TIG Welding yog dab tsi
Tungsten inert gas (TIG) vuam, tseem hu ua roj tungsten arc vuam (GTAW), siv cov tungsten electrode uas tsis siv tau thiab cov roj inert shielding. - TIG welding tso cai rau kev sib koom ntawm cov khoom yam tsis muaj kev siv cov khoom siv muab tub lim, ua rau cov welds zoo dua thiab tsis muaj kab mob.
Nyob rau hauv TIG welding txheej txheem, lub arc yog tsim los ntawm ib tug taw tes tungsten electrode thiab workpiece nyob rau hauv ib tug inert cua ntawm argon los yog helium. Qhov me me khaus arc muab los ntawm taw tes electrode yog zoo tagnrho rau high-zoo thiab precision vuam. Vim hais tias cov electrode tsis tau noj thaum lub sij hawm vuam, TIG welder tsis tas yuav sib npaug ntawm cov cua sov tawm ntawm lub arc raws li cov hlau tso los ntawm cov electrode melting. Thaum yuav tsum tau muab tub lim hlau, nws yuav tsum tau muab sib cais rau hauv lub pas dej ua ke.
Lub zog
TIG vuam yuav tsum tau ua nrog ib tug drooping, tas li tam sim no lub hwj chim qhov chaw - DC los yog AC. Lub zog hluav taws xob tas li yog qhov tseem ceeb kom tsis txhob muaj cov khoom siv hluav taws xob ntau dhau thaum lub electrode luv luv rau ntawm qhov chaw ua haujlwm. Qhov no tuaj yeem tshwm sim yog txhob txwm tshaj tawm thaum lub sijhawm pib arc lossis inadvertently thaum vuam. Yog hais tias, raws li nyob rau hauv MIG welding, ib tug tiaj tus yam ntxwv hwj chim qhov chaw yog siv, ib qho kev sib cuag nrog lub workpiece nto yuav puas lub electrode tip los yog fuse lub electrode rau workpiece nto. Nyob rau hauv DC, vim hais tias arc cua sov faib kwv yees li ib feem peb ntawm lub cathode (tsis zoo) thiab ob feem peb ntawm lub anode (zoo), cov electrode yeej ib txwm tsis zoo polarity los tiv thaiv overheating thiab melting. Txawm li cas los xij, lwm txoj hauv kev sib txuas ntawm DC electrode zoo polarity muaj qhov zoo dua thaum lub cathode nyob rau ntawm qhov chaw ua haujlwm, qhov chaw raug ntxuav ntawm oxide paug. Vim li no, AC yog siv thaum vuam cov ntaub ntawv nrog ib tug tenacious nto oxide zaj duab xis, xws li txhuas.
Arc pib
Lub vuam arc tuaj yeem pib los ntawm khawb qhov saum npoo, ua rau luv luv. Nws tsuas yog thaum lub luv-circuit tawg uas lub ntsiab vuam tam sim no yuav ntws. Txawm li cas los xij, muaj kev pheej hmoo tias cov electrode yuav lo rau saum npoo thiab ua rau muaj tungsten suav nrog hauv cov vuam. Qhov kev pheej hmoo no tuaj yeem txo qis siv cov txheej txheem 'lift arc' qhov twg qhov luv-circuit yog tsim nyob rau theem tam sim no tsawg heev. Txoj kev zoo tshaj plaws ntawm kev pib TIG arc yog siv HF (High Frequency). HF muaj cov hluav taws xob hluav taws xob siab ntawm ntau txhiab volts uas kav ntev li ob peb microseconds. HF sparks yuav ua rau lub electrode-workpiece sib txawv los yog ionize. Thaum ib qho hluav taws xob / ion huab tau tsim, tam sim no tuaj yeem ntws los ntawm lub zog hluav taws xob.
Lus Cim: Raws li HF tsim cov khoom siv hluav taws xob tsis zoo (EM), cov vuam yuav tsum paub tias nws siv tuaj yeem cuam tshuam, tshwj xeeb tshaj yog hauv cov khoom siv hluav taws xob. Raws li EM emissions tuaj yeem tshwm sim hauv huab cua, xws li xov tooj cua tsis muaj zog, lossis xa mus rau cov hluav taws xob cables, yuav tsum tau saib xyuas kom tsis txhob cuam tshuam nrog kev tswj hwm thiab cov cuab yeej nyob ib puag ncig ntawm vuam.
