Corrosion yog ib qho ntawm cov yam tseem ceeb tshaj plaws uas ua rau muajlub valvekev puas tsuaj. Yog li ntawd, nyob rau hauvlub valvekev tiv thaiv, valve tiv thaiv xeb yog qhov teeb meem tseem ceeb uas yuav tsum xav txog.
Lub qhov dejdaim ntawv xeb
Qhov xeb ntawm cov hlau feem ntau yog tshwm sim los ntawm kev xeb tshuaj lom neeg thiab kev xeb hluav taws xob, thiab kev xeb ntawm cov khoom siv tsis yog hlau feem ntau yog tshwm sim los ntawm kev ua haujlwm tshuaj lom neeg thiab lub cev ncaj qha.
1. Kev xeb tshuaj lom neeg
Nyob rau hauv qhov xwm txheej uas tsis muaj tam sim no tsim tawm, cov khoom nruab nrab ib puag ncig ncaj qha cuam tshuam nrog cov hlau thiab rhuav tshem nws, xws li kev xeb ntawm cov hlau los ntawm cov roj qhuav kub thiab cov tshuaj tsis-electrolytic.
2. Kev xeb galvanic
Cov hlau sib cuag nrog cov electrolyte, ua rau muaj cov electrons ntws, uas ua rau nws tus kheej raug puas tsuaj los ntawm kev ua electrochemical, uas yog hom tseem ceeb ntawm kev xeb.
Kev xeb ntawm cov kua qaub-raws ntsev, kev xeb ntawm huab cua, kev xeb ntawm av, kev xeb ntawm dej hiav txwv, kev xeb ntawm cov kab mob me me, kev xeb ntawm qhov chaw thiab kev xeb ntawm cov hlau tsis xeb, thiab lwm yam, yog txhua yam kev xeb los ntawm hluav taws xob. Kev xeb los ntawm hluav taws xob tsis yog tsuas yog tshwm sim ntawm ob yam khoom uas tuaj yeem ua lub luag haujlwm tshuaj lom neeg xwb, tab sis kuj tsim cov qhov sib txawv ntawm qhov sib txawv ntawm cov tshuaj, qhov sib txawv ntawm cov pa oxygen nyob ib puag ncig, qhov sib txawv me ntsis ntawm cov qauv ntawm cov khoom, thiab lwm yam, thiab tau txais lub zog ntawm kev xeb, yog li cov hlau uas muaj peev xwm qis thiab qhov chaw ntawm lub phaj qhuav ploj mus.
Tus nqi xeb ntawm lub valve
Tus nqi ntawm kev xeb tuaj yeem faib ua rau qib:
(1) Tiv thaiv xeb tag nrho: tus nqi xeb tsawg dua 0.001 hli / xyoo
(2) Tiv taus xeb heev: tus nqi xeb 0.001 txog 0.01 hli / xyoo
(3) Kev tiv thaiv xeb: tus nqi xeb 0.01 txog 0.1 hli / xyoo
(4) Tseem tiv taus xeb: tus nqi xeb 0.1 txog 1.0 hli / xyoo
(5) Kev tiv thaiv xeb tsis zoo: tus nqi xeb 1.0 txog 10 hli / xyoo
(6) Tsis tiv taus xeb: tus nqi xeb ntau dua 10 hli / xyoo
Cuaj txoj kev tiv thaiv xeb
1. Xaiv cov khoom siv tiv taus xeb raws li cov khoom siv corrosive
Hauv qhov tseeb ntau lawm, qhov xeb ntawm cov khoom nruab nrab yog qhov nyuaj heev, txawm tias cov khoom siv valve siv rau hauv tib lub khoom nruab nrab yog tib yam, qhov concentration, kub thiab siab ntawm cov khoom nruab nrab yog txawv, thiab qhov xeb ntawm cov khoom nruab nrab rau cov khoom tsis zoo ib yam. Rau txhua 10 ° C nce hauv qhov kub nruab nrab, qhov xeb nce ntxiv li 1 ~ 3 zaug.
