Dab tsi ua rau irreversible pitting ntawm welds ntawm 316 stainless hlau cua sov raj?

# Dab tsi yog qhov ua rau irreversible pitting ntawm welds ntawm 316 stainless hlau cua sov raj? Cov vuam fissures yog qhov chaw uas muaj kev cuam tshuam tshaj plaws rau irreversible pitting corrosion nyob rau hauv fermentation ntau lawm, txawm lub fact tias 316 stainless hlau cua sov raj cia siab rau ib tug chromium - nplua nuj passive zaj duab xis rau anti- corrosion tiv thaiv. Nws yog tsis yooj yim sua kom tshem tawm cov pits uas tau tsim nyob rau hauv weld cheeb tsam los ntawm yooj yim passivation, thiab lawv yuav nce zuj zus mus tsim los ntawm - phab ntsa to, uas ua rau nruab nrab muaj kuab paug thiab tsis tau npaj txhij kaw. Cov txheej tiv thaiv ntawm welds yuav raug rhuav tshem los ntawm kev sib xyaw ua ke, kev ua haujlwm, thiab kev saib xyuas yam tseem ceeb. Cov lus uas muaj nyob hauv categorises cov tseem ceeb inducing yam thiab lawv cov theem txaus ntshai.|Inducing Factor|Tshwj xeeb tshwm sim ntawm Welds|Degree ntawm Pitting Risk|Kev tswj xyuas zoo|| ----|----|----|----|----|| Tsis tiav argon rov qab tiv thaiv thaum vuam|Oxidation dub oxide txheej hauv weld seam|Siab heev|Tswj tag nrho argon tiv thaiv thiab tom qab vuam polishing|| Alkali ntxuav kub tshaj 60 degree|Passive zaj duab xis instant zos tawg|Siab|Xauv PLC cuam tshuam los txiav fais fab saum 60 degree|| Ntev mus ntev nruab nrab chloride tshaj 50ppm|Chloride penetrates zaj duab xis qhov sib txawv los tsim micro-pits|Siab|Nruab online chloride saib xyuas lub sijhawm|| Unpolished ntxhib weld nto|Cov av thiab cov organic teeb meem tso rau hauv cov kab mob corrosion|Nruab nrab|Tag nrho cov neeg kho tshuab polishing rau tag nrho cov vuam pob qij txha|| Tsis nco qab-weld hauv zos passivation|Weld cheeb tsam tsis ntom chromium zaj duab xis|Nruab nrab|Supplementary pickling passivation tom qab vuam|| Sib tov sib cuag nrog liab qab carbon steel brackets|Galvanic corrosion accelerates qhov nthuav dav|Nruab nrab|Tso tag PTFE cais strips|Weld pitting pib los ntawm kev puas tsuaj ntawm cov yeeb yaj kiab tsis tu ncua. Tom qab kub-kub melting thiab txias, lub puab grain qauv ntawm welding pob qij txha undergoes ib tug tseem ceeb transformation, uas ua rau ib tug passive zaj duab xis uas yog yooj yim dua thiab nyias dua li lub hauv paus yeeb nkab lub cev. Oxygen yuav hnov ​​​​mob nrog cov ntsiab lus hlau nyob hauv qhov vuam los tsim cov txheej oxide xoob yog tias cov tuam txhab tsis saib xyuas argon rov qab tiv thaiv thaum ua haujlwm. Cov khaubncaws sab nraud povtseg tsis tuaj yeem tsim muaj kev tiv thaiv tag nrho, txawm tias tom qab tag nrho cov raj tau dhau los lawm. Tom qab lub limtiam ntawm cyclic cleansing, micro-pits tsim los ntawm lub ntuj infiltration ntawm chloride thiab alkaline kua los ntawm cov me me nyob rau hauv lub oxide txheej. Lwm qhov txiaj ntsig tseem ceeb yog kev siv qhov kub thiab txias alkaline CIP tu. Thaum qhov kub ntawm alkali kua tshaj 60 degrees CelsiusHydroxide ions yuav sai sai yaj cov chromium oxide zaj duab xis ntawm weld nto ntawm ib tug kub ntawm degree. Electrochemical corrosion cells yog tsim tam sim ntawd thaum chloride nyob rau hauv nruab nrab. Nyob rau hauv ob peb lub voj voog ntau lawm, cov qhov ntiav ntiav hloov mus rau hauv qhov tob, qhov tsis tuaj yeem rov qab tau. Nyob rau hauv sib piv rau cov txheej saum npoo xeb, pitting yog tus cwj pwm los ntawm cov ntsiab lus ntawm cov ntsiab lus me me uas zais hauv qab grime thiab nyuaj rau txheeb xyuas thaum ua haujlwm txhua hnub. Tib txoj kev uas tuaj yeem ntes tau qhov chaw nkaum thinning weld ua ntej yog ob lub hlis ultrasonic phab ntsa thickness scanning. Fermentation organic residues yuav raug daig los ntawm qhov ntxhib, tsis muaj qhov sib txuas, uas yuav decompose los tsim cov tshuaj acidic thiab ntxiv erode cov zaj duab xis passive. Weld refining thiab hauv zos post-weld passivation feem ntau raug tshem tawm los ntawm cov chaw tsim khoom me me txhawm rau txo cov nqi, uas ua rau cov weld pitting thaum ntxov hauv thawj xyoo ntawm kev ua haujlwm. Txhawm rau tiv thaiv qhov tshwm sim ntawm qhov tsis xws luag, kev yuav khoom cov kev qhia tshwj xeeb yuav tsum tau hais meej meej tag nrho weld refining thiab thib ob hauv zos passivation. Cais tag nrho cov pa roj carbon steel txhawb nqa nrog PTFE cov ntaub ntawv thiab nruj me ntsis tswj qhov kub thiab chloride cov ntsiab lus ntawm alkali ntxuav thaum ua haujlwm txhua hnub. Weld pitting tuaj yeem ua tau zoo ncua sijhawm, kev pab cuam lub neej ntawm 316 stainless hlau cua sov raj tuaj yeem txuas ntxiv, thiab kev xau sai sai hauv kev tsim khoom tuaj yeem tiv thaiv tau los ntawm kev tshawb pom ntawm phab ntsa tuab thiab ntxiv passivation.