Kev xaiv cov khoom siv rau koj lub foob yog qhov tseem ceeb vim nws yuav ua lub luag haujlwm hauv kev txiav txim siab qhov zoo, lub neej ntev thiab kev ua haujlwm ntawm daim ntawv thov, thiab txo cov teeb meem yav tom ntej. Ntawm no, peb saib seb qhov chaw ib puag ncig yuav cuam tshuam li cas rau kev xaiv cov khoom siv foob, nrog rau qee cov ntaub ntawv feem ntau thiab cov ntawv thov twg lawv haum rau tshaj plaws.
Tej yam ib puag ncig
Qhov chaw uas lub foob yuav raug rau yog qhov tseem ceeb thaum xaiv tus qauv tsim thiab cov khoom siv. Muaj ntau yam khoom tseem ceeb uas cov ntaub ntawv foob xav tau rau txhua qhov chaw, suav nrog kev tsim kom lub ntsej muag foob ruaj khov, muaj peev xwm coj cua sov, tiv taus tshuaj lom neeg, thiab tiv taus kev hnav zoo.
Hauv qee qhov chaw ib puag ncig, cov khoom no yuav tsum muaj zog dua li lwm yam. Lwm yam khoom siv uas yuav tsum tau coj los xav txog thaum xav txog qhov chaw ib puag ncig suav nrog qhov nyuaj, qhov nruj, kev nthuav dav thermal, kev hnav thiab kev tiv taus tshuaj lom neeg. Kev nco ntsoov cov no yuav pab koj nrhiav tau cov khoom zoo tshaj plaws rau koj lub foob.
Ib puag ncig kuj tseem tuaj yeem txiav txim siab seb tus nqi lossis qhov zoo ntawm lub foob puas tuaj yeem ua qhov tseem ceeb. Rau cov chaw ua haujlwm uas nyuaj thiab hnyav, cov foob yuav kim dua vim tias cov ntaub ntawv yuav tsum muaj zog txaus los tiv taus cov xwm txheej no.
Rau cov chaw zoo li no, kev siv nyiaj rau lub foob zoo yuav them rov qab rau lub sijhawm vim nws yuav pab tiv thaiv kev kaw, kev kho, thiab kev kho dua tshiab lossis hloov lub foob kim uas lub foob tsis zoo yuav ua rau. Txawm li cas los xij, hauv cov ntawv thov twj nrog cov kua huv heev uas muaj cov khoom siv lubricating, lub foob pheej yig dua tuaj yeem yuav tau los ntawm kev siv cov bearings zoo dua.
Cov ntaub ntawv foob feem ntau
Cov pa roj carbon
Cov pa roj carbon uas siv rau hauv cov ntsej muag foob yog kev sib xyaw ntawm cov pa roj carbon amorphous thiab graphite, nrog rau feem pua ntawm txhua qhov txiav txim siab cov khoom siv lub cev ntawm qib kawg ntawm cov pa roj carbon. Nws yog ib qho khoom siv inert, ruaj khov uas tuaj yeem ua rau nws tus kheej lubricating.
Nws yog siv dav ua ib qho ntawm ob lub ntsej muag kawg hauv cov khoom siv kho tshuab, thiab nws kuj yog cov khoom siv nrov rau cov khoom sib cais circumferential thiab piston rings nyob rau hauv qhuav lossis me me ntawm lubrication. Cov pa roj carbon / graphite sib xyaw no kuj tuaj yeem impregnated nrog lwm cov ntaub ntawv los muab nws cov yam ntxwv sib txawv xws li txo qis porosity, txhim kho kev ua tau zoo lossis txhim kho lub zog.
Cov roj hmab thermoset resin impregnated carbon seal yog qhov feem ntau siv rau cov roj hmab mechanical seals, nrog rau feem ntau cov roj hmab resin impregnated carbons muaj peev xwm ua haujlwm hauv ntau yam tshuaj lom neeg los ntawm cov hauv paus muaj zog mus rau cov kua qaub muaj zog. Lawv kuj muaj cov khoom sib txhuam zoo thiab cov modulus txaus los pab tswj kev hloov pauv siab. Cov khoom siv no haum rau kev ua haujlwm dav dav txog 260 ° C (500 ° F) hauv dej, cov dej txias, roj, roj, cov tshuaj lom neeg sib xyaw, thiab cov ntawv thov zaub mov thiab tshuaj.
Cov foob pob zeb antimony impregnated carbon kuj tau ua pov thawj tias ua tiav vim yog lub zog thiab modulus ntawm antimony, ua rau nws zoo rau kev siv siab thaum xav tau cov khoom siv muaj zog thiab ruaj khov. Cov foob pob zeb no kuj tiv taus kev tawg hauv cov ntawv thov nrog cov kua dej viscosity siab lossis cov hydrocarbons sib dua, ua rau nws yog qib txheem rau ntau daim ntawv thov refinery.
