntawm qhov chaw ntawm weld, thiab qhov chaw ntawm weld yuav deteriorate.
Cov muaj pes tsawg leeg ntawm shielding roj (xws li Ar, Nws, N2, CO2) rau arc vuam yog txawv, thiab nws lub cev muaj zog xws li thermal conductivity yog txawv, uas ua rau lub arc ncej siab poob thiab arc kem muaj peev xwm gradient, arc kem conductive hla ntu, plasma flow force. , tshwj xeeb kub ntws faib, thiab lwm yam, uas txhua tus cuam tshuam rau kev tsim cov vuam.
Nyob rau hauv luv luv, muaj ntau yam cuam tshuam rau weld tsim. Txhawm rau kom tau txais kev tsim cov vuam zoo, nws yog qhov yuav tsum tau xaiv raws li cov khoom siv thiab cov tuab ntawm cov vuam, qhov chaw ntawm qhov vuam, daim ntawv sib koom ua ke, thiab cov kev xav tau ntawm kev ua haujlwm ntawm kev sib koom ua haujlwm thiab qhov loj me. Cov txheej txheem vuam tsim nyog thiab cov khoom siv vuam yog siv rau vuam, thiab qhov tseem ceeb tshaj plaws yog tus cwj pwm ntawm cov vuam ntawm vuam! Txwv tsis pub, kev tsim cov vuam thiab nws qhov kev ua tau zoo yuav tsis ua raws li qhov yuav tsum tau ua, thiab txawm tias muaj ntau yam vuam tsis xws luag yuav tshwm sim.