Qhov nruab nrab concentration muaj feem cuam tshuam loj heev rau qhov corrosion ntawm cov khoom siv valve, xws li cov hlau lead nyob hauv sulfuric acid nrog qhov concentration me me, qhov corrosion yog me heev, thiab thaum qhov concentration tshaj 96%, qhov corrosion nce siab heev. Cov hlau carbon, ntawm qhov tsis sib xws, muaj qhov corrosion loj tshaj plaws thaum qhov concentration sulfuric acid yog li 50%, thiab thaum qhov concentration nce mus txog ntau dua 60%, qhov corrosion txo qis heev. Piv txwv li, txhuas yog corrosive heev hauv concentrated nitric acid nrog qhov concentration ntau dua 80%, tab sis nws yog corrosive heev hauv nruab nrab thiab qis concentration ntawm nitric acid, thiab stainless hlau yog heev resistant rau dilute nitric acid, tab sis nws yog aggravated hauv ntau dua 95% concentrated nitric acid.
Los ntawm cov piv txwv saum toj no, nws tuaj yeem pom tias qhov kev xaiv cov khoom siv valve kom raug yuav tsum yog raws li qhov xwm txheej tshwj xeeb, tshuaj xyuas ntau yam uas cuam tshuam rau kev xeb, thiab xaiv cov ntaub ntawv raws li phau ntawv qhia tiv thaiv kev xeb.
2. Siv cov khoom siv uas tsis yog hlau
Kev tiv thaiv xeb uas tsis yog hlau yog qhov zoo heev, tsuav yog qhov kub thiab siab ntawm lub valve ua tau raws li qhov yuav tsum tau ua ntawm cov khoom siv tsis yog hlau, nws tsis tsuas yog daws tau qhov teeb meem xeb, tab sis kuj txuag tau cov hlau muaj nqis. Lub cev valve, lub kaus mom, txheej, qhov chaw kaw thiab lwm yam khoom siv tsis yog hlau uas siv ntau yog ua.
Cov yas xws li PTFE thiab chlorinated polyether, nrog rau roj hmab ntuj, neoprene, roj hmab nitrile thiab lwm yam roj hmab siv rau hauv lub valve, thiab lub cev tseem ceeb ntawm lub valve lub cev bonnet yog ua los ntawm cov hlau cam khwb cia thiab cov hlau carbon. Nws tsis tsuas yog ua kom lub valve muaj zog xwb, tab sis kuj ua kom lub valve tsis xeb.
Niaj hnub nim no, ntau thiab ntau cov yas xws li nylon thiab PTFE siv, thiab roj hmab ntuj thiab roj hmab hluavtaws siv los ua ntau yam kev sib khi thiab cov nplhaib sib khi, uas siv rau ntau yam li qub. Cov ntaub ntawv tsis yog hlau no siv ua cov chaw sib khi tsis yog tsuas yog muaj kev tiv thaiv corrosion zoo xwb, tab sis kuj muaj kev ua tau zoo sealing, uas yog qhov tshwj xeeb tshaj yog rau kev siv hauv cov xov xwm nrog cov khoom me me. Tau kawg, lawv tsis muaj zog thiab tiv taus cua sov, thiab ntau yam kev siv yog txwv.
3. Kev kho qhov chaw hlau
(1) Kev sib txuas ntawm lub valve: Lub qhov txuas ntawm lub valve feem ntau yog kho nrog galvanizing, chrome plating, thiab oxidation (xiav) los txhim kho lub peev xwm los tiv taus atmospheric thiab nruab nrab corrosion. Ntxiv rau cov txheej txheem saum toj no, lwm cov fasteners kuj raug kho nrog kev kho saum npoo xws li phosphating raws li qhov xwm txheej.
(2) Kev sib khi ntawm qhov chaw thiab qhov chaw kaw nrog lub cheeb me me: cov txheej txheem nto xws li nitriding thiab boronizing yog siv los txhim kho nws txoj kev tiv thaiv corrosion thiab hnav tsis kam.