Cov pa roj carbon kuj tseem tuaj yeem raug impregnated nrog cov yeeb yaj kiab formers xws li fluorides rau kev khiav qhuav, cryogenics thiab cov ntawv thov nqus tsev, lossis oxidation inhibitors zoo li phosphates rau qhov kub siab, ceev ceev, thiab turbine daim ntawv thov rau 800ft / sec thiab ib puag ncig 537 ° C (1,000 ° F).
Cov khoom siv av nplaum
Cov khoom siv ua los ntawm av nplaum yog cov khoom siv tsis muaj hlau uas ua los ntawm cov khoom siv ntuj lossis cov khoom sib xyaw, feem ntau yog alumina oxide lossis alumina. Nws muaj qhov kub yaj siab, qhov nyuaj siab, tiv taus kev hnav thiab tiv taus oxidation, yog li nws siv dav hauv kev lag luam xws li tshuab, tshuaj lom neeg, roj av, tshuaj thiab tsheb.
Nws kuj muaj cov khoom dielectric zoo heev thiab feem ntau siv rau cov hluav taws xob insulators, hnav cov khoom tiv taus, sib tsoo xov xwm, thiab cov khoom kub siab. Hauv cov purities siab, alumina muaj cov tshuaj tiv thaiv zoo rau feem ntau cov kua dej ua haujlwm tsis yog qee cov kua qaub muaj zog, ua rau nws siv rau hauv ntau daim ntawv thov foob tshuab. Txawm li cas los xij, alumina tuaj yeem tawg yooj yim hauv qab thermal shock, uas tau txwv nws siv hauv qee daim ntawv thov qhov twg qhov no tuaj yeem yog qhov teeb meem.
Silicon carbide yog ua los ntawm kev sib xyaw silica thiab coke. Nws zoo ib yam li ceramic, tab sis nws muaj cov yam ntxwv zoo dua thiab tawv dua, ua rau nws yog ib qho kev daws teeb meem zoo rau cov chaw nyuaj.
Nws kuj tseem tuaj yeem rov ua dua thiab txhuam kom lub foob tuaj yeem kho dua ntau zaus hauv nws lub neej. Feem ntau nws siv ntau dua li kev siv tshuab, xws li hauv cov foob tshuab rau nws txoj kev tiv thaiv xeb zoo, lub zog siab, kev tawv siab, kev hnav zoo, kev sib txhuam me me thiab kev tiv taus kub siab.
Thaum siv rau cov ntsej muag foob pob, silicon carbide ua rau muaj kev ua haujlwm zoo dua, lub neej foob ntev dua, cov nqi kho qis dua, thiab cov nqi khiav qis dua rau cov khoom siv tig xws li turbines, compressors, thiab centrifugal twj. Silicon carbide tuaj yeem muaj cov yam ntxwv sib txawv nyob ntawm seb nws tau tsim li cas. Reaction bonded silicon carbide yog tsim los ntawm kev sib txuas silicon carbide rau ib leeg hauv cov txheej txheem tshuaj tiv thaiv.
Cov txheej txheem no tsis cuam tshuam rau feem ntau ntawm cov khoom siv lub cev thiab thermal ntawm cov khoom siv, txawm li cas los xij nws txwv tsis pub cov tshuaj tiv thaiv ntawm cov khoom siv. Cov tshuaj feem ntau uas yog teeb meem yog caustics (thiab lwm yam tshuaj pH siab) thiab cov kua qaub muaj zog, yog li ntawd cov tshuaj silicon carbide uas muaj reaction-bonded yuav tsum tsis txhob siv nrog cov ntawv thov no.
Cov silicon carbide uas tau sintered tus kheej yog ua los ntawm kev sintering cov silicon carbide particles ncaj qha ua ke siv cov khoom pab sintering uas tsis yog oxide hauv ib puag ncig inert ntawm qhov kub tshaj 2,000 ° C. Vim tsis muaj cov khoom siv theem ob (xws li silicon), cov khoom siv sintered ncaj qha yog cov tshuaj tiv taus rau yuav luag txhua yam kua thiab cov txheej txheem uas yuav pom hauv lub twj tso kua mis centrifugal.
Tungsten carbide yog ib yam khoom siv uas siv tau ntau yam xws li silicon carbide, tab sis nws zoo dua rau kev siv siab vim nws muaj qhov elasticity siab dua uas ua rau nws khoov me ntsis thiab tiv thaiv kev cuam tshuam ntawm lub ntsej muag. Ib yam li silicon carbide, nws tuaj yeem rov ua dua thiab txhuam kom du.
Cov tungsten carbides feem ntau yog tsim los ua cov cemented carbides yog li ntawd tsis muaj kev sim los txuas tungsten carbide rau nws tus kheej. Ib qho hlau thib ob raug ntxiv los khi lossis ua kom cov tungsten carbide ua ke, ua rau cov khoom siv uas muaj cov khoom sib xyaw ua ke ntawm ob qho tib si tungsten carbide thiab cov hlau binder.
