Txij li yuav luag tag nrho cov kev lag luam fasteners yog ua los ntawm carbon steel thiab alloy steel, dav fasteners yuav tsum tau tiv thaiv corrosion, nyob rau hauv tas li ntawd, kev kho deg ntawm txheej yuav tsum tau ruaj khov, tsis tuaj yeem poob thaum lub installation thiab tshem tawm cov txheej txheem, rau threaded fasteners. , lub txheej yuav tsum nyias txaus kom cov xov tseem yuav spun. Feem ntau, qhov ntsuas kub ntawm cov txheej txheej yog qis dua li ntawm cov khoom siv fastener, yog li nws tseem yuav tsum tau xav txog qhov kev ua haujlwm kub ntawm cov fastener. Rau kev kho saum npoo, tib neeg feem ntau txhawj xeeb txog kev zoo nkauj thiab kev tiv thaiv corrosion, tab sis lub luag haujlwm tseem ceeb ntawm fasteners yog kom nruj qhov chaw, thiab kev kho saum npoo muaj qhov cuam tshuam zoo rau kev ua tau zoo ntawm fasteners, yog li thaum xaiv kev kho deg, cov yam ntxwv ntawm fastening kev ua tau zoo yuav tsum tau txiav txim siab, uas yog, qhov sib xws ntawm installation torque - preload quab yuam. Tus tsim qauv qib siab yuav tsum tsis tsuas yog xav txog kev tsim qauv, tab sis kuj tseem them nyiaj rau kev tsim khoom ntawm kev sib dhos, thiab txawm tias ib puag ncig yuav tsum tau ua. Cov hauv qab no yog ib qho kev qhia luv luv ntawm qee cov txheej txheem feem ntau siv rau fasteners raws li cov ntsiab lus saum toj no rau kev siv los ntawm cov kws kho mob fastener.
1: Galvanizing Galvanizing yog feem ntau siv txheej rau kev lag luam fasteners. Nws yog pheej yig dua thiab zoo dua. Nws tuaj yeem yog xim dub lossis ntsuab ntsuab. Txawm li cas los xij, nws qhov kev tiv thaiv corrosion yog dav dav, thiab nws cov corrosion kuj yog qhov qis tshaj hauv zinc plating (txheej) txheej. General galvanizing neutral ntsev tsuag kuaj hauv 72 teev, kuj tseem muaj cov sealers tshwj xeeb, ua qhov nruab nrab ntsev tsuag tshuaj ntsuam xyuas ntau tshaj 200 teev, tab sis tus nqi yog kim, yog 5 mus rau 8 npaug ntawm cov galvanizing. Electrogalvanizing txheej txheem yog ib qho yooj yim los tsim hydrogen embrittlement, yog li bolts saum 10.9 feem ntau tsis galvanized. Txawm hais tias nws tuaj yeem dehydrogenated los ntawm qhov cub tom qab plating, dehydrogenation yuav tsum tau nqa tawm ua ntej passivation tom qab plating vim hais tias cov passivation zaj duab xis yuav raug rhuav tshem ntawm ntau tshaj 60 degree C. Yog li tsis zoo operability, siab ua nqi. Nyob rau hauv qhov tseeb, cov nroj tsuag ntau lawm yuav tsis nquag dehydrogenate tshwj tsis yog tias tau tso cai los ntawm ib tus neeg siv khoom tshwj xeeb. Electrogalvanized fasteners torque - preload sib xws tsis zoo, thiab tsis ruaj khov, feem ntau tsis siv rau qhov tseem ceeb ntawm kev sib txuas. Txhawm rau txhim kho qhov sib xws ntawm torque-preload, cov txheej txheem ntawm txheej lubricating khoom tom qab plating kuj tuaj yeem siv los txhim kho thiab txhim kho qhov sib xws ntawm torque-preload.
2: Phosphating lub hauv paus ntsiab lus phosphating yog pheej yig galvanized, corrosion kuj yog phem tshaj galvanized. Tom qab phosphating yuav tsum tau coated nrog roj, theem ntawm nws corrosion kuj thiab kev ua tau zoo ntawm cov roj muaj kev sib raug zoo. Piv txwv li, tom qab phosphating, dav siv los tiv thaiv xeb roj, thiab qhov nruab nrab ntsev tsuag tshuaj tsuag tsuas yog 10 mus rau 20 teev. Txheej qib high-qib anti-xeb roj, nws tuaj yeem ncav cuag 72 txog 96 teev. Txawm li cas los xij, nws tus nqi yog 2 mus rau 3 npaug ntawm cov roj phosphating. Ob feem ntau siv fastener phosphating, zinc phosphating thiab manganese phosphating. Lub lubrication kev ua tau zoo ntawm zinc phosphating yog zoo dua li ntawm manganese phosphating, thiab corrosion kuj thiab hnav tsis kam ntawm manganese phosphating yog zoo dua li ntawm galvanizing. Nws tuaj yeem siv tau ntawm qhov kub ntawm 225 txog 400 degrees Fahrenheit (107 txog 204 degrees Celsius). Tshwj xeeb tshaj yog kev sib txuas ntawm qee qhov tseem ceeb. Piv txwv li, txuas pas nrig bolts, ceev, lub tog raj kheej taub hau, lub ntsiab bearings, flywheel bolts, log bolts thiab ceev ntawm lub cav. Lub phosphating ntawm lub zog siab bolts tseem tuaj yeem zam qhov teeb meem ntawm hydrogen embrittling, yog li nyob rau hauv kev lag luam teb, bolts saum toj no 10.9 feem ntau kho nrog phosphating nto.