(3) Qia tiv thaiv xeb: nitriding, boronization, chrome plating, nickel plating thiab lwm yam kev kho mob nto yog siv dav los txhim kho nws txoj kev tiv thaiv corrosion, corrosion tsis kam thiab abrasion tsis kam.
Kev kho qhov chaw sib txawv yuav tsum tsim nyog rau cov khoom siv qia sib txawv thiab qhov chaw ua haujlwm, nyob rau hauv huab cua, dej pa nruab nrab thiab asbestos packing contact qia, tuaj yeem siv cov txheej txheem chrome nyuaj, cov txheej txheem roj nitriding (cov hlau tsis xeb yuav tsum tsis txhob siv cov txheej txheem ion nitriding): nyob rau hauv hydrogen sulfide atmospheric ib puag ncig siv electroplating siab phosphorus nickel txheej muaj kev ua tau zoo dua kev tiv thaiv; 38CrMOAIA kuj tseem tuaj yeem tiv taus corrosion los ntawm ion thiab roj nitriding, tab sis cov txheej txheem chrome nyuaj tsis haum rau kev siv; 2Cr13 tuaj yeem tiv taus ammonia corrosion tom qab quenching thiab tempering, thiab cov hlau carbon siv roj nitriding kuj tuaj yeem tiv taus ammonia corrosion, thaum txhua cov txheej phosphorus-nickel plating tsis tiv taus ammonia corrosion, thiab cov khoom siv roj nitriding 38CrMOAIA muaj kev tiv thaiv corrosion zoo heev thiab kev ua tau zoo, thiab nws feem ntau yog siv los ua valve stems.
(4) Lub cev me me thiab lub log tes: Nws kuj feem ntau yog chrome-plated los txhim kho nws txoj kev tiv thaiv corrosion thiab kho kom zoo nkauj lub valve.
4. Kev txau tshuaj thermal
Kev txau thermal yog ib hom txheej txheem rau kev npaj cov txheej txheem, thiab tau dhau los ua ib qho ntawm cov thev naus laus zis tshiab rau kev tiv thaiv cov khoom siv nto. Nws yog ib txoj kev ua kom lub ntsej muag muaj zog uas siv cov cua sov muaj zog (pa roj hlawv, hluav taws xob arc, plasma arc, hluav taws xob cua sov, roj tawg, thiab lwm yam) los ua kom sov thiab yaj cov hlau lossis cov khoom tsis yog hlau, thiab txau rau ntawm qhov chaw ua ntej ua ntej hauv daim ntawv ntawm atomization los ua ib txheej txau, lossis ua kom lub ntsej muag muaj zog tib lub sijhawm, kom txheej txheej yaj dua rau ntawm qhov chaw ntawm lub substrate los ua ib txheej txau vuam kom muaj zog nto.
Feem ntau cov hlau thiab lawv cov alloys, hlau oxide ceramics, cermet composites thiab cov hlau tawv sib xyaw tuaj yeem coated rau ntawm cov hlau lossis cov hlau tsis yog hlau los ntawm ib lossis ntau txoj kev thermal spraying, uas tuaj yeem txhim kho qhov corrosion tsis kam, hnav tsis kam, kub tsis kam thiab lwm yam khoom, thiab ntev lub neej kev pabcuam. Thermal spraying tshwj xeeb functional txheej, nrog rau kev rwb thaiv tsev kub, rwb thaiv tsev (lossis hluav taws xob tsis zoo), grindable sealing, self-lubrication, thermal radiation, electromagnetic shielding thiab lwm yam khoom tshwj xeeb, kev siv thermal spraying tuaj yeem kho qhov chaw.
5. Tshuaj tsuag xim
Kev txheej yog ib txoj kev tiv thaiv xeb uas siv dav dav, thiab nws yog ib qho khoom siv tiv thaiv xeb thiab cim qhia txog cov khoom siv valve. Kev txheej kuj yog ib yam khoom siv uas tsis yog hlau, feem ntau yog ua los ntawm cov roj hmab hluavtaws, cov roj hmab slurry, roj zaub, cov kuab tshuaj, thiab lwm yam, npog cov hlau nto, cais cov khoom nruab nrab thiab huab cua, thiab ua tiav lub hom phiaj ntawm kev tiv thaiv xeb.
