Thaum ib tug hais Kev 800, thawj yam uas feem ntau los rau hauv lub siab yog nws cov ntaub ntawv: zoo siab-kub lub zog, dlej corrosion kuj, ib tug khoom nickel-hlau-chromium alloy. Tab sis nyob rau hauv lub foundry thiab machining khw, qhov ntawd yog qhov pib taw tes xwb. Cov dab neeg tiag tiag yog nyob rau hauv qhov sib txawv ntawm cov spec thiab lub suab chipping, lub tshav kub tint, thiab qee zaus, ntxhov siab tawg. Kuv tau pom ntau tus qauv kho nws zoo li kev hloov pauv rau 304H lossis 825, thiab qhov ntawd yog qhov pib mob taub hau.
Lub Casting Conundrum: Fluidity vs. Integrity
Casting Kev 800, tshwj xeeb tshaj yog ntawm txoj kev peev casting, yog qhov chaw koj cais txoj kev xav los ntawm kev xyaum. Cov alloy muaj qhov nqaim qis qis, uas yog qhov zoo rau kev txo qis porosity, tab sis nws cov viscosity thaum molten tuaj yeem ua kom yuam kev. Koj tsis tau txais qhov yooj yim ntws ntawm qee cov pa roj carbon steel. Nyob rau hauv peb lub plhaub pwm txheej txheem ntawm Qingdao Qiangsenyuan Technology Co., Ltd. (QSY), peb tau kawm los kho preheat kub ntawm cov pwm ntau aggressively. Ncuav ntawm cov phau ntawv qhia hais tias feem ntau ua rau txias kaw hauv cov seem ntawm cov khoom nyuaj, xws li cov thermowell fittings intricate lossis burner nozzles peb niaj hnub tsim.
Gating system tsim los ua qhov tseem ceeb. Nws tsis yog hais txog kev xa cov hlau xwb; nws yog hais txog kev tswj tus qauv solidification pub rau seem kawg kom solidify. Peb ib zaug muaj ib pawg ntawm cov raj txhawb nqa uas ua rau pom micro-porosity ntawm flange-rau-tube hlws ris. Cov spec tau ntsib, tab sis X-ray qhia ib zaj dab neeg sib txawv. Qhov kho tsis yog qhov hloov pauv loj; nws tau redesigning tus khiav thiab riser layout los tsim ib tug ntau directional solidification rau tus riser. Nws ntxiv qee qhov hnyav rau qhov casting, uas tus neeg siv khoom pib nug, tab sis nws tshem tawm qhov ua tsis tiav. Qhov ntawd yog kev lag luam tawm.
Tom qab ntawd muaj oxide. Cov ntsiab lus chromium thiab aluminium txhais tau hais tias lub ntsej muag oxide ua nrawm nrawm. Yog tias koj lub plhaub pwm tsis zoo tag nrho los yog tsis tshua muaj permeability, koj yuav muaj kev cuam tshuam cov oxide zaj duab xis hauv qhov casting, tsim kom muaj qhov chaw pib zoo tshaj plaws rau kev tawg hauv thermal cycling. Nws yog ib qho tsis xws luag. Koj tuaj yeem xeem dhau qhov ntsuas kub ntawm chav tsev, tab sis nws yuav pom nws lub ntsej muag tom qab ob peb lub hlis hauv kev pabcuam. Peb qhov kev coj ua tam sim no suav nrog kev tswj hwm nruj dua cov dej lwg hauv chav tsev stucco thiab qee zaum txawm tias me ntsis tweak rau deoxidizer xyaum hauv lub ladle, txawm tias koj yuav tsum ceev faj tsis txhob cuam tshuam lwm yam khoom.
Machining: Lub Deceptive Softness
Ntawm daim ntawv, Kev 800 tsis nyuaj heev. Tab sis txhua tus kws kho tshuab uas tau muab lub tshuab txiav tshiab rau nws paub tias nws rov qab sib txawv dua li cov hlau tsis huv. Nws muaj qhov tsis zoo rau kev ua haujlwm-nrhiav, thiab tsis sib xws. Koj tuaj yeem tau txais kev txiav zoo nkauj, tom qab ntawd ntaus qhov chaw uas cov khoom zoo li tau tawv dua, thiab koj cov ntiv tes ntiv tes hnav thaum ntxov. Peb ua ntau yam tom qab-casting CNC machining ntawm QSY, tig valve lub cev, milling flanges. Qhov tseem ceeb peb tau pom yog qhov sib xws: pub noj tsis tu ncua, qhov tob ntawm kev txiav, tsis muaj vaj tse.
