Cov txheej txheem kev siv lub tshuab muaj zog bolts
Cov txheej txheem txheej txheem ntawm lub zog siab bolts yog: kub-dov hlau qws - (txias kos duab) - spheroidizing (softening) annealing - mechanical descaling - pickling - txias drawing - txias forging - xov ua - kho cua sov - tshuaj xyuas
1. Hlau tsim
Hauv kev tsim cov fasteners, kev xaiv kom raug ntawm cov ntaub ntawv fastener yog ib qho tseem ceeb, vim hais tias kev ua tau zoo ntawm fasteners yog ze ze rau lawv cov ntaub ntawv. Yog tias cov khoom siv tsis raug lossis tsis raug xaiv, kev ua haujlwm yuav tsis ua tau raws li qhov yuav tsum tau ua, kev pabcuam lub neej yuav luv, lossis txawm tias muaj xwm txheej lossis kev ua haujlwm nyuaj yuav tshwm sim, thiab cov nqi tsim khoom yuav siab. Yog li ntawd, kev xaiv ntawm cov ntaub ntawv fastener yog qhov txuas tseem ceeb heev. Cold heading steel yog steel rau fasteners nrog high interchangeability uas ua los ntawm txias taub hau txoj kev. Vim nws yog tsim los ntawm cov hlau yas ua nyob rau hauv chav tsev kub, txhua feem muaj ib tug loj npaum li cas ntawm deformation thiab ib tug siab deformation ceev. Yog li ntawd, qhov kev ua tau zoo ntawm cov khoom siv txias txias steel yog nruj heev.
Raws li kev xyaum tsim khoom mus sij hawm ntev thiab kev tshawb fawb neeg siv, ua ke nrog GB/T6478-2001 "Technical Conditions for Cold Heading and Cold Extrusion Steel" GB/T699-1999 "High-Quality Carbon Structural Steel" thiab phiaj JISG3507-1991 "Cold Heading" Cov yam ntxwv ntawm "Carbon Steel Wire Rod for Steel", noj cov khoom siv ntawm qib 8.8 thiab qib 9.8 bolts thiab screws ua piv txwv, kev txiav txim siab ntawm ntau yam tshuaj lom neeg. Yog tias cov ntsiab lus C siab dhau lawm, qhov kev ua haujlwm txias txias yuav raug txo; yog tias nws qis dhau, cov khoom siv kho tshuab ntawm cov khoom tsis tuaj yeem ntsib, yog li nws tau teem rau ntawm 0.25 feem pua -0.55 feem pua . Mn tuaj yeem txhim kho cov permeability ntawm cov hlau, tab sis ntxiv ntau dhau yuav ntxiv dag zog rau cov qauv matrix thiab cuam tshuam rau kev ua haujlwm txias txias; Thaum cov khoom raug quenched thiab tempered, muaj ib tug nyiam txhawb txoj kev loj hlob ntawm austenite nplej, yog li nws yuav tsum tau kho kom tsim nyog raws li thoob ntiaj teb. Nws yog 0.45 feem pua -0.8{17}} feem pua . Si tuaj yeem ntxiv dag zog rau ferrite thiab txo qhov txias formability. SP yog cov khoom tsis huv, thiab nws qhov muaj nyob yuav ua rau muaj kev sib cais raws li thaj tsam ntawm cov nplej, uas ua rau lub embrittlement ntawm grain ciam teb thiab kev puas tsuaj rau cov khoom ntawm cov hlau. Nws yuav tsum tau txo kom ntau li ntau tau. B. Qhov siab tshaj plaws ntawm cov ntsiab lus boron yog 0.005 feem pua, vim hais tias txawm hais tias boron muaj cov nyhuv ntawm kev txhim kho cov permeability ntawm hlau, nws tseem yuav ua rau kom cov hlau brittleness. Cov ntsiab lus boron ntau dhau yog qhov tsis zoo rau cov khoom ua haujlwm xws li bolts, screws, thiab studs uas xav tau cov khoom siv zoo.
