Ntau tus welders uas tshiab rau kev lag luam txhuas tsis paub yuav ua li cas vuam ntshiab txhuas daim hlau. Kab lus no yuav qhia koj txog txoj kev vuam thiab cov txheej txheem ntawm txhuas phaj rau koj siv:
1. Kev npaj cov khoom siv tswv yim: Thaum vuam aluminium, tus welder yuav tsum ua tib zoo ntxuav cov khoom siv hauv paus thiab siv cov roj los yog cov kuab tshuaj kom tshem tawm cov oxides thiab hydrocarbons ntawm cov khoom txhuas. Cov oxide nyob rau saum npoo ntawm aluminium melts ntawm 3700 degrees Fahrenheit, thaum lub hauv paus aluminium-raws li cov hlau melts ntawm 1200 degrees Fahrenheit, yog li cov residual oxide nyob rau saum npoo ntawm aluminium-raws li hlau yuav txwv kev nkag mus ntawm cov hlau muab tub lim rau hauv workpiece. .
2. Yuav kom tshem tawm cov oxides ntawm lub txhuas nto, koj tuaj yeem siv cov hlau tsis muaj hlau txhuam los yog hnyav corrosion. Thaum siv cov txhuam hniav stainless hlau, koj tuaj yeem txhuam tsuas yog nyob rau hauv qhov chaw ruaj khov. Ceev faj tsis txhob siv lub zog ntau dhau thiab roughness, txwv tsis pub cov oxides yuav raug muab tso rau hauv cov hlau uas muaj txhuas.
3. Tshuaj ntxuav
Kev ntxuav tshuaj muaj kev ua haujlwm siab thiab ruaj khov zoo. Nws yog qhov tsim nyog rau kev ntxuav cov hlau uas tsim los ntawm cov hlau thiab cov khoom me me. Ob txoj kev tuaj yeem siv tau: soaking thiab txhuam. Petroleum tuaj yeem raug tshem tawm ntawm qhov chaw ntawm cov kuab tshuaj organic xws li acetone, roj av thiab roj av. Siv 5% - Alkaline ntxuav nrog 10% NaOH tov ntawm 40 ~ 70 degree rau 3 ~ 7 feeb (ntshiab txhuas siv sij hawm ntev me ntsis, tab sis tsis ntau tshaj 20 feeb), yaug nrog dej ntws, thiab tom qab ntawd pickle nrog 30% HNO3 tov ntawm chav tsev kub rau 30 vib nas this ntawm 60 degree% HNO3 li ntawm 2 feeb, yaug nrog dej ntws, qhuav los ntawm infrared rays los yog qhuav ntawm qhov kub thiab txias.
4. Tom qab lub workpiece thiab vuam hlau tau raug ntxuav thiab ntxuav, oxide zaj duab xis yuav rov tsim dua thaum lub sij hawm cia. Tshwj xeeb tshaj yog nyob rau hauv ib puag ncig humid, thiab nyob rau hauv ib puag ncig uas kis los ntawm vapors xws li acids thiab alkalis, oxide zaj duab xis yuav loj hlob sai. Yog li ntawd, lub sij hawm cia tom qab ntxuav thiab ntxuav ntawm lub workpiece thiab vuam hlau ua ntej vuam yuav tsum tau luv luv kom ntau li ntau tau. Hauv cov huab cua ntub, vuam feem ntau yuav tsum tau ua hauv 4 teev tom qab ntxuav. Yog tias lub sijhawm khaws cia tom qab tu ntev dhau lawm (xws li ntau dua 24 teev) yuav tsum rov ua dua.
5. Preheating: Preheating ntshiab txhuas daim hlau yuav pab tau kom tsis txhob vuam tawg. Qhov kub preheating yuav tsum tsis pub tshaj 230 degrees Fahrenheit. Siv lub ntsuas kub ntsuas kub los ntsuas qhov ntsuas kub kom tsis txhob kub dhau. Tsis tas li ntawd, muab cov welding sib quas ntus thaum pib thiab xaus ntawm qhov chaw vuam tuaj yeem pab ua kom cov cua sov ua kom zoo dua. Thaum welding nyias cov ntaub ntawv, welders yuav tsum tau preheat tuab aluminium ntawv.
6. Kev ua haujlwm ceev: Cov txheej txheem txhuas vuam yuav tsum tau ua "siab kub thiab kub ceev" ua. Tsis zoo li cov hlau, lub siab thermal conductivity ntawm txhuas yuav tsum muaj zog dua tam sim no thiab qhov hluav taws xob los teeb tsa ntawm qhov kub thiab txias thiab vuam ceev. Yog tias qhov vuam ceev qeeb dhau, qhov vuam yaj yuav Qhov tob yuav loj dhau, tshwj xeeb tshaj yog thaum vuam cov ntaub ntawv nyias.
7. Shielding gas: Vim nws zoo heev tu kev ua tau zoo, argon yog siv raws li ib tug nquag siv shielding gas rau txhuas welding. Thaum welding 5XXX-series ntshiab aluminium alloys, cov roj siv tiv thaiv yog sib xyaw ntawm argon thiab helium. Ib qho helium piv ntawm 75% tuaj yeem ua tiav qhov zoo tshaj plaws ntawm kev txo qis ntawm magnesium oxide.
8. Ntxuav tom qab vuam
Cov flux thiab slag tshuav nyob rau hauv thiab sab nraum lub vuam tom qab vuam yuav rhuav tshem cov zaj duab xis passivation ntawm aluminium nto thiab qee zaum corrode aluminium qhov chaw. Lawv yuav tsum tau ntxuav. Cov duab yooj yim thiab cov khoom siv dav dav tuaj yeem raug ntxuav nrog txoj hauv kev yooj yim, xws li dej kub yaug lossis Chav purging: Rau cov ntawv txhuas ntshiab uas muaj cov kev xav tau siab thiab cov duab nyuaj, siv cov txhuam tawv tawv los ntxuav lawv hauv dej kub, thiab tom qab ntawd tsau rau hauv chromic. anhydride los yog poov tshuaj dichromate aqueous tov ntawm 60 mus rau 80 degree nrog ib tug concentration ntawm 2% mus rau 3% rau 5 mus rau 10 feeb, ntxuav nrog ib tug tawv txhuam, ntxuav nrog dej kub, qhuav nyob rau hauv lub qhov cub, los yog tshuab ziab nrog cua kub, los yog qhuav lawm.