Coolant tsis yog ua kom txias ntawm no xwb; nws yog los tiv thaiv no ua hauj lwm-hardening txheej los ntawm kev tsim. Tab sis koj yuav tsum siv hom zoo. Peb txav deb ntawm cov roj ncaj nraim mus rau cov khoom siv hluav taws xob ua haujlwm siab nrog lubricity zoo dua. Lub hom phiaj yog kom tau lub nti tawm sai sai thiab ua kom qhov chaw txiav qhov kub thiab txias tswj. Cia nws kub dhau, thiab cov hlau alloy qhov abrasiveness zoo li ntau, zom los ntawm cov qib carbide txhais tau tias rau super alloys.
Cov cuab yeej geometry tseem ceeb tshaj li cov qauv hlau. Ib tug zoo rake, ib tug ntse ntug, thiab ib tug chipbreaker tsim rau stringy cov ntaub ntawv yog tsis-negotiable. Peb kawm qhov no nyuaj rau thaum ntxov, ua kom zoo nkauj nto tiav uas zais micro-fractures los ntawm cov cuab yeej vibration vim peb tau siv me ntsis tsis zoo rake rau lub zog. Cov khoom tau dhau los ntawm kev tshuaj xyuas tab sis ua tsis tiav hauv kev ntsuam xyuas kev ntxhov siab. Qhov kev soj ntsuam tsis ua hauj lwm taw qhia txoj cai rau kev ua haujlwm ntawm qhov chaw ua haujlwm. Tam sim no, peb qhia meej lub tswv yim toolpath nrog rau cov cuab yeej nws tus kheej rau qhov tseem ceeb Kev 800 cov khoom.
Kev kho cua sov Tightrope
Txhua tus paub tias kev daws annealing yog tus qauv rau Kev 800 kom yaj cov carbide thiab tau qhov ductility rov qab. Qhov zoo tshaj plaws callout yog 1100 ° C yam tsawg kawg nkaus, ceev ceev. Tab sis nrawm yog lo lus ua haujlwm. Hauv ib puag ncig khw, ceev txhais li cas? Dej quench? Rau cov ntu nyias, tej zaum. Tab sis rau tuab-section castings los yog machined blocks, dej quenching qhia nws tus kheej thermal stresses. Peb twb muaj qhov distort, tsis ntau, tab sis txaus los khawb lub ntsej muag precision-machined foob.
Peb tau tsiv mus rau kev quab yuam-cua cua quenching rau feem ntau ntawm peb cov khoom. Nws qeeb qeeb, yog, uas txhais tau tias koj tab tom flirting nrog carbide nag lossis daus yog tias koj tsis ceev faj. Yog li koj yuav tsum tswj lub sij hawm los ntawm qhov cub kom quench, thiab cov airflow yuav tsum yog uniform. Peb tau teeb tsa lub chaw nres tsheb rau cua txias rau peb qhov chaw ua haujlwm kub kub. Nws yog kev nqis peev, tab sis nws txo peb cov khoom seem los ntawm kev kho cua sov distortion ntau dua 70% rau cov ntaub ntawv no. Qee lub sij hawm cov txheej txheem kho muaj txiaj ntsig ntau dua li kev hloov khoom siv.
Lwm qhov nuance yog kev ntxhov siab. Rau qhov chaw uas ua haujlwm hnyav, qhov kev ntxhov siab nruab nrab ntawm qhov ntsuas ntawm 900 ° C tuaj yeem tiv thaiv kev txav mus los thaum lub sijhawm ua tiav. Tab sis koj yuav tsum sau cov kauj ruam no kom meej. Peb ib zaug xa ib batch ntawm manifold castings uas yog tov annealed, ntxhib machined, stress-relieved, ces tag machined. Tus neeg siv khoom tus neeg soj ntsuam tau pom ob lub voj voog kho cua sov thiab tau hais tias nws yog qhov sib txawv. Peb yuav tsum tau muab cov duab micrographs thiab hardness maps thoob plaws ib feem los ua pov thawj qhov kawg microstructure yog lawm thiab tias lub voj voog nruab nrab tsis ua mob rau cov khoom. Nws yog kev sib ntaus sib tua ntawm cov ntaub ntawv tshaj li kev coj ua hauv khw.
