Qhov teeb meem ntawm cov hlau corrosion pervades ntau qhov chaw ntawm lub teb chaws kev lag luam, xws li roj thiab roj, petrochemical, tsheb thauj mus los, machinery manufacturing, thiab lwm yam. Corrosion tau coj ntau yam kev puas tsuaj thiab kev puas tsuaj rau kev sib raug zoo.
1. Kev poob nyiaj txiag
Kev poob nyiaj txiag los ntawm corrosion yog staggering. Raws li kev txheeb cais hauv tsev, kev lag luam poob los ntawm kev xeb tau mus txog 280 billion yuan, suav txog li 4 feem pua ntawm tag nrho cov khoom hauv lub tebchaws (GNP). Saib ntawm kev lag luam roj thiab roj thoob ntiaj teb, raws li kev kwv yees ntawm National Association of Corrosion Engineers (NACE), tag nrho lub ntiaj teb txhua xyoo corrosion nqi yog 1.3 billion US dollars, txog 8.6 billion RMB.
2. Kev ua qias tuaj ib puag ncig
Cov pov tseg ntawm cov peev txheej thiab ib puag ncig muaj kuab paug los ntawm corrosion yog qhov hnyav heev. Corrosion tuaj yeem ua rau xeb ntau ntau, ua rau cov khoom siv hlau tsis ua haujlwm ntxov, thiab tseem ua rau cov khoom siv khib nyiab ntau thiab lub zog. Corrosion khoom thiab av yuav txo tau cov cua kub hloov efficiency ntawm boilers, tshav kub exchangers thiab lwm yam khoom, nkim ntau tons ntawm txheem thee. Cov pa phem xws li SO2 tsim los ntawm kev hlawv cov coals no ua rau muaj kev ua qias tuaj ib puag ncig.
3. Kev nyab xeeb txaus ntshai
Nyob rau hauv 2011, ib tug petrochemical nroj tsuag nyob rau hauv lub deethanizer sab saum toj reflux tank ntawm cov roj fractionation chav tsev mam li nco dheev tawg, ua rau 4 tus neeg tuag, 1 raug mob loj, 6 me me raug mob, thiab ib tug ncaj qha nyiaj txiag poob ntawm 8.69 lab yuan. Raws li kev soj ntsuam kev sib tsoo, qhov ua rau muaj kev sib tsoo yog hydrogen sulfide kev nyuaj siab corrosion, uas ua rau lub rupture ntawm reflow tank thiab ua rau tawg.
Hlau Corrosion yog dab tsi?
Cov khoom siv hlau raug puas tsuaj los ntawm kev ua ntawm qhov nruab nrab ib puag ncig, uas yog hu ua hlau corrosion (Metallic Corrosion).
Dab tsi yog hom hlau corrosion?
Vim qhov nyuaj ntawm corrosion phenomena thiab mechanisms, qhov teeb meem thiab cov yam ntxwv ntawm hlau corrosion txawv heev vim qhov sib txawv ntawm cov ntaub ntawv thiab ib puag ncig yam, uas yog, lub xeev kev nyuaj siab. Yog li ntawd, muaj ntau cov qauv kev faib tawm thiab cov txheej txheem, tab sis cov txheej txheem kev faib tawm corrosion feem ntau suav nrog kev faib tawm los ntawm cov txheej txheem corrosion thiab kev faib tawm los ntawm daim ntawv corrosion.
Yuav ua li cas cais raws li corrosion mechanism?
Raws li kev txhim kho corrosion, nws tuaj yeem muab faib ua tshuaj lom neeg corrosion thiab electrochemical corrosion:
Tshuaj corrosion yog hais txog hlau corrosion tshwm sim los ntawm cov tshuaj tiv thaiv ncaj qha ntawm cov hlau thiab tsis-electrolyte.
Electrochemical corrosion yog kev puas tsuaj los ntawm electrochemical kev sib cuam tshuam ntawm hlau thiab electrolyte tov.
Yuav ua li cas cais raws li daim ntawv corrosion?
Raws li kev faib tawm ntawm daim ntawv corrosion, nws tuaj yeem muab faib ua qhov dav dav corrosion thiab localized corrosion:
General corrosion tshwm sim nyob rau hauv tag nrho cov hlau nto thiab tej zaum nws yuav tsis sib xws los yog tsis sib xws.