2. Spheroidizing (softening) annealing
Thaum lub taub hau countersunk screws thiab hexagon socket lub taub hau bolts yog tsim los ntawm cov txheej txheem txias taub hau, cov qauv qub ntawm cov hlau yuav ncaj qha cuam tshuam rau kev tsim muaj peev xwm ntawm cov txheej txheem txias. Nyob rau hauv cov txheej txheem ntawm lub taub hau txias, cov yas deformation ntawm thaj chaw hauv cheeb tsam tuaj yeem ncav cuag 60 feem pua -80 feem pua, yog li cov hlau yuav tsum muaj cov yas zoo. Thaum cov tshuaj muaj pes tsawg leeg ntawm cov hlau tsis tu ncua, cov qauv metallographic yog qhov tseem ceeb los txiav txim siab cov yas. Nws yog feem ntau ntseeg tias ntxhib flaky pearlite tsis haum rau lub taub hau txias, thaum zoo spherical pearlite tuaj yeem txhim kho qhov muaj peev xwm ntawm cov yas deformation ntawm cov hlau. Rau nruab nrab carbon steel thiab nruab nrab carbon alloy steel nrog ib tug loj npaum li cas ntawm high-strength fasteners, spheroidizing (softening) annealing yog ua ua ntej txias taub hau, thiaj li mus kom tau ib tug uniform thiab nplua spheroidized pearlite kom tau raws li qhov tseeb ntau lawm.
Rau qhov softening annealing ntawm nruab nrab carbon steel hlau rods, lub cua sov kub yuav tsum tau khaws cia saum toj no thiab qis dua qhov tseem ceeb ntawm cov hlau, thiab cov cua kub kub yuav tsum tsis txhob siab dhau heev lawm, txwv tsis pub tertiary cementite yuav precipitate raws li grain ciam teb, ua rau txias. taub hau tawg. Cov hlau pas nrig ntawm nruab nrab carbon alloy steel yog annealed los ntawm isothermal spheroidization. Tom qab cua sov ntawm AC1 ntxiv rau (20-30 feem pua), lub qhov cub txias kom qis dua Ar1, qhov kub yog li ntawm 700 degrees Celsius rau lub sij hawm isothermal, thiab tom qab ntawd lub qhov cub txias txog li 500 degrees Celsius thiab cua- txias. Cov qauv metallographic ntawm cov hlau hloov los ntawm ntxhib mus rau qhov zoo, los ntawm flake mus rau kheej kheej, thiab tus nqi tawg ntawm lub taub hau txias yuav txo qis heev. Qhov dav dav ntawm softening annealing kub rau 35\45\ML35\SWRCH35K steel yog 715-735 degrees Celsius; Thaum qhov dav dav ntawm spheroidizing annealing cua sov rau SCM435\40Cr\SCR435 steel yog 740-770 degrees Celsius, thiab isothermal kub yog 680-700 degrees Celsius.
Peb, tev thiab descaling
Cov txheej txheem ntawm kev tshem cov hlau oxide phaj los ntawm lub taub hau txias steel hlau qws yog stripping thiab descaling. Muaj ob txoj hauv kev: mechanical descaling thiab chemical pickling. Hloov cov txheej txheem chemical pickling ntawm cov hlau rods nrog txhua yam descaling tsis tsuas yog txhim kho cov khoom tsim tau tab sis kuj txo cov pa phem ib puag ncig. Cov txheej txheem descaling no suav nrog txoj kev khoov (lub log puag ncig nrog daim duab peb sab grooves feem ntau yog siv los rov khoov cov hlua hlau), cov tshuaj tsuag cuaj txoj kev, thiab lwm yam., cov nyhuv descaling yog qhov zoo, tab sis cov hlau seem tsis tuaj yeem raug tshem tawm (kev tshem tawm. Tus nqi ntawm cov hlau oxide nplai yog 97 feem pua ) ), tshwj xeeb tshaj yog thaum cov nplai ntawm cov hlau oxide nplai muaj zog heev, yog li ntawd, cov tshuab descaling cuam tshuam los ntawm cov tuab, qauv thiab kev ntxhov siab ntawm cov hlau nplai. Cov pa roj carbon steel hlau rods siv rau lub zog qis (tsawg dua lossis sib npaug li 6.8)
High-strength fasteners (ntau dua los yog sib npaug rau qib 8.8) siv cov hlau rods tom qab txhua yam descaling kom tshem tawm tag nrho cov hlau oxide nplai, thiab tom qab ntawd mus dhau cov txheej txheem tshuaj tua kab mob kom sib xyaw ua ke. Rau qis carbon steel hlau rods, cov ntawv hlau sab laug los ntawm cov neeg kho tshuab descaling yog yuav ua rau tsis sib xws ntawm grain drafting. Thaum cov nplej pob zeb ua raws li cov ntawv hlau thaum cov hlau qws rub tawm ntawm qhov kub thiab txias, qhov saum npoo ntawm cov hlau qws ua rau cov qhab nia ntev. Ntau tshaj 95 feem pua yog tshwm sim los ntawm khawb ntawm qhov chaw ntawm cov hlau hlau thaum lub sij hawm kev kos duab. Yog li ntawd, cov txheej txheem descaling tshuab tsis haum rau kev kub ceev.
