Thaum cov neeg feem coob hnov 'tshwj xeeb alloy fasteners', lawv xav txog lub zog siab bolts rau lub dav hlau cav lossis lub tsheb sib tw. Qhov ntawd yog ib feem ntawm nws, paub meej, tab sis nws kuj yog qhov uas thawj qhov kev tsis txaus ntseeg loj. Nws tsis yog hais txog qhov kawg tensile lub zog. Nws yog hais txog ib puag ncig nws tsis ua haujlwm. Kuv tau pom ntau qhov haujlwm uas ib pab neeg tau txais cov nickel alloy bolt rau kev tiv thaiv corrosion, tsuas yog muaj nws galling thiab txeeb thaum lub sij hawm installation vim lawv overlooked lub galling nyiam ntawm annealed. tshwj xeeb alloy fasteners nyob rau hauv high-clamp quab yuam siv. Daim ntawv qhia tshwj xeeb tau hais tias nws yog 'corrosion-resistant,' thiab lawv tau nres nyeem ntawv. Kev ua haujlwm tiag tiag pib tom qab koj tau xaiv cov khoom siv hauv paus.
Qhov tshwj xeeb hauv Alloy tsis yog Khawv koob
Wb tham txog dab tsi ua ib qho alloy 'tshwj xeeb' rau fasteners. Nws feem ntau yog qhov sib ntxiv ntawm cov ntsiab lus xws li npib tsib xee, cobalt, molybdenum, lossis chromium hauv feem pua tseem ceeb kom ua tiav cov cuab yeej tshwj xeeb. Xav Inconel 718, Hastelloy C-276, lossis MP35N. Tab sis ntawm no yog cov tswv yim ntes: cov alloys no tsis yooj yim rau tshuab. Lawv cov nqi ua haujlwm hnyav heev. Yog tias koj lub tshuab machining tsis tau tawm los ntawm me ntsis - pub tus nqi qeeb dhau, piv txwv li - koj tsis txiav cov khoom ntxiv lawm, koj tsuas yog hardening nws nto nrog lub cuab yeej ntug, uas ua rau cov cuab yeej hnav sai thiab muaj peev xwm subsurface defects nyob rau hauv lub fastener. Qhov no tsis yog theoretical. Peb kawm qhov no nyuaj heev thaum ntxov nrog ib pawg ntawm Waspaloy studs. Cov xov ntsia zoo meej tom qab machining, tab sis thaum lub sijhawm kuaj xyuas ultrasonic, peb pom micro-cracks pib los ntawm cov hauv paus xov. Qhov ua rau? Cov kev ntxhov siab nyob ntawm qhov kev ua haujlwm hnyav dhau los uas tsis tau tom qab kev ntxhov siab-txo kom zoo. Lub alloy's 'tshwj xeeb' cov khoom ua kom pom qhov teeb meem.
Qhov no yog qhov uas koom tes nrog lub chaw tsim khoom thiab lub khw muag khoom uas muaj ntau xyoo dhau los hauv qhov kev ua si tseem ceeb. Kuv tab tom xav txog tus neeg muag khoom uas peb tau ua haujlwm nrog, Qingdao Qiangsenyuan Technology Co., Ltd. (QSY). Lawv keeb kwm hauv peev casting thiab plhaub molding rau ntau tshaj 30 xyoo, tshwj xeeb tshaj yog nrog cobalt thiab npib tsib xee-raws li alloys, muab lawv lub hauv paus xav txog yuav ua li cas cov ntaub ntawv coj los ntawm cov kua hauv lub xeev mus rau qhov tiav. Nws tsis yog hais txog kev khiav CNC program. Nws yog hais txog kev paub tias qee cov nickel alloy xav tau qhov kub ntawm qhov sib txawv thaum lub sijhawm ua haujlwm lossis nws yuav cuam tshuam. Koj tsis tuaj yeem rub qhov kev paub ntawd los ntawm phau ntawv qhia txog kev siv tshuab. Koj tuaj yeem pom ntau ntxiv ntawm lawv txoj hauv kev ntawm lawv qhov chaw, tsi.com. Nws yog qhov kev nkag siab ntawm cov txheej txheem no uas cais cov khoom siv tau los ntawm ib qho kev ntseeg siab.
