Ntev- siv lub sij hawm ntev ntawm stainless hlau cartridge tso cua sov feem ntau ua rau corrosion thiab leaks ntawm welded seams, uas txo cov khoom siv lub neej thiab kev nyab xeeb. Qhov laj thawj tseem ceeb ntawm qhov teeb meem no yog cov khoom siv- cuam tshuam, qhov twg chromium nyob rau hauv stainless hlau reacts nrog carbon thaum lub sij hawm vuam los ua chromium carbides, ua rau "chromium-depleted zones" nyob ze rau lub weld uas txo corrosion kuj; Thaum tshav kub kub- cuam tshuam cheeb tsam (HAZ) cuam tshuam, qhov kub vuam kub hloov pauv microstructure thiab tuaj yeem ua rau cov theem sigma hauv austenitic stainless hlau los yog ua rau tawv tawv hauv martensitic hom, ob qho tib si uas txo cov corrosion kuj; residual stresses los ntawm vuam uas ua rau kom muaj kev ntxhov siab corrosion cracking (SCC); electrochemical corrosion vim muaj qhov tsis zoo xws li qhov pores lossis cov khoom sib xyaw ua ke uas tsim micro-cells uas ua kom nrawm nrawm hauv zos; thiab ib puag ncig xov xwm uas muaj corrosive hais xws li sulfides los yog chloride ions uas nyiam erode welded cheeb tsam.
Ib qho tseem ceeb tshaj plaws ntawm cov txheej txheem vuam kom tsis txhob xeb thiab cov xau yog inert gas shielded vuam (TIG / MIG). Stainless hlau cartridge rhaub tuaj yeem siv Hlau Inert Gas (MIG) lossis Tungsten Inert Gas (TIG). Shielding gas nrog Ar+ thiab siab -purity argon (Ntau dua los yog sib npaug rau 99.99%) tau qhia.Nws muab cov raj nrog cov phab ntsa tuab thiab ntxiv 1-2% hydrogen rau cov ntawv thov tseem ceeb los txhim kho kom zoo. Siv cov cuab yeej tshwj xeeb lossis hauv zos argon filling, backside shielding yog qhov tseem ceeb rau kev tiv thaiv oxidation. Cov txheej txheem hauv qab no yuav tsum tau ua kom zoo dua: vuam ceev ntawm 3-10 cm / min, qhov hluav taws xob ntawm 10-16 V, tam sim no ntawm 60-150 A (nyob ntawm txoj kab uas hla ntawm lub raj), thiab siv cov tam sim no qis thiab ceev ceev kom txo cov cua sov nkag.
High automation nrog meej, repeatable tsis zoo tagnrho rau ntau lawm; tsis xav tau muab tub lim, tiv thaiv galvanic corrosion los ntawm cov hlau sib txawv; HAZ qis (tsuas yog 1/3-1/5 ntawm cov txheej txheem ib txwm muaj), txo qis chromium depletion; thiab qhov tob tob -rau-dav piv rau qhov nqaim, sib sib zog nqus welds uas txo qhov cuam tshuam rau corrosive media yog qee qhov txiaj ntsig ntawm laser vuam rau precision cartridge rhaub pob qij txha.
Welding sequences zoo li symmetrical los yog segmented backstepping txo qhov seem seem; post-weld kev kho mob rau cov khoom tseem ceeb muaj xws li tshuaj annealing (1050-1100℃ceev quench) los yog stabilization (850-930℃tuav); interpass kub hauv qab 150℃rau ntau txheej welds kom tsis txhob intergranular corrosion-rhiab ntau yam (450-850 degree); thiab cua sov input txwv rau 5-15 kJ / cm kom tiv thaiv overheating.
Thawj kauj ruam hauv kev txhawb nqa cov txheej txheem tswj kom zoo yog cov khoom siv ua ntej, uas suav nrog txhuam cov hlau tsis huv kom tshem tawm cov oxides thiab ntxuav lub ntsej muag nrog acetone lossis lwm yam tshuaj tshwj xeeb kom tshem tawm cov roj. U- lossis V-zoo li zawj tsim nrog 60-80℃kaum sab xis thiab 0.5-1 hli blunt npoo yog pom zoo. Siv khiav- rau thiab khiav- tawm tab los tiv thaiv arcing ncaj qha ntawm cov khoom ua haujlwm thaum vuam; xyuas kom cov vuam txuas ntxiv, txias maj mam yog tias nws cuam tshuam; thiab siv stainless hlau txhuam rau interpass tu. Cov txheej txheem tom qab vuam muaj xws li acid pickling nrog nitric-hydrofluoric ua ke thiab nitric passivation; electrolytic polishing ntxiv txhim kho corrosion kuj; thiab kev vibration aging, txhaj tshuaj peening, los yog kev kho cua sov kom txo tau cov kev ntxhov siab seem.
High -chloride chaw, xws li kev siv ultra- cov qib qis carbon zoo li 00Cr17Ni14Mo2, molybdenum- muaj cov fillers zoo li ER316L, thiab xav tau kev kho mob ntxiv rau pickling -passivation, yog kev hloov kho rau tej yam kev mob. Tag nrho- nkag hauv paus vuam los tiv thaiv tsis muaj{11}} ntawm- fusion; tag nrho- txoj haujlwm txoj haujlwm; thiab npib tsib xee-raws li cov fillers, xws li ERNiCrMo{19}}3, rau kev ua tau zoo ntawm qhov kub thiab txias. Tswj weld reinforcement rau 0.5-1.5 mm rau seamless hloov nyob rau hauv alternating loads; preheat low-hydrogen fillers rau 100-150℃rau kev puas tsuaj.
Kev soj ntsuam zoo thiab kev soj ntsuam cov txheej txheem suav nrog tsis yog - kev kuaj kev puas tsuaj (PT rau qhov chaw tsis xws luag, RT lossis UT rau sab hauv, thiab helium huab hwm coj spectrometry rau cov khoom nqus tsev); kev ntsuam xyuas corrosion (10% oxalic acid etch rau sigma theem, 65% nitric acid boil rau intergranular susceptibility, thiab ntsev tsuag rau tag nrho cov kuj); Kev ntsuam xyuas txhua yam (microhardness rau HAZ tswj, khoov rau plasticity, thiab hydrostatic ntawm 1.5 npaug ntawm kev ua haujlwm siab).
Nyob rau hauv xaus, ib tug txheej txheem welding txheej txheem yog tsim nyog los nres corrosion thiab to ntawm welds nyob rau hauv stainless hlau cartridge heaters. Laser ua haujlwm zoo nyob rau hauv siab -xav tau qhov xwm txheej, thaum TIG/MIG nrog kev tswj nruj dua yog pheej yig dua. Kev tswj cov khoom siv hluav taws xob, tiv thaiv, thiab tom qab- kev kho vuam yog qhov tseem ceeb tsis hais txog txheej txheem. Txhawm rau lav ntev -lub sij hawm corrosion kuj ntawm cov pob qij txha, kho qhov tsis zoo rau cov xwm txheej ua haujlwm thiab teeb tsa cov txheej txheem tshuaj xyuas kom ntseeg tau.