Cov txheej txheem feem ntau yog siv rau hauv dej, dej ntsev, dej hiav txwv, huab cua thiab lwm yam ib puag ncig uas tsis xeb dhau. Lub qhov sab hauv ntawm lub valve feem ntau yog pleev xim nrog cov xim tiv thaiv xeb kom tiv thaiv dej, cua thiab lwm yam xov xwm los ntawm kev xeb lub valve.
6. Ntxiv cov tshuaj tiv thaiv xeb
Lub tshuab uas cov tshuaj tiv thaiv xeb tswj kev xeb yog tias nws txhawb nqa qhov polarization ntawm lub roj teeb. Cov tshuaj tiv thaiv xeb feem ntau yog siv rau hauv cov xov xwm thiab cov khoom sau. Kev ntxiv cov tshuaj tiv thaiv xeb rau hauv nruab nrab tuaj yeem ua rau qeeb qhov xeb ntawm cov khoom siv thiab cov li qub, xws li chromium-nickel stainless hlau hauv cov pa oxygen-free sulfuric acid, qhov ntau ntawm solubility loj mus rau hauv lub xeev cremation, xeb yog qhov hnyav dua, tab sis ntxiv me ntsis ntawm tooj liab sulfate lossis nitric acid thiab lwm yam oxidants, tuaj yeem ua rau cov hlau stainless hloov mus rau hauv lub xeev blunt, qhov chaw ntawm ib daim zaj duab xis tiv thaiv kom tiv thaiv kev yaig ntawm cov xov xwm, hauv hydrochloric acid, yog tias ntxiv me ntsis ntawm oxidant, qhov xeb ntawm titanium tuaj yeem txo qis.
Kev ntsuas siab ntawm lub valve feem ntau yog siv los ua qhov nruab nrab rau kev ntsuas siab, uas yooj yim ua rau xeb ntawmlub valve, thiab ntxiv me ntsis sodium nitrite rau hauv dej tuaj yeem tiv thaiv kev xeb ntawm lub valve los ntawm dej. Asbestos packing muaj chloride, uas ua rau lub valve qia xeb heev, thiab cov ntsiab lus chloride tuaj yeem txo qis yog tias siv txoj kev ntxuav dej kub, tab sis txoj kev no nyuaj heev rau kev siv, thiab tsis tuaj yeem nrov npe dav dav, thiab tsuas yog haum rau cov kev xav tau tshwj xeeb.
Yuav kom tiv thaiv lub valve qia thiab tiv thaiv kev xeb ntawm cov asbestos packing, hauv cov asbestos packing, cov tshuaj tiv thaiv xeb thiab cov hlau txi tau coated rau ntawm lub valve qia, cov tshuaj tiv thaiv xeb yog tsim los ntawm sodium nitrite thiab sodium chromate, uas tuaj yeem tsim cov zaj duab xis passivation ntawm qhov chaw ntawm lub valve qia thiab txhim kho qhov kev tiv thaiv xeb ntawm lub valve qia, thiab cov kuab tshuaj tuaj yeem ua rau cov tshuaj tiv thaiv xeb maj mam yaj thiab ua lub luag haujlwm lubricating; Qhov tseeb, zinc kuj yog cov tshuaj tiv thaiv xeb, uas tuaj yeem ua ke nrog chloride hauv asbestos ua ntej, yog li chloride thiab cov hlau qia sib cuag tau txo qis heev, yog li ua tiav lub hom phiaj ntawm kev tiv thaiv xeb.