Qhov no tau siv los ua kom zoo dua los ntawm kev muab kev tawv thiab lub zog cuam tshuam ntau dua li qhov ua tau nrog tungsten carbide ib leeg. Ib qho ntawm qhov tsis muaj zog ntawm cemented tungsten carbide yog nws qhov ceev siab. Yav dhau los, cobalt-bound tungsten carbide tau siv, txawm li cas los xij nws tau maj mam hloov los ntawm nickel-bound tungsten carbide vim nws tsis muaj ntau yam kev sib raug zoo ntawm cov tshuaj lom neeg uas xav tau rau kev lag luam.
Nickel-bound tungsten carbide yog siv dav rau cov ntsej muag foob uas xav tau lub zog siab thiab cov khoom tawv siab, thiab nws muaj kev sib raug zoo hauv tshuaj feem ntau txwv los ntawm nickel dawb.
GFPTFE
GFPTFE muaj kev tiv thaiv tshuaj lom neeg zoo, thiab cov iav ntxiv txo qhov kev sib txhuam ntawm cov ntsej muag sealing. Nws zoo tagnrho rau cov ntawv thov huv si thiab pheej yig dua li lwm cov ntaub ntawv. Muaj cov kev hloov pauv me me muaj los phim cov foob kom haum rau qhov xav tau thiab ib puag ncig, txhim kho nws cov kev ua tau zoo tag nrho.
Buna
Buna (tseem hu ua roj hmab nitrile) yog ib qho elastomer pheej yig rau O-rings, sealants thiab cov khoom pwm. Nws paub zoo txog nws cov kev ua haujlwm kho tshuab thiab ua tau zoo hauv cov roj, petrochemical thiab tshuaj lom neeg siv. Nws kuj tseem siv dav rau cov roj nyoos, dej, ntau yam cawv, roj silicone thiab cov kua hydraulic vim nws tsis yooj ywm.
Vim tias Buna yog cov roj hmab sib xyaw ua ke, nws ua tau zoo hauv cov ntawv thov uas xav tau cov hlau nplaum thiab cov khoom siv tiv taus kev sib txhuam, thiab cov tshuaj lom neeg keeb kwm yav dhau los no kuj ua rau nws zoo tagnrho rau cov ntawv thov sealant. Ntxiv mus, nws tuaj yeem tiv taus qhov kub qis vim nws tau tsim nrog cov kua qaub tsis zoo thiab alkali tsis zoo.
Buna muaj kev txwv rau cov ntawv thov uas muaj cov yam ntxwv hnyav xws li kub heev, huab cua, tshav ntuj thiab cov ntawv thov tiv thaiv pa, thiab tsis haum rau cov neeg sawv cev ntxuav-hauv-chaw (CIP) uas muaj cov kua qaub thiab peroxides.
EPDM
EPDM yog roj hmab hluavtaws uas feem ntau siv rau hauv tsheb, kev tsim kho thiab kev siv tshuab rau cov foob thiab O-rings, tubing thiab washers. Nws kim dua Buna, tab sis tuaj yeem tiv taus ntau yam thermal, huab cua thiab cov khoom siv kho tshuab vim nws lub zog tensile ntev. Nws yog ntau yam thiab zoo tagnrho rau cov ntawv thov uas muaj dej, chlorine, bleach thiab lwm yam khoom alkaline.
Vim nws cov khoom siv elastic thiab nplaum, thaum ncab, EPDM rov qab mus rau nws cov duab qub tsis hais qhov kub thiab txias li cas los xij. EPDM tsis pom zoo rau cov roj av, cov kua dej, cov hydrocarbon chlorinated lossis cov tshuaj hydrocarbon solvent applications.
Viton
Viton yog ib yam roj hmab uas siv tau ntev, ua tau zoo heev, muaj fluorinated, thiab hydrocarbon feem ntau siv rau hauv O-Rings thiab cov foob. Nws kim dua li lwm cov roj hmab tab sis nws yog qhov kev xaiv zoo tshaj plaws rau qhov kev xav tau kev sib khi uas nyuaj thiab xav tau tshaj plaws.
Tiv taus ozone, oxidation thiab huab cua hnyav, suav nrog cov ntaub ntawv xws li aliphatic thiab aromatic hydrocarbons, halogenated fluids thiab cov ntaub ntawv acid muaj zog, nws yog ib qho ntawm cov fluoroelastomers muaj zog dua.
Kev xaiv cov khoom siv kom raug rau kev kaw yog qhov tseem ceeb rau kev ua tiav ntawm daim ntawv thov. Txawm hais tias ntau cov ntaub ntawv foob zoo sib xws, txhua tus ua haujlwm ntau yam los ua kom tau raws li qhov xav tau tshwj xeeb.
Lub sijhawm tshaj tawm: Lub Xya Hli-12-2023