Lwm qhov nuance yog kev kho cua sov. Rau ntau cov hlau tsis muaj steel, koj muaj qhov ncaj qha quench thiab npau taws. Nrog nag lossis daus-tawv tawv nickel alloys, lub voj voog kev laus yog txhua yam. Lub sij hawm thiab qhov kub thiab txias yuav tsum tau tswj mus rau feeb kom tau qhov zoo sib npaug ntawm lub zog thiab ductility. Kuv nco qab txog qhov xwm txheej uas tus neeg siv khoom yws txog qhov tawg ntawm lawv cov Inconel 718 bolts. Lawv tau muab lawv mus rau txoj cai AMS spec. Raws li kev tshawb fawb, peb pom tias lawv muaj hnub nyoog ntawm qhov raug qhov kub thiab txias, tab sis qhov cub load yog tuab heev, ua rau cov cua sov tsis sib xws thiab muaj kev sib kis ntawm cov khoom siv hluav taws xob thoob plaws hauv batch. Cov uas ua tsis tau zoo yog los ntawm qhov chaw txias dua hauv qhov cub. Cov 'tshwj xeeb' alloy raug tso tseg los ntawm cov txheej txheem kev lag luam uas tau ua tiav yam tsis muaj kev saib xyuas txaus.
Failure Points Koj Tsis Pom Los
Corrosion yog ib lo lus dav. Nrog tshwj xeeb alloy fasteners, peb feem ntau cuam tshuam nrog pitting, crevice corrosion, lossis stress corrosion cracking (SCC) hauv cov xov xwm tshwj xeeb. Lub fastener tej zaum yuav zoo meej rau ib puag ncig roj qaub (H2S resistant) tab sis yuav muaj kev puas tsuaj loj los ntawm chloride-induced SCC nyob rau hauv ib tug ntug dej hiav txwv cua. Qhov kev xaiv tsis yog tsuas yog corrosive los yog tsis. Nws yog hais txog cov kua tshuaj kua uas nws zaum hauv, nrog rau cov kab mob. Peb ib zaug siv titanium alloy fasteners rau seawater daim ntawv thov, ci ntsa iab rau dav dav corrosion. Tab sis lub kaw lus muaj cov kab mob methanol ua cov hydrate inhibitor. Nyob rau hauv qee qhov kev ntxhov siab, qhov no qhia txog kev pheej hmoo ntawm methanol-induced SCC, hom tsis ua haujlwm tsis nyob ntawm peb lub radar qub. Peb yuav tsum rov qab thiab hloov mus rau qib high-qib duplex stainless hlau.
Tom qab ntawd muaj galvanic corrosion. Pairing ib tug noble tshwj xeeb alloy fastener zoo li cobalt-raws li ib tug nrog ib tug txhuas los yog carbon steel qauv yog thov kom muaj teeb meem. Koj nyob nraum qhov tseem ceeb txi lub hauv paus qauv. Lub fastener yuav pristine thaum nws noj cov khoom nyob ib ncig ntawm nws. Txoj kev daws tsis yog ib txwm sib txawv fastener; Qee zaum nws yog hais txog kev sib cais nrog cov ntxhua khaub ncaws tshwj xeeb lossis cov txheej txheej, tab sis cov txheej txheem lawv tus kheej yuav tsum sib haum thiab tsis qhia txog kev pheej hmoo ntawm hydrogen embrittlement. Nws yog ib txoj saw ntawm kev vam meej.
Installation yog nws tus kheej minefield. Lub zog siab ntawm cov fasteners no feem ntau txhais tau hais tias siab dua torque. Ua kom tiav qhov clamp quab yuam yam tsis tau twisting lub taub hau tawm los yog tshaj qhov taw tes tawm ntawm qhov mating yuav tsum tau precision. Lubrication yog qhov tseem ceeb. Kev siv cov roj nplua nyeem tsis raug tuaj yeem ua rau cov kab mob paug hauv aerospace lossis cov ntawv thov zaub mov. Kev siv tsis muaj peev xwm ua rau lub galling kuv tau hais ua ntej. Peb tus qauv tsim tshwj xeeb, tau lees paub los tiv thaiv kev sib txuas rau cov tsev neeg sib txawv, thiab cov kauj ruam yooj yim no tshem tawm txog 80% ntawm peb cov teeb meem kev teeb tsa.
