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Isenzakalo esivamile sokugqwala komkhumbi wengcindezi

Njengoba wonke umuntu azi, inzalo iyisitsha sokucindezela esivaliwe, ngokuvamile esenziwe ngensimbi engagqwali noma nge-carbon steel. E-China, kunemikhumbi yokucindezela engaba yizigidi ezingu-2.3 enkonzweni, phakathi kwayo ukugqwala kwensimbi okuvelele ngokukhethekile, okuye kwaba yisithiyo esiyinhloko nemodi yokwehluleka ethinta ukusebenza okuzinzile kwesikhathi eside kwemikhumbi yokucindezela. Njengohlobo lomkhumbi ocindezelayo, ukukhiqizwa, ukusetshenziswa, ukunakekelwa nokuhlolwa kwesibulala-magciwane ngeke kushaywe indiva. Ngenxa yento eyinkimbinkimbi yokugqwala kanye nendlela, amafomu nezici zokugqwala kwensimbi zihlukile ngaphansi kwethonya lezinto ezibonakalayo, izici zemvelo kanye nezimo zokucindezeleka. Okulandelayo, ake sihlole izenzakalo eziningana ezivamile zokugqwala komkhumbi:

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I-1.I-Corrosion Comprehensive (eyaziwa nangokuthi i-uniform corrosion), okuyisenzakalo esibangelwa ukugqwala kwamakhemikhali noma ukugqwala kwe-electrochemical, i-corrosion medium ingafinyelela zonke izingxenye zensimbi ngokulinganayo, ukuze ukwakheka kwensimbi nokuhleleka kube yizimo ezifanayo, yonke indawo yensimbi igqwalile ngesilinganiso esifanayo. Emikhumbini yensimbi engenasici, endaweni ebolayo enenani eliphansi le-PH, ifilimu ye-passivation ingase ilahlekelwe umphumela wayo wokuvikela ngenxa yokonakala, bese kuba nokugqwala okuphelele. Kungakhathaliseki ukuthi ukugqwala okuphelele okubangelwa ukugqwala kwamakhemikhali noma ukugqwala kwe-electrochemical, isici esivamile ukuthi kunzima ukwenza ifilimu yokuvikela i-passivation ebusweni bezinto ngesikhathi senqubo yokugqwala, futhi imikhiqizo yokugqwala ingase incibilike phakathi nendawo, noma yakha i-porous oxide evulekile, eqinisa inqubo yokugqwala. Ukulimala kokugqwala okuphelele akukwazi ukubukelwa phansi: okokuqala, kuzoholela ekunciphiseni indawo yokucindezela yesici esithwala isitsha sokucindezela, okungase kubangele ukuvuza kwe-perforation, noma ukuphuka noma ukuchithwa ngenxa yamandla anganele; Okwesibili, ohlelweni lokugqwala okuphelele kwe-electrochemical, ukusabela kokunciphisa i-H + kuvame ukuhambisana, okungase kubangele ukuthi impahla igcwaliswe nge-hydrogen, bese iholela ku-hydrogen embrittle nezinye izinkinga, okuyisizathu futhi sokuthi kungani imishini idinga ukukhishwa. ngesikhathi sokulungiswa kwe-welding.
2. I-Pitting yinto yendawo yokugqwala eqala phezu kwensimbi futhi inwebe ngaphakathi ukuze yakhe umgodi wokugqwala omise okwembobo encane. Endaweni ethize yezemvelo, ngemva kwesikhathi esithile, izimbobo ezigxilile noma ukugoba kungase kuvele endaweni yensimbi, futhi lezi zimbobo eziqoshiwe zizoqhubeka zikhula ziye ekujuleni ngokuhamba kwesikhathi. Nakuba ukwehla kwesisindo sokuqala sensimbi kungase kube kuncane, ngenxa yezinga elisheshayo lokugqwala kwendawo, imishini nezindonga zamapayipi kuvame ukubhobozwa, okuholela ezingozini ezingazelelwe. Kunzima ukuhlola ukugqwala komgodi ngoba imbobo yomgodi incane ngosayizi futhi ivamise ukumbozwa yimikhiqizo yokugqwala, ngakho kunzima ukukala nokuqhathanisa idigri ye-pitting ngobuningi. Ngakho-ke, ukugqwala komgodi kungabhekwa njengenye yezindlela zokugqwala ezicekela phansi kakhulu futhi ezicashile.
