Peb feem ntau xa mus rau cov hlau thov ntawm -10 ~ -196℃raws li "tsawg kub steel", thiab "ultra-low kub steel" siv tsawg dua -196 degree". Tsawg kub steel yuav tsum muaj txaus lub zog, plasticity thiab toughness nyob rau hauv qis kub ua hauj lwm tej yam kev mob, thiab zoo ua hauj lwm nyob rau tib lub sij hawm, feem ntau yog siv rau lub hwj chim, petrochemical, offshore thiab lwm yam lag luam los tsim 5-2℃qhov kub thiab txias cov qauv. kev thauj mus los ntawm txhua hom roj liquefied ntim.
Rau cov yeeb nkab uas tsis kub kub (ASTM A333), feem ntau siv vuam txoj kev yog lo arc vuam, tsis siv neeg submerged arc vuam, tungsten argon arc vuam, thiab roj fusion arc vuam. Lub vuam tam sim no yuav tsum tsis txhob loj dhau. Nyob rau tib lub sijhawm, qhov kub thiab txias ntawm cov welding channel yuav tsum tau tswj. Vuam yuav tsum tau ua nrog me me thiab tswj cov cua kub hauv qab 20KJ / cm.
Weld kab hluav taws xob tseem hu ua vuam cov khoom siv hluav taws xob, uas yog cov cua sov ntawm vuam arc tau txais ib chav tsev ntev ntawm vuam.
Formula: E=U • I / v (joule / cm)
U: arc voltage (volts); I: vuam tam sim no (ampere); V: vuam ceev (cm / min).
Weld kab hluav taws xob yog ib qho tseem ceeb cuam tshuam rau cov khoom siv hluav taws xob ntawm cov yeeb nkab uas tsis tshua muaj hluav taws xob welded pob qij txha. Thaum lub vuam tam sim no thiab arc voltage nce, qhov vuam kab zog nce, nrog rau thaum vuam ceev txo. Rau cov kav dej kub tsis tshua muaj zog, cov vuam kab hluav taws xob loj dhau lawm, qhov sib koom ua ke toughness txo qis sai, uas ua rau lub nkoj siab hauv qhov kub thiab txias ua rau muaj kev puas tsuaj sai sai. Yog li ntawd, lub vuam tam sim no, arc voltage thiab vuam ceev yuav tsum nruj me ntsis tswj.
Tsis tshua muaj kub steel yeeb nkab muaj ib tug me me nyiam hardening thiab ib tug nyiam rau txias cracking vim nws cov ntsiab lus carbon tsawg thiab zoo weldability. Txawm li cas los xij, lub zog vuam ntau dhau yuav ua rau tsim cov qauv siv lead ua tuab nyob rau hauv cov vuam seam thiab tshav kub cuam tshuam rau thaj tsam thiab txo qhov kub tsis tshua muaj zog. Kev hloov pauv ntawm cov qauv thiab lub zog muaj zog hauv kev tsim khoom yuav ua rau muaj kev ntxhov siab hauv zos thiab ua rau cov khoom siv tsis zoo ntawm qhov kub thiab txias. Yog li ntawd, cov lus qhia hauv qab no yuav tsum tau coj mus rau hauv tus account hauv cov txheej txheem vuam:
Cov kab hluav taws xob me me tuaj yeem txo qis cua sov thiab tiv thaiv qhov pom ntawm cov ntaub so ntswg tuab hauv qhov sib txuas. Electrode arc vuam feem ntau siv 12-15kj / cm, thiab submerged arc vuam feem ntau yog 20KJ / cm. Rau lub hom phiaj no, sim zam 5 vuam pas nrig, tsis siv neeg submerged arc vuam ntxiv rau xaiv 3.2 vuam hlau, vuam pas nrig arc vuam txhua txheej ntawm li 2 hli, tsis siv neeg submerged arc vuam txog 2.5 hli.
Ncaj kauj ruam, ntau kauj ruam ceev xovxwm vuam. Nws yog los txo overheating thiab tom qab vuam ntawm pem hauv ntej welding muaj cov nyhuv tempering, thiaj li hais tias cov nplej refinement.
Nws yog ib qho tsim nyog kom tsis txhob muaj zog torque kom tsis txhob muaj kev ntxhov siab hauv zos.
Tus welder yuav tsum txo qhov kub ntawm qhov sib txawv nruab nrab ntawm cov hlaws weld kom ntau li ntau tau, zam cov hlaws hlaws nyob rau hauv qhov kub thiab txias rau lub sijhawm ntev, cov txheej txheem vuam tsis tu ncua yog tsim nyog.
Xaiv cov electrode thiab ultra-low hydrogen flow, ua ntej vuam yuav qhuav raws li qhov yuav tsum tau, cov vuam electrode uas tsis tau siv ntau tshaj 4 teev yuav tsum tau xa rov qab mus rau qhov chaw thib ob kom rov ua kom qhuav thiab siv. Tsis tas li ntawd, qhov kub tsis tshua muaj steel vuam pas nrig rau yuav tsum tau siv raws li cov qauv tsim nyog rau cov hlau diffusion deposition ntawm hydrogen resurvey, feem ntau mercury txoj kev.
Nws yuav tsum tau preheated kom tsawg kawg yog 15 degrees saum toj no. Rau lub caij ntuj no siv los yog tuab-walled steel yeeb nkab, rau vuam loj-phab ntsa tuab steel yeeb nkab, qhov preheating kub feem ntau yog 50 degree, thiab interchannel kub tswj ntawm 50 150 thiab 150 degree.
Arc pib yuav tsum tau ua los ntawm ib tug arc pib phaj los yog nyob rau hauv lub qhov, thiab yuav tsum tsis txhob nqa tawm nyob rau hauv unwelded qhov chaw. Kev ntxhov siab-relieving tshav kub kho tom qab vuam steel kav ntawm qhov kub thiab txias tuaj yeem txo qhov kev pheej hmoo ntawm kev tawg ntawm cov khoom siv hlau tsis tshua muaj hlau.