4. rub
Cov txheej txheem kev kos duab muaj ob lub hom phiaj, ib qho yog los hloov qhov loj ntawm cov ntaub ntawv raw; lwm qhov yog kom tau txais cov cuab yeej cuab tam ntawm cov fasteners los ntawm deformation thiab ntxiv dag zog. Rau nruab nrab carbon steel, nruab nrab carbon alloy steel kuj muaj lwm lub hom phiaj, uas yog, ua rau cov hlau pas nrig. Lub flaky cementite tau txais tom qab kev tswj kom txias yog tawg kom ntau li ntau tau thaum lub sij hawm kev kos duab los npaj rau cov tom ntej spheroidization (softening) annealing kom tau granular cementite. Txawm li cas los xij, qee cov tuam txhab lag luam arbitrarily txo cov duab kos kom txo tau cov nqi. Kev txo qis ntau dhau ua rau kev ua haujlwm nyuaj ntawm cov hlua hlau, uas cuam tshuam ncaj qha rau kev ua haujlwm txias ntawm cov hlua hlau. Yog tias qhov kev faib tawm ntawm qhov txo qis ntawm txhua qhov dhau los tsis tsim nyog, nws tseem yuav ua rau muaj kev sib tsoo ntawm cov hlua hlau thaum lub sijhawm kos duab.
Tsis tas li ntawd, yog hais tias lub lubrication tsis zoo thaum lub sij hawm kev kos duab, nws kuj tuaj yeem ua rau cov kab nrib pleb tsis tu ncua hauv qhov txias rub hlau pas nrig. Lub tangential kev taw qhia ntawm cov hlau pas nrig thiab cov hlau kos duab tuag yog tsis concentric nyob rau tib lub sij hawm thaum lub hlau pas nrig yog dov tawm ntawm lub tuag, uas yuav ua rau lub hnav ntawm lub unilateral qhov qauv ntawm cov hlau drawing tuag mus rau aggravate, ua rau lub tangential kev taw qhia ntawm cov hlau pas nrig thiab cov hlau kos duab tuag yog tsis concentric nyob rau tib lub sij hawm thaum lub hlau pas nrig yog dov tawm ntawm lub tuag, uas yuav ua rau lub hnav ntawm lub unilateral qhov qauv ntawm cov hlau drawing tuag mus rau aggravate. puab lub qhov tawm ntawm puag ncig, thiab ua rau cov duab tsis sib xws deformation nyob rau hauv lub circumferential kev taw qhia ntawm cov hlau. Lub roundness ntawm steel hlau yog tsis kam rau siab, thiab cross-sectional kev nyuaj siab ntawm cov hlau hlau tsis zoo li thaum lub sij hawm txias taub hau txheej txheem, uas cuam tshuam rau lub txias heading pass tus nqi. Thaum lub sij hawm kev kos duab ntawm cov hlau pas nrig, qhov ntau dhau ntawm qhov txo qhov sib piv yuav ua rau lub ntsej muag zoo ntawm cov hlau hlau tsis zoo, thaum qhov qis qis qis qis tsis zoo rau kev sib tsoo ntawm cov pob zeb cementite, thiab nws yog qhov nyuaj kom tau txais ntau npaum li cas. granular cementite li sai tau. , uas yog, tus nqi spheroidization ntawm cementite yog tsawg, uas yog qhov tsis zoo rau kev ua haujlwm txias ntawm cov hlau hlau. Rau lub bar thiab hlau pas nrig uas tsim los ntawm txoj kev kos duab, ib feem ntawm qhov txo tus nqi yog ncaj qha tswj nyob rau hauv thaj tsam ntawm 10 feem pua -15 feem pua.
