Cov txheej txheem ntau lawm ntawm titanium alloy seamless tube billets feem ntau suav nrog kev tho thiab extrusion thiab oblique dov tho. Txoj kev tho thiab extrusion feem ntau cuam tshuam ncaj qha extruding rhuab titanium ingots mus rau lub khob hollow hauv lub tog raj kheej extrusion los ntawm lubrication. Oblique dov piercing siv yob thiab cov ntawv qhia kev ruaj khov kom nrawm dhau titanium alloy bar billets los ntawm lub mandrel ruaj kom tau seamless raj billets. Txoj kev tho thiab extrusion muaj kev yooj yim dua nyob rau hauv kev tsim cov tube billets, tuaj yeem tsim cov tube billets ntawm ntau yam kev qhia tshwj xeeb, thiab vim qhov loj deformation thaum extrusion, nws tuaj yeem tawg cov nplej kom ua tiav cov txiaj ntsig zoo. Tsis tas li ntawd, txoj kev no muaj peb - kev taw qhia kev ntxhov siab thaum lub sij hawm extrusion, tso cai rau kev tsim cov tube billets los ntawm cov hlau uas tsis zoo plasticity. Txawm li cas los xij, txoj kev tho thiab extrusion muaj kev siv hlau ntau hauv cov raj xa hluav taws xob ntau lawm, ua rau muaj kev cuam tshuam loj ntawm cov pwm siv, thiab cov cuab yeej siv tau yooj yim nrog cov nqi peev. Ntxiv mus, qhov zoo ntawm cov khoom yog qhov nyuaj rau lav. Txoj kev tho thiab extrusion tuaj yeem muab faib ua ntej extrusion thiab rov qab extrusion. Rov qab extrusion feem ntau yog siv rau loj - txoj kab uas hla thiab siab - deformation - cov kav dej. K. Srinivasan et al. txheeb xyuas qhov ua tau ntawm kev siv qhib tuag rau extrude coj mus muag ntshiab titanium raj. Cov txiaj ntsig tau pom tias qhib tuag rov qab extrusion yuav tsum muaj zog tsawg dua rau pem hauv ntej extrusion, thiab qhov zoo ntawm cov titanium raj tsim los ntawm qhib tuag rov qab extrusion yog siab dua, nrog tsawg dua lubricant noj. Txawm li cas los xij, nws tsuas yog tsim nyog rau kev tsim khoom luv luv fittings. Oblique dov piercing muaj tsawg hlau thiab pwm coj thaum lub sij hawm lub raj billet ntau lawm, thiab muaj qis dua cov kev cai rau lubrication tej yam kev mob thaum ua kom cov khoom nto zoo. Cov cuab yeej siv kuj yooj yim dua thiab muaj cov nqi peev qis dua. Tus nqi tsim khoom ntawm txoj kev no yog kwv yees li 50-70% ntawm qhov tho thiab extrusion. Oblique dov thom khwm kuj tseem muaj qhov tsis zoo, xws li kev tsim cov khoom siv hluav taws xob zoo ib yam nrog cov tsis yooj yim thiab tsis muaj deformation, thiab tsis haum rau nyias-walled tube billets.
