Valves tswj cov kua hauv cov txheej txheem kav dej. Kev xaiv cov khoom siv tsis raug ua rau cov dej xau, cov neeg kho tshuab qaug dab peg, lossis teeb meem kev nyab xeeb hnyav. Cov kws kho tsheb yuav tsum sib phim cov ntaub ntawv kom meej rau cov kev ua haujlwm nyuaj uas muaj cov kua qaub muaj zog, alkalis, qhov kub thiab txias.
Yam khoom siv hauv paus
Valve cov ntaub ntawv poob rau hauv tsib pawg thawj. Economical carbon steels muaj lub zog siab. Stainless hlau muab kev tiv thaiv corrosion. Alloy steels withstand kub thiab siab. Cov alloys tshwj xeeb tiv taus qhov chaw corrosive heev. Tsis yog- metallics xa cov tshuaj tiv thaiv zoo tshaj.
Kev siv carbon steel
Cov pa roj carbon steel yog cov khoom siv hauv lub cev feem ntau vim yog tus nqi -kev ua tau zoo.
WCB cam khwb cia steel suits tsis yog -corrosive media xws li dej, chav, thiab roj nyob rau hauv ib tug -29℃mus rau 425℃ntau yam.
WCC muab kev sib txuas zoo dua los ntawm cov ntsiab lus qis dua.
LCB suav nrog npib tsib xee los txhim kho qis -kub toughness mus rau -46℃.
Cov pa roj carbon steel tsis muaj kev tiv thaiv corrosion thiab yuav tsum tsis txhob siv rau hauv cov kev pabcuam corrosive.
Stainless hlau yam ntxwv
Stainless steels muab zoo heev corrosion kuj.
Qib 304 resists oxidizing acids tab sis raug kev txom nyem pitting hauv chloride ib puag ncig.
Qib 316 muaj molybdenum los txhim kho chloride-induced corrosion resistance rau seawater cov kev pab cuam.
Qib 316L muaj ultra- qis-carbon muaj pes tsawg leeg rau superior intergranular corrosion kuj.
Qib 321 siv titanium stabilization rau siab - kev siv kub txog li 900℃.
Alloy Steel Performance
Alloy steels siv feem ntau hauv siab - cov kev pabcuam parameter.
WC6 muab kev pabcuam ntev - mus txog 595℃nrog rau nruab nrab hydrogen nres tsis kam.
WC9 muab siab dua -kub lub zog rau supercritical chav tshuab.
Qib C5 thiab C12 muaj cov ntsiab lus siab chromium rau tshwj xeeb oxidation thiab sulfidation kuj nyob rau hauv qhov xav tau ib puag ncig.
Tshwj xeeb Alloy Solutions
Tshwj xeeb alloys nyob twj ywm irreplaceable rau huab corrosive tej yam kev mob.
Hastelloy tiv taus txhua yam tshuaj phem heev.
Monel alloys muaj qhov tshwj xeeb tiv thaiv dej hiav txwv thiab hydrofluoric acid.
Titanium alloys nthuav tawm ze rau - pes tsawg corrosion nyob rau hauv dej hiav txwv tab sis ua rau muaj hluav taws kub hnyav nyob rau hauv cov pa ntshiab ntshiab.
PTFE-lined li qub tiv taus yuav luag txhua cov kua qaub uas muaj zog txawm tias qhov kub thiab txias qis dua 180℃.
Kev Xaiv Engineering
Cov tswv yim engineering yuav tsum muaj qhov sib piv qhov tseeb. Concentrated sulfuric acid tsim ib txheej passive ntawm carbon steel, rendering nws preferable rau stainless hlau. Hydrochloric acid nruj me ntsis thov Hastelloy B lossis Monel. Cov roj chlorine qhuav tso cai rau kev siv cov pa roj carbon steel thaum ntub cov tshuaj chlorine yuav tsum tau titanium. Saturated chav tso cai rau WCB qhov chaw superheated chav yuav tsum tau hloov kho dua tshiab rau WC6 lossis WC9. Tsawg- qhov kub thiab txias yog tsom rau kev tiv thaiv kev puas tsuaj. Cov pa roj carbon zoo tib yam yog txwv tsis pub qis dua -29℃. Cov kev pabcuam Cryogenic tswj hwm austenitic stainless hlau txhawb nqa los ntawm Charpy cuam tshuam kev kuaj. Oxygen pipelines yuav tsum nruj degreasing thiab txwv tsis pub titanium. Cov kab kua chlorine kiag li txwv tsis pub tooj liab alloys. Valve internals hais tias sealing kev ua tau zoo. Trim metallurgy yuav tsum sib phim lossis tshaj lub cev lub cev, feem ntau siv Stellite nyuaj-ntsig.
Tus nqi Optimization thiab Common Pitfalls
Kev xaiv cov khoom siv yuav tsum sib npaug cov nqi ntawm lub neej yam tsis muaj qhov muag tsis pom kev nrhiav qib hwm. Concentrated sulfuric acid yog zoo dua los ntawm carbon steel dua stainless hlau. Cov kws ua choj yuav tsum zam qhov tsis zoo. Cov lus dab neeg ntawm stainless hlau universality ignores sai degradation nyob rau hauv HCl thiab kub concentrated alkalis. Piv txwv tias qib siab dua muaj kev nyab xeeb zoo dua ua rau cov peev nyiaj pov tseg. Tsis quav ntsej qhov kub thiab txias los hloov cov txheej txheem corrosion. Kev tsis saib xyuas sab hauv cov hlau metallurgy feem ntau ua rau lub foob tsis ua haujlwm.
Xaus
Xaiv cov khoom siv valve kom raug tsim lub hauv paus rau kev nyab xeeb hauv cov txheej txheem txheej txheem. Kev xaiv cov khoom raug raug, kev tsim qauv tsim nyog, thiab kev tshawb fawb pom tseeb kom ntseeg tau tias cov valve tuaj yeem ua haujlwm hnyav.