5. Txias forging
Feem ntau, txoj kev tsim ntawm lub taub hau ntsia liaj qhov rooj txais kev ua cov yas yas txias. Piv nrog rau cov txheej txheem txiav, cov hlau fiber ntau (hlau hlau) txuas ntxiv nrog rau cov duab ntawm cov khoom, thiab tsis muaj kev txiav hauv nruab nrab, yog li txhim kho lub zog ntawm cov khoom, tshwj xeeb tshaj yog cov khoom siv kho tshuab. Cov txheej txheem txias lub taub hau muaj xws li txiav thiab tsim, ib txoj hauj lwm ib-nias, ob-nias txias taub hau, thiab tsis siv neeg txias taub hau ntawm ntau txoj haujlwm.
Lub tshuab cua txias tsis siv neeg ua haujlwm ntau yam txheej txheem xws li stamping, heading forging, extrusion, thiab txoj kab uas hla txo nyob rau hauv ntau txoj kev tuag. Cov yam ntxwv ua haujlwm ntawm cov khoom qub uas siv los ntawm ib qho chaw nres tsheb lossis ntau qhov kev ua haujlwm tsis siv neeg lub taub hau txias txias yog txiav txim siab los ntawm qhov loj ntawm cov khoom siv loj ntawm qhov bar nrog qhov ntev ntawm 5-6 meters lossis qhov loj ntawm cov hlua hlau. nrog rau qhov hnyav ntawm 1900-2000KG, uas yog, cov yam ntxwv ntawm kev siv tshuab. Lub ntsiab lus yog tias lub taub hau txias tsis siv ua ntej txiav ib qho blanks, tab sis siv lub tshuab txias txias tsis siv neeg nws tus kheej txiav thiab chim siab (yog tias tsim nyog) blanks los ntawm tuav thiab hlau rods. Ua ntej extruding lub kab noj hniav, qhov khoob yuav tsum tau zoo li tus. Ib qho khoob uas ua tau raws li cov kev xav tau tuaj yeem tau txais los ntawm shaping. Ua ntej kev ntxhov siab, txo qis, thiab zoo extrusion, qhov khoob tsis tas yuav ua kom zoo li qub. Tom qab qhov khoob raug txiav, nws raug xa mus rau qhov chaw nres tsheb chim siab thiab shaping. Qhov chaw nres tsheb no tuaj yeem txhim kho qhov zoo ntawm qhov khoob, txo qhov tsim ntawm qhov chaw nres tsheb tom ntej los ntawm 15-17 feem pua, thiab ua kom lub neej ntev ntawm cov pwm, thiab cov bolts tuaj yeem ua nrog ntau txoj kab uas hla.
1. Txoj kev yooj yim tshaj plaws los txiav qhov khoob nrog lub tshuab txiav ib nrab yog siv lub tes tsho txiav; lub kaum sab xis ntawm qhov kev txiav yuav tsum tsis txhob siab tshaj 3 degrees; thiab thaum siv cov cuab yeej qhib, lub kaum sab xis ntawm qhov txiav tuaj yeem ncav cuag 5 -7 degrees.
2. Lub luv luv-loj yuav tsum tau tig 180 degrees thaum lub sij hawm hloov los ntawm lub yav dhau los chaw nres tsheb mus rau lub tom ntej no txoj kev chaw nres tsheb thiaj li hais tias lub peev xwm ntawm lub tsis siv neeg txias heading tshuab yuav exerted, lub fasteners nrog complex lug ua tiav, thiab qhov precision ntawm qhov chaw tuaj yeem txhim kho.