Thaum Casting ntsib Precision Machining
Qhov no yog qhov kev sib tshuam nthuav. Rau cov txheej txheem fastener geometries-xav tias qhov loj, oddly zoo li tus xauv cov txiv ntoo rau lub tshuab turbine, los yog ib lub fastener nrog cov dej sib xyaw ua ke-kev nqis peev casting tuaj yeem yog qhov pib zoo tshaj plaws rau forging lossis machining los ntawm cov khoom lag luam. Koj tau txais ze-net-puab, uas txo qis tus nqi ntawm cov khoom kim heev uas koj xav tau kom tshuab deb. Ib lub tuam txhab xws li QSY, nrog nws ob lub hom phiaj ntawm lub plhaub / kev nqis peev casting thiab CNC machining, tau teeb tsa rau hom kev tsim khoom lag luam.
Qhov kom zoo dua yog cov khoom grain flow. Ib feem machined txiav los ntawm cov qauv nplej. Kev tsim kho kom zoo, ua raws li qhov kub isostatic nias (HIP) lub voj voog kom tshem tawm cov porosity sab hauv, tuaj yeem muaj ntau hom qauv rau cov duab nyuaj. Tom qab ntawd, cov yam ntxwv tseem ceeb ntawm kev thauj khoom-cov kabmob - cov xov, cov kabmob nto, hauv qab lub taub hau radii - yog qhov tseeb machined hauv tsev. Qhov no tswj tag nrho cov nqi saw. Qhov kev pheej hmoo ntawm kev tau txais ib qho casting los ntawm ib tus neeg muag khoom, xa nws mus rau lub khw muag khoom uas tsis paub txog nws cov qauv dendritic tshwj xeeb thiab lub xeev kev ntxhov siab, yog siab heev. Cracking thaum kawg machining yog ib qho tshwm sim, thiab kim, tshwm sim.
Kuv nco qab ntsuas qhov loj Monel K500 cam khwb cia thiab machined flange ntsia liaj qhov rooj rau marine coupling. Cov qauv thawj zaug los ntawm ib qho kev sib txuas ntawm cov khoom siv sib txuas ua tsis tiav ntawm kev hloov xov. Qhov kev soj ntsuam tsis ua hauj lwm tau taw qhia rau micro-shrinkage porosity los ntawm cov casting uas tsis tau kaw tag nrho los ntawm HIP, uas tom qab ntawd ua raws li kev ntxhov siab thaum lub sij hawm threading. Consolidating cov txheej txheem nrog ib tug muab kev pab cuam uas tswj ob qho tag nrho cov kev ncaj ncees casting thiab qhov kawg machining tsis daws nws. Lawv kho lub rooj vag kaw lus ntawm cov pwm casting thiab ua ntej ua qhov khoob ua ntej lub voj voog HIP kawg, tom qab ntawd tiav cov xov. Qhov txawv yog hmo ntuj thiab nruab hnub.
Tus nqi vs. Kev ntseeg tau: Kev suav tiag
Tsis muaj kev sib tham txog tshwj xeeb alloy fasteners yog ua kom tiav yam tsis hais nqi. Ib qho Inconel bolt tuaj yeem raug nqi 50-100 npaug ntau dua li Qib 8 steel ntsia liaj qhov rooj. Lub instinct yog saib qhov twg koj yuav muaj nuj nqis engineer. Qhov no yog qhov kev paub qw kom ceev faj. Hloov cov qib qis qis lossis lees txais qhov dav dav dav kom txuag tau 15% ntawm qhov tuaj yeem ua rau muaj kev pheej hmoo ntawm kev ua tsis tiav, nws cov nqi suav nrog kev poob qis, kev puas tsuaj, thiab kev lav phib xaub.