3. I-Intergranular corrosion isenzakalo sendawo sokugqwala esenzeka eduze noma eduze nomngcele wokusanhlamvu, ikakhulukazi ngenxa yomehluko phakathi kwendawo yokusanhlamvu kanye nokwakheka kwamakhemikhali kwangaphakathi, kanye nokuba khona kokungcola komngcele wokusanhlamvu noma ingcindezi yangaphakathi. Nakuba ukugqwala kwe-intergranular kungase kungabonakali ezingeni elikhulu, uma kwenzeka, amandla ezinto ezibonakalayo alahleka cishe ngaso leso sikhathi, ngokuvamile okuholela ekuhlulekeni okungazelelwe kwemishini ngaphandle kwesixwayiso. Ngokujulile, ukugqwala kwe-intergranular kuguqulwa kalula kube ukugqwala kwe-intergranular stress corrosion, okuba umthombo wokuqhekeka kokugqwala kwengcindezi.
4. I-Gap corrosion isenzakalo sokugqwala esenzeka esikhaleni esincane (ububanzi ngokuvamile buba phakathi kuka-0.02-0.1mm) okwakhiwa endaweni yensimbi ngenxa yemizimba yangaphandle noma izizathu zesakhiwo. Lezi zikhala zidinga ukuba zibe mncane ngokwanele ukuvumela uketshezi ukuthi lugeleze futhi lungene, ngaleyo ndlela kunikeze izimo zokuthi igebe ligle. Ekusetshenzisweni okungokoqobo, amajoyinti e-flange, izindawo zokuhlanganisa amantongomane, ama-lap joints, i-weld seams engashiselwanga, imifantu, izimbotshana ezingaphezulu, i-slag yokushisela engahlanjululwanga futhi yafakwa phezu kwensimbi yesikali, ukungcola, njll., kungase kudale izikhala, okuholela ekutheni ukugqwala kwegebe. Lolu hlobo lokugqwala kwendawo luvamile futhi lulimaza kakhulu, futhi lungalimaza ubuqotho bokuxhunywa kwemishini kanye nokucinana kwemishini, okuholela ekuhlulekeni kwemishini ngisho nezingozi ezibhubhisayo. Ngakho-ke, ukuvimbela nokulawula ukugqwala kwemigodi kubaluleke kakhulu, futhi ukugcinwa nokuhlanza imishini njalo kuyadingeka.
5. Ukugqwala kwengcindezi kubala u-49% wengqikithi yezinhlobo zokugqwala zazo zonke iziqukathi, ezibonakala ngomthelela we-synergistic wengcindezi eqondisayo kanye ne-corrosion medium, okuholela ekuqhekekeni okuphukayo. Lolu hlobo lokuqhekeka alukwazi ukuthuthukisa kuphela umngcele wokusanhlamvu, kodwa futhi nokusanhlamvu ngokwawo. Ngokuthuthukiswa okujulile kokuqhekeka ngaphakathi kwensimbi, kuzoholela ekwehleni okukhulu kwamandla esakhiwo sensimbi, futhi ngisho nokwenza imishini yensimbi ilimale ngokuzumayo ngaphandle kwesixwayiso. Ngakho-ke, i-stress corrosion-induced cracking (SCC) inezici zokubhubhisa okungazelelwe futhi okunamandla, uma ukuqhuma kwakhiwa, izinga layo lokunweba lishesha kakhulu futhi asikho isixwayiso esibalulekile ngaphambi kokwehluleka, okuwuhlobo oluyingozi kakhulu lokuhluleka kwemishini. .
6. Isenzakalo sokugcina esivamile sokugqwala ukugqwala kokukhathala, okubhekisela enqubweni yokulimala kancane kancane ebusweni bezinto ezisetshenziswayo kuze kube yilapho kugqashuka ngaphansi kwesenzo esihlanganisiwe sokushintshana kwengcindezi nokugqwala okuphakathi. Umthelela ohlangene wokugqwala kanye nohlobo olushintshayo lwempahla yenza isikhathi sokuqala nezikhathi zomjikelezo zokuqhekeka kokukhathala zibe mfushane ngokusobala, futhi isivinini sokusabalalisa imifantu siyanda, okuphumela ekunciphiseni umkhawulo wokukhathala kwezinto zensimbi. Lesi senzakalo asisheshisi nje kuphela ukwehluleka kokuqala kwesici sokucindezela kwemishini, kodwa futhi kwenza impilo yesevisi yomkhumbi wokucindezela oklanyelwe ngokuvumelana nenqubo yokukhathala ibe ngaphansi kakhulu kunalokho okulindelekile. Enqubweni yokusetshenziswa, ukuze kuvinjelwe izenzakalo ezihlukahlukene zokugqwala njengokugqwala kokukhathala kwemikhumbi yokucindezela yensimbi engagqwali, kufanele kuthathwe izinyathelo ezilandelayo: njalo ngemva kwezinyanga ezingu-6 ukuhlanza ngokuphelele ingaphakathi lethangi lokuvala inzalo, ithangi lamanzi ashisayo nezinye izinto zokusebenza; Uma ubulukhuni bamanzi buphakeme futhi okokusebenza kusetshenziswa amahora angaphezu kwangu-8 ngosuku, kuyahlanzwa njalo ezinyangeni ezi-3.


Isikhathi sokuthumela: Nov-19-2024