3. Txhua qhov chaw tsim khoom yuav tsum tau nruab nrog lub tshuab punch rov qab, thiab cov tuag yuav tsum tau nruab nrog lub tes tsho-hom ejector ntaus ntawv.
4. Tus naj npawb ntawm cov chaw tsim khoom (tsis suav cov chaw txiav) feem ntau yuav tsum ncav cuag 3-4 chaw nres tsheb (ntau tshaj 5 qhov tshwj xeeb).
5. Thaum lub sijhawm ua haujlwm tau zoo, cov qauv ntawm lub ntsiab slider qhia kev tsheb nqaj hlau thiab cov txheej txheem cov txheej txheem tuaj yeem ua kom ntseeg tau qhov tseeb ntawm qhov punch thiab tuag.
6. Lub davhlau ya nyob twg txwv hloov yuav tsum tau muab tso rau ntawm lub baffle uas tswj cov khoom xaiv, thiab yuav tsum tau them nyiaj mloog mus rau kev tswj ntawm lub zog siab. Qhov tawm-ntawm-roundness ntawm cov xov hlau txias siv hauv kev tsim cov khoom siv lub zog siab ntawm lub tshuab txias tsis siv neeg lub taub hau yuav tsum nyob rau hauv txoj kab uas hla ntawm qhov ntev, thaum lub sij hawm tawm-ntawm-roundness ntawm cov hlau xaim rau ntau cov fasteners yuav tsum. txwv rau 1/1/2. 2 Nyob rau hauv txoj kab uas hla ntawm qhov kam rau ua, yog tias txoj kab uas hla ntawm cov hlau hlau tsis ncav cuag qhov loj me, cov kab nrib pleb yuav tshwm nyob rau hauv qhov kev ntxhov siab lossis lub taub hau ntawm qhov, lossis burrs yuav raug tsim. Yog tias txoj kab uas hla me dua qhov loj me uas yuav tsum tau ua los ntawm cov txheej txheem, lub taub hau yuav ua tsis tiav. , cov npoo thiab cov ces kaum los yog cov tuab tuab tsis meej. Qhov tseeb uas tuaj yeem ua tiav los ntawm cov lus txias txias kuj muaj feem xyuam nrog kev xaiv ntawm txoj kev tsim thiab cov txheej txheem siv.
Tsis tas li ntawd, nws tseem nyob ntawm cov yam ntxwv ntawm cov cuab yeej siv, cov txheej txheem cov yam ntxwv thiab nws lub xeev, qhov tseeb ntawm cov cuab yeej thiab tuag, lub neej, thiab qib ntawm hnav. Rau siab alloy steel siv nyob rau hauv txias taub hau sib sau thiab extrusion, roughness ntawm kev ua hauj lwm nto ntawm cov cemented carbide pwm yuav tsum tsis txhob ntau tshaj Ra=0.2um. Thaum qhov roughness ntawm qhov chaw ua hauj lwm ntawm hom pwm no mus txog Ra=0.025-0.050um, nws muaj lub neej zoo tshaj plaws.
6. Xov xov ua haujlwm
Lub bolt xov feem ntau txias ua hauj lwm kom cov xov dawb paug nyob rau hauv ib tug tej txoj kab uas hla hla los ntawm lub rubbing (dov) hlau phaj (tuag), thiab cov xov yog tsim los ntawm lub siab ntawm hlau phaj (dov tuag). Cov yas streamline ntawm threaded ib feem tsis raug txiav tawm, lub zog yog nce, qhov precision yog siab, thiab qhov zoo sib xws, yog li nws yog dav siv.