Vuam thiab Fabrication Pitfalls
Fabricators nyiam weld Kev 800 rau nws tus kheej los yog carbon steel. Nws yog weldable, paub meej, nrog txoj cai muab tub lim (xws li INCO-Weld 82/182). Tab sis qhov pre-heat thiab interpass kub tswj yog feem ntau glossed tshaj. Qhov no tsis yog hlau me me. Cia nws txias dhau ntawm kev hla dhau, thiab koj muaj kev pheej hmoo tawg hauv HAZ. Peb muab ntau cov cam khwb cia fittings uas tau welded rau hauv cov kav dej. Peb cov ntaub ntawv ntim tam sim no suav nrog cov ntawv pom zoo ntawm cov txheej txheem vuam, tsis yog vim peb yog cov kws tshaj lij vuam, tab sis vim peb tau pom cov kev hu rov qab thaum nws ua tsis ncaj ncees lawm.
Qhov teeb meem loj dua yog qhov sib txawv ntawm vuam. Thaum koj weld Kev 800 rau carbon steel, cov pa roj carbon tsiv teb tsaws los ntawm sab hlau mus rau hauv cov hlau tuaj yeem tsim ib qho chaw nkig. Hauv kev pabcuam kub kub, qhov chaw no tuaj yeem ua tsis tiav. Peb muaj ib rooj plaub uas tus neeg siv khoom welded peb cam khwb cia hlau thermocouple lub tes tsho ncaj qha rau lub nkoj carbon steel. Nws tuav rau ib xyoos, ces tawg ncig txoj cai ntawm tus ntiv taw weld. Lub metallurgy pom pom tseeb carbon diffusion. Cov tshuaj tsis zoo dua vuam; nws tau siv ib qho kev hloov pauv lossis ib qho kev tsim qauv sib txawv. Qee lub sij hawm cov khoom txwv tsis yog nyob rau hauv cov khoom nws tus kheej, tab sis nyob rau hauv yuav ua li cas nws cuam tshuam nrog lub ntiaj teb no.
Kev kho cua sov tom qab vuam (PWHT) yog lwm cov kab mob cab. Koj puas ua nws? Cov lej feem ntau xav tau nws rau cov hlab ntsha siab. Tab sis tag nrho PWHT lub voj voog tuaj yeem dhau hnub nyoog Kev 800 puag hlau yog tias qhov kub thiab txias dhau los yog lub sij hawm ntev dhau, sapping nws creep zog. Nws yog ib qho kev tsis sib haum xeeb ntawm kev tsim khoom thiab cov khoom siv mus sij hawm ntev. Peb lub hom phiaj tam sim no yog kom meej meej nyob rau hauv peb cov ntaub ntawv: Cov khoom no tau raug tshuaj annealed. Ib qho PWHT tom ntej yuav tsum xav txog cov txiaj ntsig ntawm cov khoom siv hlau. Nws thawb lub luag haujlwm engineering rov qab mus rau tus neeg tsim khoom thiab tus tsim qauv, qhov twg nws yuav tsum yog.
Kev tsim khoom thiab Kev Sib Tw Sib Tw
Tsis yog tag nrho Kev 800 yog tsim sib npaug. Cov nominal muaj pes tsawg leeg muaj tolerances, thiab qhov twg ib lub caij poob rau hauv lub band tuaj yeem cuam tshuam kev ua haujlwm. Piv txwv li, aluminium thiab titanium cov ntsiab lus yog qhov tseem ceeb rau kev ruaj ntseg mus ntev ntawm qhov kub thiab txias. Peb muab peb cov khoom lag luam alloy ua tib zoo, thiab rau cov ntawv thov tseem ceeb, peb qhia cov kev ntsuas cua sov kom nyob rau hauv qhov nruj dua, tshwj xeeb tshaj yog rau txhuas. Nws raug nqi ntau dua, tab sis nws yuav twv tau.