Localized corrosion yog concentrated nyob rau hauv qee qhov chaw ntawm cov hlau, thaum lwm qhov chaw muaj tsawg los yog tsis muaj corrosion. Muaj ntau hom kev xeb hauv zos, feem ntau muab faib ua pawg hauv qab no:
Galvanic corrosion: Hauv cov tshuaj electrolyte, thaum cov hlau tsis sib xws nyob rau hauv kev sib cuag, cov hlau uas muaj peev xwm ntau dua txhawb cov hlau nrog lub peev xwm qis dua kom nrawm dua corrosion;
Pitting corrosion: Corrosion puas feem ntau yog tsom rau qee cov ntsiab lus nquag, txoj kab uas hla ntawm lub qhov corrosion yog sib npaug los yog me dua qhov tob ntawm lub qhov corrosion, thiab nyob rau hauv qhov hnyav, nws tuaj yeem ua rau cov khoom perforation;
Crevice corrosion: corrosion uas tshwm sim hauv crevices xws li riveting, threaded sib txuas, welded pob qij txha, thiab gaskets;
Intergranular corrosion: Corrosion tshwm sim raws li intergranular, lub zog sib txuas ntawm cov hlau atoms ploj, thiab cov neeg kho tshuab lub zog ntawm cov hlau poob sharply. Feem ntau tsis muaj kev hloov pauv hauv cov tsos ntawm cov hlau ua ntej kev puas tsuaj;
Kev ntxhov siab corrosion: Kev tawg tsis ua haujlwm uas tshwm sim thiab nthuav dav ntawm tus nqi tseem ceeb nyob rau hauv kev sib xyaw ua ke ntawm tensile kev ntxhov siab thiab nruab nrab corrosive; cov hom yog sulfide kev nyuaj siab corrosion cracking thiab hydrogen sulfide kev nyuaj siab corrosion cracking.
Corrosion qaug zog: Corrosion ntawm cov hlau nyob rau hauv qhov kev txiav txim ntawm corrosive media thiab alternating stress.
Yuav ua li cas txo qhov cuam tshuam ntawm corrosion ntawm daim ntawv thov hauv cov txheej txheem thov tiag tiag?
1. Txiav txim seb hom corrosion
Nyob rau hauv daim ntawv thov teb, hom corrosion yog txiav txim raws li hom nruab nrab, siab, kub, ib puag ncig tej yam kev mob thiab corrosion qhov chaw, thiab cov tsim nyog anti-corrosion txoj kev yog xaiv. Piv txwv li, hauv kev lag luam roj thiab roj, cov twj siv yeeb nkab valve qhov chaw thiab cov txheej txheem tseem ceeb ntawm cov kav dej siv cov khoom sib txawv, uas yuav ua rau galvanic corrosion.
2. Xaiv cov khoom tsim nyog corrosion-resistant.
Thaum xaiv cov ntaub ntawv, nws yog ib qho tsim nyog yuav tsum xav txog qhov nruab nrab ntawm cov khoom nruab nrab corrosive, siab thiab ib puag ncig sab nraud. Yog tias ib puag ncig siab tshaj qhov ntsuas kub, nws tsis pom zoo kom siv 316 stainless hlau hauv hiav txwv.
3. Txo txoj hauj lwm qhov twg crevice corrosion yuav tshwm sim.
Txo kev sib cuag nrog cov hlau tsis sib xws. Offshore, qhov kev pheej hmoo ntawm crevice corrosion yog siab thaum hlau tubing thiab hlau raj txhawb nqa siv ua ke. Nws raug pom zoo tias thaum xaiv cov khoom txhawb nqa lub raj, xaiv lub raj txhawb nqa nrog lub gasket.
Corrosion yog ib qho teeb meem kim. Yog tias hom kev xeb thiab qhov chaw ntawm corrosion tuaj yeem txheeb xyuas tau sai, qhov kev pheej hmoo yuav raug txo kom tsawg. Cov kws kho mob uas muaj kev txawj ntse feem ntau tuaj yeem kwv yees qhov twg corrosion yuav tshwm sim, thiab xaiv cov khoom siv hlau tsim nyog ua ntej kom tsis txhob muaj corrosion. Qhov no yuav txhim kho kev ua tau zoo, kev ncaj ncees thiab kev ruaj ntseg ntawm cov tshuab tsim khoom.