Txhawm rau ua kom cov kab sib txuas sab nraud ntawm cov xov ntawm cov khoom kawg, qhov xav tau xov dawb paug txoj kab uas hla yog qhov sib txawv, vim nws raug txwv los ntawm cov khoom xws li xov raug thiab seb cov khoom puas yog coated los yog tsis. Rolling (rubbing) xov yog ib txoj hauv kev uas siv cov yas deformation los ua cov xov hniav. Nws siv lub dov (screwing phaj) tuag nrog tib lub suab thiab cov hniav zoo li cov xov yuav tsum tau ua, thaum extruding lub cylindrical ntsia hlau dawb paug, rotating cov ntsia hlau dawb paug, thiab thaum kawg hloov cov hniav zoo li lub dov tuag rau ntawm lub ntsia hlau. dawb paug, xov yog tsim. Lub ntsiab lus ntawm dov (rubbing) xov ua yog tias tus naj npawb ntawm dov revolutions tsis tas yuav ntau dhau. Yog tias nws ntau dhau, qhov ua tau zoo yuav qis, thiab qhov chaw ntawm cov hniav ntawm cov hniav yuav yooj yim ua rau kev sib cais lossis ib qho buckle random. Ntawm qhov tsis sib xws, yog tias tus naj npawb ntawm cov kiv puag ncig me me dhau lawm, txoj kab uas hla ntawm cov xov yog ib qho yooj yim kom tawm ntawm lub voj voog, thiab lub siab ntawm qhov pib ntawm dov nce qhov txawv txav, ua rau lub neej luv ntawm cov neeg tuag.
Feem ntau cov tsis xws luag ntawm dov threads: tawg los yog khawb ntawm qhov chaw ntawm threaded ib feem; random buckles; tawm ntawm roundness ntawm threaded ib feem. Yog tias cov teeb meem no tshwm sim ntau, lawv yuav raug tshawb pom thaum lub sijhawm ua haujlwm. Yog hais tias tus naj npawb ntawm qhov tshwm sim me me, cov txheej txheem ntau lawm tsis pom cov teeb meem no thiab tom qab ntawd mus rau cov neeg siv, ua rau muaj teeb meem. Yog li ntawd, cov teeb meem tseem ceeb ntawm kev ua haujlwm yuav tsum tau sau tseg, thiab cov ntsiab lus tseem ceeb no yuav tsum tau tswj xyuas hauv cov txheej txheem tsim khoom.
7. Kev kho cua sov
High-strength fasteners yuav tsum tau quenched thiab tempered raws li kev cai. Lub hom phiaj ntawm kev kho cua sov thiab tempering yog txhawm rau txhim kho cov khoom siv kho kom zoo ntawm cov fasteners kom ua tau raws li qhov teev tseg tensile zog tus nqi thiab yield piv ntawm cov khoom. Cov txheej txheem kev kho cua sov muaj qhov cuam tshuam tseem ceeb ntawm cov khoom siv muaj zog, tshwj xeeb tshaj yog lawv qhov zoo. Yog li ntawd, txhawm rau tsim cov khoom siv hluav taws xob zoo tshaj plaws, cov cuab yeej siv hluav taws xob siab thiab cov cuab yeej siv yuav tsum muaj. Vim tias qhov ntim ntau lawm thiab tus nqi qis ntawm lub zog siab bolts, thiab qhov threaded yog cov qauv zoo thiab cov qauv zoo, cov khoom siv kho cua sov yuav tsum muaj peev xwm ntau lawm, qib siab ntawm automation, thiab kev kho cua sov zoo. zoo.
