Hauv cov choj, cov tshuab hnyav, cua turbine yees, thiab cov tsev hlau loj loj, feem ntau pom cov bolts uas yog xim dub tag nrho -cov no feem ntau tsis yog rau kev tsim kom zoo nkauj, tab sis yog ib qho txiaj ntsig ntawm qhov siab - lub zog bolts ua tiav los ntawm cov txheej txheem kev kho deg tshwj xeeb. Cov xim "dub" no tau dhau los ua tus cim kev nyab xeeb hauv kev ua haujlwm engineering, ua rau muaj kev xav tob ntawm cov khoom siv, cov kev xav tau ntawm corrosion, thiab kev pabcuam kev ntseeg.
Cov xim dub yog los ntawm kev kho blackening, tsis yog kev xaiv zoo nkauj
Feem ntau cov xim dub ntawm flanged screws nrog hexagonal taub hau feem ntau yog vim lawv siv dav siv blackening kev kho mob (tseem hu ua oxidation lossis bluing). Cov txheej txheem no siv cov txheej txheem tshuaj hloov pauv txheej txheej txheej txheem, muab cov ntsia liaj qhov rooj rau hauv cov tshuaj alkaline oxidizing (feem ntau muaj sodium hydroxide thiab sodium nitrite) ntawm 135℃txog 145 degree, ua rau cov txheej tuab ntawm cov hlau nplaum (Fe₃O₄) tsim rau ntawm nws qhov chaw. Cov yeeb yaj kiab no, tsuas yog 0.5-1.5 micrometers tuab, muaj xim sib sib zog nqus xiav mus rau cov xim dub, thiab txawm tias nws thinness, nws muaj ntau yam haujlwm.
Firstly, nws ho txhim khu corrosion kuj. Txawm hais tias blackening zaj duab xis nws tus kheej tsis muaj peev xwm tiv thaiv electrochemical, nws cov qauv ntom ntom zoo cais cov pa oxygen thiab ya raws ntawm huab cua, ncua kev oxidation thiab corrosion ntawm lub hauv paus hlau. Piv nrog rau cov hlau tsis muaj kev kho mob, cov ntsia hlau dub tuaj yeem txuas ntxiv lawv lub neej kev pab ntau zaus nyob rau hauv tsev lossis ib puag ncig corrosive me me, thiab raug nqi - zoo, ua rau lawv tsim nyog rau ntau lawm.
Secondly, nws muab kev sib txhuam zoo heev txo thiab sib dhos lubrication. Cov txheej dub muaj cov qauv microporous uas yooj yim nqus cov roj lubricating lossis xeb -cov roj tiv thaiv, tsim cov txheej txheem lubricating ib ntus thaum lub sijhawm nruj. Qhov no txo cov coefficient ntawm kev sib txhuam ntawm cov xov, ua kom yooj yim dua preload tswj. Qhov no yog tshwj xeeb tshaj yog ib qho tseem ceeb rau kev sib txuas tseem ceeb xws li flanged hexagon taub hau bolts, uas yuav tsum tau nruj torque tswj.
Tsis tas li ntawd, cov xim dub tiav muaj qhov cuam tshuam tsawg hauv cov ntawv thov sab nraum zoov, txo qhov ci ntsa iab thiab txhim kho qhov pom kev nplij siab. Txawm li cas los xij, qhov no yog qhov txiaj ntsig thib ob thiab tsis yog qhov laj thawj tseem ceeb rau kev xaiv cov txheej txheem no.
Hydrogen Embrittlement Risk: Lub Ntsiab Tseem Ceeb Vim Li Cas Electroplating raug txwv rau siab -Lub zog Bolts
Yog li ntawd yog vim li cas ho tsis siv brighter los yog ntau dua corrosion-resistant xim coatings? Qhov teeb meem tseem ceeb nyob hauv hydrogen embrittlement rhiab heev. Fastening screws nrog flanges thiab hex hau (feem ntau yog xa mus rau qib 8.8 thiab siab dua, tshwj xeeb tshaj yog 10.9 thiab 12.9 cov khoom) yog ua los ntawm tempered nruab nrab- carbon alloy steel, uas muaj kev ntxhov siab ntau. Thaum cov txheej txheem ntub dej electroplating xws li zinc thiab cadmium plating, cov tshuaj tiv thaiv cathodic tso tawm hydrogen atoms. Ib txhia ntawm cov hydrogen no nkag mus rau hauv cov hlau lattice, accumulating nyob rau hauv kev nyuaj siab concentration cheeb tsam thiab inducing microcracks. Thaum kawg, qhov no tuaj yeem ua rau muaj kev puas tsuaj tam sim ntawd ntawm flanged hexagon- taub hau threaded bolt yam tsis muaj kev ceeb toom-qhov "ntev brittle fracture" no yog qhov txaus ntshai heev thiab tau ua rau muaj kev sib tsoo ntau yam engineering.
Yog li ntawd, cov txheej txheem thoob ntiaj teb (xws li ISO 4014 thiab GB / T 1231) qhia meej meej tias cov txheej txheem electroplating uas yuav qhia txog hydrogen embrittlement yuav tsum raug zam rau threaded fasteners ntawm flanged hexagon taub hau bolts siv nyob rau hauv load-cov kabmob. Cov txheej txheem blackening cuam tshuam tsis muaj qhov ntws tam sim no thiab ua tsis muaj hydrogen, ua rau nws tau lees paub txoj kev kho kom zoo. Yog li ntawd, dub tsis yog tsuas yog ib tug zoo nkauj feature tab sis kuj yog ib tug txheej txheem kev cog lus kom tshem tawm cov kev pheej hmoo ntawm hydrogen embrittlement.
Cov xim dub ntawm bolts yog qhov tseem ceeb ntawm cov khoom ua haujlwm -kev tsim khoom. Nws ua haujlwm rau ob qho tib si los txo qhov kev pheej hmoo ntawm hydrogen embrittlement thiab sib npaug kev sib dhos kev ntseeg siab nrog tus nqi- ua tau zoo. Hauv kev xyaum ua engineering, cov kws tshaj lij yuav tsum tso tseg qhov kev xav tsis zoo ntawm kev txiav txim siab bolts nkaus xwb los ntawm lawv cov tsos thiab tsuas yog tsom mus rau kev sib raug zoo ntawm cov khoom siv, kev kho cua sov hauv lub xeev, thiab cov txheej txheem kho saum npoo. Tsuas yog nyob rau hauv txoj kev no peb tuaj yeem ua kom ntseeg tau tias txhua tus Hex Head Screw nrog Washer Assembly tuaj yeem tiv taus thiab tso siab rau nws lub zog hauv lub sijhawm tseem ceeb.
Yog tias koj xav kom nkag siab tob txog qhov cuam tshuam ntawm qhov siab - lub zog bolt nto kho cov txheej txheem ntawm kev tswj ua ntej, lossis sib tham txog cov kev xaiv tshwj xeeb rauLub taub hau Bolts nrog Washersnyob rau hauv dynamic loads, thov hu rau peb -peb yuav muab koj nrog kev txawj txhais lus thiab kev pab txhawb rau daim ntawv thov.
Tiv tauj peb