7. Kev tiv thaiv hluav taws xob
Muaj ob hom kev tiv thaiv electrochemical: kev tiv thaiv anodic thiab kev tiv thaiv cathodic. Yog tias zinc siv los tiv thaiv hlau, zinc raug xeb, zinc hu ua hlau sacrificial, hauv kev xyaum tsim khoom, kev tiv thaiv anode siv tsawg dua, kev tiv thaiv cathodic siv ntau dua. Txoj kev tiv thaiv cathodic no yog siv rau cov li qub loj thiab cov li qub tseem ceeb, uas yog txoj kev pheej yig, yooj yim thiab ua tau zoo, thiab zinc ntxiv rau cov asbestos packing los tiv thaiv lub valve stem.
8. Tswj qhov chaw muaj kuab paug
Ib puag ncig hu ua muaj ob hom kev nkag siab dav thiab kev nkag siab nqaim, kev nkag siab dav ntawm ib puag ncig hais txog ib puag ncig nyob ib puag ncig qhov chaw teeb tsa lub valve thiab nws cov khoom siv sab hauv, thiab kev nkag siab nqaim ntawm ib puag ncig hais txog cov xwm txheej nyob ib puag ncig qhov chaw teeb tsa lub valve.
Feem ntau ib puag ncig tsis tuaj yeem tswj tau, thiab cov txheej txheem tsim khoom tsis tuaj yeem hloov pauv tau. Tsuas yog thaum tsis muaj kev puas tsuaj rau cov khoom thiab cov txheej txheem, txoj kev tswj hwm ib puag ncig tuaj yeem siv tau, xws li deoxygenation ntawm dej boiler, ntxiv alkali hauv cov txheej txheem refining roj kom kho tus nqi PH, thiab lwm yam. Los ntawm qhov kev xav no, kev ntxiv cov tshuaj tiv thaiv corrosion thiab kev tiv thaiv electrochemical hais saum toj no kuj yog ib txoj hauv kev los tswj hwm ib puag ncig corrosive.
Cov huab cua puv nrog hmoov av, dej pa thiab pa luam yeeb, tshwj xeeb tshaj yog nyob rau hauv qhov chaw tsim khoom, xws li cov pa luam yeeb brine, cov pa lom thiab cov hmoov me me uas cov khoom siv tso tawm, uas yuav ua rau muaj ntau qib ntawm kev xeb rau lub valve. Tus neeg teb xov tooj yuav tsum tsis tu ncua ntxuav thiab ntxuav lub valve thiab rov ua kom roj tsis tu ncua raws li cov kev cai ntawm cov txheej txheem ua haujlwm, uas yog ib qho kev ntsuas zoo los tswj kev xeb ib puag ncig. Kev teeb tsa lub hau tiv thaiv ntawm lub valve qia, teeb tsa lub qhov av rau ntawm lub valve hauv av, thiab txau xim rau ntawm qhov chaw ntawm lub valve yog txhua txoj hauv kev los tiv thaiv cov tshuaj corrosive los ntawm kev lwj.lub valve.
Qhov nce ntawm qhov kub thiab txias thiab huab cua ua pa phem, tshwj xeeb tshaj yog rau cov khoom siv thiab cov li qub hauv qhov chaw kaw, yuav ua rau lawv xeb sai dua, thiab cov chaw ua haujlwm qhib lossis cov cua thiab cua txias yuav tsum siv ntau li ntau tau kom qeeb qhov xeb ib puag ncig.
9. Txhim kho cov txheej txheem ua haujlwm thiab cov qauv valve
Kev tiv thaiv corrosion ntawm cov khoom sivlub valveyog ib qho teeb meem uas tau xav txog txij thaum pib tsim, thiab cov khoom siv valve nrog kev tsim qauv tsim nyog thiab txoj kev ua haujlwm raug yuav muaj qhov cuam tshuam zoo rau kev qeeb qeeb ntawm kev xeb ntawm lub valve. Yog li ntawd, lub chaw tsim qauv thiab chaw tsim khoom yuav tsum txhim kho cov khoom uas tsis tsim nyog hauv kev tsim qauv, tsis raug hauv cov txheej txheem thiab yooj yim ua rau xeb, kom hloov kho lawv rau qhov xav tau ntawm ntau yam kev ua haujlwm.
Lub sijhawm tshaj tawm: Lub Ib Hlis-22-2025