Txij li thaum xyoo 1990, cov kab kev kho cua sov tsis tu ncua nrog kev tiv thaiv huab cua tau ua tiav, thiab cov kev poob siab hauv qab hom thiab mesh siv rauv yog tshwj xeeb tshaj yog haum rau kev kho cua sov thiab tempering ntawm me me thiab nruab nrab-qhov loj me fasteners. Ntxiv rau qhov ua tau zoo sealing ntawm lub cub tawg, lub quenching thiab tempering kab kuj muaj kev tswj hwm lub computer ntawm huab cua, kub thiab txheej txheem tsis ua haujlwm, lub tswb tsis ua haujlwm, thiab tso saib ua haujlwm. High-strength fasteners tau txais kev tswj hwm thiab ua haujlwm los ntawm kev pub mis-tshuaj-tso cua sov-quenching-tu-tempering-xim rau offline, uas ua kom muaj txiaj ntsig zoo ntawm kev kho cua sov. Lub decarburization ntawm cov xov yuav ua rau lub fastener mus ncig ua ntej qhov kev tiv thaiv yuav tsum tau los ntawm cov neeg kho tshuab cov khoom mus txog, uas yuav ua rau tsis ua hauj lwm ntawm threaded fastener thiab shorten lub neej kev pab cuam. Vim yog decarburization ntawm raw khoom, yog hais tias lub annealing yog tsis tsim nyog, decarburized txheej ntawm raw khoom yuav tob. Nyob rau hauv tus txheej txheem ntawm quenching thiab tempering tshav kub kho, ib co oxidizing gas feem ntau yog coj los ntawm sab nraum lub cub tawg. Cov xeb ntawm cov kab hlau los yog cov seem ntawm qhov chaw ntawm cov hlau qws tom qab qhov txias txias yuav decompose tom qab cua sov hauv qhov cub, thiab qee qhov oxidizing gases yuav raug tsim los ntawm cov tshuaj tiv thaiv. Piv txwv li, qhov xeb ntawm cov hlau hlau, uas yog tsim los ntawm hlau carbonate thiab hydroxide, yuav decomposed rau hauv CO2 thiab H2O tom qab cua sov, yog li aggravating decarburization. Cov kev tshawb fawb tau pom tias qib ntawm decarburization ntawm nruab nrab carbon alloy steel yog hnyav dua li ntawm cov hlau, thiab qhov ceev tshaj plaws decarburization kub yog nyob nruab nrab ntawm 700-800 degrees Celsius. Vim hais tias cov ntaub ntawv txuas rau ntawm cov hlau hlau decompose thiab synthesize CO2 thiab H2O sai heev nyob rau hauv tej yam kev mob, yog hais tias lub cub tawg roj ntawm lub nruam mesh siv rauv tsis zoo tswj, lub decarburization ntawm cov ntsia hlau yuav tsis zoo heev. Thaum cov high-strength fasteners yog tsim los ntawm lub taub hau txias, cov ntaub ntawv raw thiab annealed decarburized txheej tsis tsuas yog tseem muaj nyob, tab sis kuj yog extruded mus rau sab saum toj ntawm cov xov. Rau qhov chaw ntawm lub fastener uas yuav tsum tau quenched, qhov yuav tsum tau hardness yuav tsis tau. Mechanical zog (tshwj xeeb tshaj yog lub zog thiab hnav tsis kam) raug txo.
Tsis tas li ntawd, qhov saum npoo ntawm cov hlau hlau yog decarburized, txheej txheej thiab cov qauv sab hauv muaj qhov sib txawv ntawm qhov sib txawv, thiab cov kab nrib pleb tuaj yeem tshwm sim thaum quenching. Vim li no, thaum lub sij hawm quenching thiab cua sov, sab saum toj ntawm cov xov yuav tsum tau tiv thaiv los ntawm decarburization, fasteners uas raw cov ntaub ntawv tau decarburized yuav tsum tau carbonized kom zoo, thiab qhov zoo ntawm kev tiv thaiv huab cua nyob rau hauv lub mesh siv rauv yuav tsum tau kho kom zoo. thawj carbon-coated qhov chaw. Cov ntsiab lus ntawm cov pa roj carbon monoxide yog qhov zoo ib yam kom cov decarburized fasteners tuaj yeem maj mam rov qab los rau cov ntsiab lus carbon qub. Cov pa roj carbon zoo dua yog teem rau ntawm 0.42 feem pua -0.48 feem pua . , yog li kom tsis txhob coarse nplej thiab cuam tshuam rau txhua yam khoom. Cov teeb meem zoo uas yuav tshwm sim nyob rau hauv tus txheej txheem ntawm quenching thiab tempering fasteners feem ntau muaj xws li tsis txaus hardness nyob rau hauv lub xeev quenched; uneven hardness nyob rau hauv lub xeev quenched; ntau dhau quenching deformation; quenching tawg. Cov teeb meem zoo li no feem ntau cuam tshuam nrog cov khoom siv raw, quenching cua sov, thiab quenching txias. Kev tsim kho cov txheej txheem kho cua sov kom raug thiab ua qauv txheej txheem kev ua haujlwm ntau tuaj yeem zam qhov xwm txheej zoo li no.