HF kuj tseem ceeb hauv kev ruaj khov ntawm AC arc; Hauv AC, electrode polarity yog thim rov qab ntawm qhov zaus ntawm li 50 zaug ib ob, ua rau lub arc raug tua ntawm txhua qhov kev hloov pauv. Txhawm rau kom ntseeg tau tias lub arc yog reignited ntawm txhua qhov thim rov qab ntawm polarity, HF sparks yog tsim los ntawm cov electrode / workpiece gap rau coincide nrog pib ntawm txhua ib nrab-lub voj voog.
Cov hluav taws xob
Electrodes rau DC vuam yog ib txwm ntshiab tungsten nrog 1 mus rau 4% thoria los txhim kho arc ignition. Lwm yam additives yog lanthanum oxide thiab cerium oxide uas tau thov kom muab kev ua tau zoo tshaj (arc pib thiab qis electrode noj). Nws yog ib qho tseem ceeb los xaiv qhov tseeb electrode txoj kab uas hla thiab lub kaum sab xis rau qib ntawm vuam tam sim no. Raws li txoj cai, qhov tam sim no qis dua qhov me me ntawm electrode txoj kab uas hla thiab lub kaum sab xis. Nyob rau hauv AC vuam, raws li cov electrode yuav ua hauj lwm ntawm ib tug ntau dua kub, tungsten nrog ib tug zirconia ntxiv yog siv los txo electrode yaig. Nws yuav tsum tau muab sau tseg tias vim hais tias ntawm qhov loj ntawm cov cua kub generated ntawm lub electrode, nws yog ib qhov nyuaj rau tuav ib tug taw tes thiab qhov kawg ntawm lub electrode xav tias ib tug spherical los yog 'pob' profile.
Tiv thaiv roj
Shielding gas yog xaiv raws li cov khoom siv welded. Cov lus qhia hauv qab no yuav pab tau:
Argon + 2 mus rau 5% H2 - qhov sib ntxiv ntawm hydrogen rau argon yuav ua rau cov pa roj me ntsis, pab tsim cov khoom huv si uas tsis muaj oxidation. Raws li lub arc yog kub thiab constricted ntau, nws tso cai rau vuam ceev dua. Qhov tsis zoo muaj xws li kev pheej hmoo ntawm hydrogen cracking hauv carbon steels thiab weld hlau porosity hauv aluminium alloys.
Helium thiab helium / argon sib tov - ntxiv helium rau argon yuav nce qhov kub ntawm lub arc. Qhov no txhawb kev vuam ceev dua thiab qhov sib sib zog nqus weld nkag. Qhov tsis zoo ntawm kev siv helium lossis helium / argon sib tov yog cov nqi roj siab thiab nyuaj rau kev pib lub arc.
Daim ntawv thov
TIG vuam yog siv nyob rau hauv tag nrho cov kev lag luam sectors tab sis tshwj xeeb tshaj yog haum rau high-zoo vuam. Nyob rau hauv phau ntawv welding, qhov me me arc yog zoo tagnrho rau cov ntaub ntawv nyias los yog tswj kev nkag mus (hauv paus khiav ntawm cov yeeb nkab welds). Vim tias qhov nyiaj tso tawm tuaj yeem qis heev (siv cov pas nrig cais) MMA lossis MIG yuav zoo dua rau cov khoom tuab thiab rau cov ntawv hla hauv cov yeeb nkab tuab tuab.
TIG vuam kuj tau siv dav hauv cov tshuab tshuab xws li autogenously lossis nrog cov xaim xaim. Txawm li cas los xij, ob peb 'tawm ntawm txee' tshuab muaj rau orbital welding ntawm cov kav dej, siv hauv kev tsim cov nroj tsuag tshuaj lossis boilers. Cov txheej txheem yuav tsum tsis muaj kev txawj ntse, tab sis tus neeg teb xov tooj yuav tsum tau kawm zoo. Vim hais tias tus welder tsis muaj kev tswj hwm ntawm arc thiab weldpool tus cwj pwm, ua tib zoo saib xyuas yuav tsum tau them rau qhov kev npaj ntawm ntug (machined es tsis siv tes npaj), sib koom ua ke, thiab kev tswj ntawm vuam tsis.