Kev suav hloov ntawm tus nqi ib feem mus rau tag nrho cov nqi ntawm cov tswv. Nyob rau hauv subsea roj & roj Christmas tsob ntoo, ib tug fastener tsis ua hauj lwm tsis yog ib qho teeb meem txij nkawm; nws yog ib qho kev puas tsuaj ib puag ncig thiab kev tsim khoom kaw raug nqi ntau lab ib hnub. Ntawm no, qhov kev ntseeg tau tsim kho rau hauv lub fastener los ntawm kev xaiv cov khoom siv zoo, tswj kev tsim khoom, thiab kev sim nruj (xws li ASTM F606 kuaj rau cov khoom siv kho tshuab thiab NACE MR0175 rau sulfide kev ntxhov siab tawg) yog tag nrho cov lus pom zoo. Nws yog txoj cai tuav pov hwm.
Qee lub sij hawm, cov tshuaj tsis yog cov khoom sib txawv tshaj plaws. Peb muaj daim ntawv thov kub siab (ze li 650 ° C) qhov chaw pib tsim hu ua cobalt-based superalloy kim heev. Los ntawm kev rov mus xyuas tus qauv tsim, peb pom tau tias peb tuaj yeem txo qhov kev ntxhov siab ntawm lub fastener los ntawm kev hloov kho lub flange tsim me ntsis. Qhov no tau tso cai rau peb kom txo qis mus rau qhov ntau dua tab sis tseem muaj peev xwm nickel-chromium alloy, txuag nqi tseem ceeb yam tsis muaj kev cuam tshuam rau 20 xyoo tsim lub neej. Qhov tseem ceeb yog koom nrog cov fastener thiab cov ntaub ntawv kev txawj ntse thaum ntxov nyob rau hauv lub tsim theem, tsis raws li ib tug procurement afterthought.
Lub Takeaway: Nws yog ib qho system, tsis yog cov khoom
Yog li, dab tsi yog lub ntsiab lus ntawm tag nrho cov no? A tshwj xeeb alloy fastener tsis yog ib yam khoom uas koj rub los ntawm ib phau ntawv. Nws yog ib tug heev engineered system tivthaiv. Nws qhov kev ua tau zoo yog kev ua haujlwm ntawm metallurgy, cov txheej txheem tsim khoom (txawm tias nws yog los ntawm cov khoom siv sib xyaw xws li QSY lossis pab pawg sib koom ua ke), cov txheej txheem kev teeb tsa, thiab kev ua haujlwm tshwj xeeb. Tsis quav ntsej ib qho ntawm cov kev txuas no yog kev caw kom ua tsis tiav.
Kev lag luam tab tom txav mus rau ntau qhov traceability thiab cov ntaub ntawv. Nws tsis txaus kom muaj daim ntawv pov thawj khoom siv lawm. Cov neeg siv khoom xav tau tag nrho batch traceability, machining txheej txheem cov ntaub ntawv, thiab kub kho kab kos. Qhov kev tswj hwm qib no tau dhau los ua tus qauv rau cov ntawv thov tseem ceeb. Nws thawb koj mus rau cov neeg muag khoom uas muaj cov kab ke thiab kev qhuab qhia los muab nws, tsis yog cov cuab yeej siv tshuab xwb.
Thaum kawg, ua hauj lwm nrog cov ntaub ntawv no qhia koj hwm. Lawv tsis yog mos txwv nyiaj. Lawv yog cov cuab yeej uas, thaum nkag siab thiab siv nrog kev paub tob txog lawv qhov kev xav tau thiab cov kev xav tau, ua kom cov thev naus laus zis ua haujlwm hauv qhov chaw nws tsis tuaj yeem ua tsis tau - sab hauv lub dav hlau turbine, hauv qab dej hiav txwv, lossis hauv cov tshuaj corrosive. Qhov ntawd yog tus nqi tiag. Lub fastener nws tus kheej tsuas yog lub cev tshwm sim ntawm tag nrho cov kev paub tshwj xeeb thiab cov txheej txheem tswj.