Rolling yog txheej txheem tseem ceeb rau kev tsim cov titanium alloy seamless raj. Raws li kev sib txawv dov, nws tuaj yeem muab faib ua kub dov thiab txias dov. Kub dov yog txheej txheem ntawm dov tube billets ntawm qhov kub thiab txias, feem ntau yog teem rau hauv qab ntawm recrystallization kub. Txias dov yog txheej txheem ntawm dov tube billets ntawm chav tsev kub. Feem ntau, kub dov ua rau hnav ntau dua ntawm cov tuag thiab cov yob ntawm cov dov zeb thiab muaj kev tswj xyuas tsawg dua qhov tseeb qhov tseeb piv rau cov yob txias. Yog li ntawd, txias dov yog ib qho kev xaiv zoo dua rau kev tsim cov titanium alloy seamless raj. Raws li qhov sib txawv dov mills siv nyob rau hauv txias dov, nws muaj peev xwm muab faib ua ob - yob txias dov thiab peb - yob txias dov. Tus ntoo khaub lig-section ntawm yob zawj ntawm ob- yob zeb yog maj mam hloov, thiab thaum lub sij hawm dov, lub mandrel thiab lub raj billet tig thiab pub tsis tu ncua. Ob - yob txias yob tuaj yeem ua tiav txoj kab uas hla loj txo, muaj kev ua haujlwm siab, tab sis cov cuab yeej siv tau yooj yim, cov yob tsis yooj yim los hloov, thiab qhov ua tiav ntawm qhov kawg thiab qhov tseeb ntawm cov yob yob tsis zoo. Ib qho peb- yob zeb muaj peb yob faib ntawm 120℃nyob ib ncig ntawm lub raj xa dej, thiab tus ntoo khaub lig- ntu ntawm cov yob grooves ntawm peb yob yog txhua yam sib npaug, tsim ib lub voj voog hom. Thaum lub sij hawm dov txheej txheem, lub crank rocker thiab tus pas nrig system tsav lub swb thiab yob ncej los ua reciprocating linear motion. Peb- yob txias yob cov cuab yeej yog qhov yooj yim, hloov cuab yeej yooj yim, thiab deformation yog ib yam. Qhov zoo ntawm cov dov raj yog qhov zoo, tab sis qhov deformation thaum lub sij hawm dov yog me me thiab cov khoom siv tau tsawg.
Rolling txheej txheem tsis muaj feem cuam tshuam rau kev ua tau zoo thiab zoo ntawm cov raj. Cov txheej txheem ntawm cov raj dov muaj xws li deformation tus nqi, dov hla, pub nyiaj, thiab dov ceev. (1) Tus nqi deformation: Tus nqi deformation muaj kev cuam tshuam rau lub zog dov uas yuav tsum tau ua rau dov cov hlab, qhov zoo ntawm cov hlab dov, cov nyhuv deformation kub, thiab microstructure thiab cov khoom ntawm cov hlab tom qab dov. Qi Yunlian et al. tau kawm txog qhov cuam tshuam ntawm kev deformation ntawm lub tshuab thiab cov khoom ntawm Ti-1300 titanium alloy raj thiab pom tias thaum lub caij txias dov deformation nce ntawm 20% mus rau 30%, ob qho tib si tensile zog thiab plasticity tau txhim kho. Lub zog nce los ntawm 1207.5 MPa mus rau 1223.5 MPa, thiab elongation nce los ntawm 12.75% mus rau 13.25%. (2) Pub tus nqi Tus nqi pub tsis tsuas yog cuam tshuam rau kev tsim khoom ntawm cov yob yob tab sis kuj cuam tshuam rau qhov zoo ntawm cov khoom. Yog tias tus nqi pub tsawg dhau, tus nqi ntau lawm yuav tsawg. Yog tias nws loj dhau, cov hlab ntsha tuaj yeem muaj qhov tsis xws luag xws li burrs, ellipticity, thiab cov phab ntsa tuab tsis sib xws, uas cuam tshuam rau qhov zoo ntawm cov hlab. (3) Rolling passes Nyob rau hauv cov txheej txheem dov, feem ntau nws tsis tuaj yeem dov cov raj mus rau qhov xav tau tshwj xeeb hauv ib kis. Ntau qhov kev hla yuav tsum tau kom tau txais cov khoom xav tau. Txawm hais tias nce tus naj npawb ntawm cov dov hla tuaj yeem txo qhov deformation yuav tsum tau nyob rau hauv txhua qhov kev hla thiab ua rau cov hlab nrog ntau cov phab ntsa tuab, ntau dhau yuav ua rau cov nqi ntau lawm, thiab cov khoom tsim tawm thaum lub sij hawm dov tuaj yeem ua rau qhov zoo ntawm cov hlab hauv ntau qhov kev hla.