Kev ua lag luam yog tag nrho ntawm cov sib npaug sib npaug, feem ntau los ntawm cov mills tshiab. Tej zaum lawv yuav ua tau raws li ASTM B409 spec ntawm daim ntawv, tab sis cov kab ke thiab kev ua kom yaj sib txawv. Peb tau sim ib qho sib npaug rau qhov tsis tseem ceeb ntawm cov khoom cua sov. Nws cam khwb cia zoo, machined zoo. Tab sis nyob rau hauv kev pab cuam nyob ib ncig ntawm 800 ° C, nws pom oxidation scaling ntau tshaj peb li ib txwm cov khoom tom qab tib lub sij hawm. Tus neeg ua txhaum? Tej zaum cov kab mob xws li magnesium lossis calcium cuam tshuam rau oxide adhesion. Nws tsis yog qhov ua tsis tiav, tab sis nws tsis zoo. Peb daig nrog peb tus neeg muag khoom paub txog qhov chaw uas qhov chaw ruaj ntseg tseem ceeb.
Qhov no yog qhov uas tus khub mus sij hawm ntev hauv cov khoom siv sib txuas tseem ceeb. Ib lub tuam txhab zoo li QSY, nrog peb lub xyoo caum hauv casting thiab machining tshwj xeeb alloys, tsis yog tsuas yog yuav hlau; peb tab tom yuav keeb kwm ntawm kev ua tau zoo ib yam los ntawm peb cov mills. Peb tau tsim peb cov txheej txheem tsis nyob ib ncig ntawm tus cwj pwm ntawm cov qib tshwj xeeb. Kev sib pauv mus rau qhov tsis paub sib npaug rov pib dua txhua yam uas tau kawm dhau los rau xoom, qhia txog kev pheej hmoo. Rau peb, kev ntseeg siab ntawm qhov kawg rau cov neeg siv khoom yog tsim nyog rau tus nqi ntawm lub hauv ntej kawg. Nws yog tsawg dua ntawm cov khoom siv nqi ib kilo thiab ntau ntxiv txog tus nqi tag nrho ntawm kev ua tsis tiav hauv daim teb.
Kev xav zaum kawg: Ib qho kev xaiv ua tiav
Yog li, yog Kev 800 cov ntaub ntawv zoo? kiag li. Nws yog ib tug workhorse rau ib tug yog vim li cas - nyob rau hauv lub reformer tubes, tshav kub exchangers, lub cub tawg Cheebtsam. Tab sis nws tsis yog khoom. Nws yog ib qho engineered alloy uas xav tau cov txheej txheem engineered. Nws tus nqi tsis yog nyob rau hauv nws cov muaj pes tsawg leeg, tab sis nyob rau hauv yuav ua li cas txhua kauj ruam ntawm yaj mus rau tag yog tswj nrog ib tug nkag siab ntawm nws quirks.
Qhov kev txawj ntse tiag tiag, hauv kuv qhov kev xav, nyob hauv kev paub thaum twg yuav siv nws thiab yuav ua li cas qhia nws rau txoj haujlwm. Nws tsis yog ib txwm teb. Rau qhov chaw muaj kev kub ntxhov ntau dua, tej zaum koj yuav xav tau 825 lossis 625. Rau lub zog siab kub siab, tej zaum 800H lossis 801. Tab sis rau qhov chaw qab zib ntawm qhov kub thiab txias, carburizing / oxidizing cua, thiab zoo fabricability, nws yog ib qho nyuaj rau tuav. Qhov ua kom yuam kev yog hwm nws tus cwj pwm.
Thaum kawg, kev ua haujlwm nrog cov ntaub ntawv no yog kev sib tham tas li ntawm qhov kev qhia tshwj xeeb, cov txheej txheem, thiab qhov kev pabcuam tiag tiag. Tsis muaj autopilot. Txhua batch, txhua qhov tshiab geometry, yog me ntsis recalibration. Qhov ntawd yog qhov ua rau nws nthuav, thiab hais ncaj ncees, dab tsi ua kom zoo nyob rau hauv qhov chaw uas xaus rau hauv cov nroj tsuag khiav tau ntau xyoo. Koj tsis tuaj yeem xaj xwb Kev 800 tawm ntawm lub vev xaib; koj yuav tsum tsim nws, thiab tsim nrog nws, nrog koj ob lub qhov muag qhib rau cov ntsiab lus.