3: Oxidized (blackened) blackening + oiling yog txheej nrov rau kev lag luam fasteners vim nws yog qhov pheej yig tshaj thiab zoo zoo ua ntej cov roj ntws tawm. Txij li thaum blackening yuav luag tsis muaj peev xwm tiv thaiv xeb, nws yuav xeb sai sai tom qab tsis muaj roj. Txawm tias nyob rau hauv lub xeev cov roj, qhov nruab nrab ntsev tshuaj tsuag tuaj yeem ncav cuag 3 mus rau 5 teev xwb.
4: Cadmium plating cadmium txheej corrosion kuj zoo heev, tshwj xeeb tshaj yog nyob rau hauv Marine huab cua ib puag ncig corrosion kuj zoo dua li lwm yam kev kho deg. Cov nqi kho cov kua khib nyiab hauv kev ua cov cadmium plating yog qhov loj thiab tus nqi siab, thiab nws tus nqi yog li 15 txog 20 npaug ntawm electrogalvanizing. Yog li ntawd, nws tsis yog siv rau hauv kev lag luam dav dav, thiab tsuas yog siv rau qee qhov chaw tshwj xeeb. Piv txwv li, siv nyob rau hauv cov roj drilling platforms thiab hiav txwv aircraft fasteners.
5: electroplating chromium chromium txheej nyob rau hauv cov huab cua yog ruaj khov heev, tsis yooj yim rau discolor thiab poob luster, siab hardness thiab zoo hnav tsis kam. Kev siv cov chromium plating ntawm fasteners feem ntau yog siv los ua cov haujlwm zoo nkauj. Nws yog tsis tshua muaj siv nyob rau hauv kev lag luam teb nrog siab corrosion kuj yuav tsum tau, vim hais tias zoo chrome plated fasteners yog kim li stainless hlau, tab sis thaum lub zog ntawm stainless hlau tsis txaus, chrome plated fasteners yog siv xwb. Txhawm rau tiv thaiv corrosion, tooj liab thiab npib tsib xee yuav tsum tau plated ua ntej chromium plating. Chromium plating tuaj yeem tiv taus kub li 1200 degrees Fahrenheit (650 degrees Celsius). Txawm li cas los xij, nws kuj muaj qhov teeb meem hydrogen embrittlement tib yam li electrogalvanizing.
6: Nickel plating feem ntau yog siv los tiv thaiv corrosion thiab zoo hluav taws xob conductivity. Xws li cov thawj lub davhlau ya nyob twg ntawm lub tsheb roj teeb.
7: Kub dip zinc Kub dip zinc yog zinc rhuab rau cov kua hauv qab thermal diffusion txheej. Nws txheej tuab yog 15 ~ 100μm, thiab nws tsis yooj yim los tswj, tab sis nws muaj kev tiv thaiv corrosion zoo thiab feem ntau yog siv hauv engineering. Kub dip zinc ua yog phem heev, muaj zinc pov tseg thiab zinc chav thiab lwm yam. Vim yog cov txheej tuab, nws ua rau muaj teeb meem uas cov xov sab hauv thiab sab nraud nyuaj rau ntsia hlau rau hauv fasteners. Vim qhov kub ntawm qhov kub dipping zinc ua, (340-500C) nws tsis tuaj yeem siv rau fasteners siab tshaj 10.9 qib.
8: Zincizing zincizing zinc hmoov khoom metallurgical thermal diffusion txheej. Lub uniformity yog qhov zoo, thiab cov khaubncaws sab nraud povtseg tuaj yeem tau txais hauv cov xov thiab qhov muag qhov muag. Cov txheej tuab yog 10 ~ 110μm, thiab qhov yuam kev tuaj yeem tswj tau ntawm 10%. Nws txoj kev khi lub zog thiab kev tiv thaiv corrosion nrog lub substrate yog qhov zoo tshaj plaws hauv zinc txheej (electrogalvanizing, kub dipping zinc, dacromet). Nws cov txheej txheem ua yog tsis muaj kuab paug thiab feem ntau ib puag ncig tus phooj ywg.
9: Dacromet tsis muaj teeb meem hydrogen embrittleness, thiab torque-preload sib xws kev ua tau zoo. Yog tias koj tsis xav txog cov teeb meem ntawm chromium thiab kev tiv thaiv ib puag ncig, nws yog qhov tsim nyog tshaj plaws rau cov khoom siv muaj zog nrog kev tiv thaiv corrosion siab.
