Tam sim no, qhov zoo thiab qhov tsis zoo ntawm lub plhaub tseem ceeb ua cov txheej txheem hauv domestic precision casting ntau lawm yog raws li hauv qab no:
1. Tam sim no, muaj peb hom plhaub ua cov txheej txheem dav siv nyob rau hauv domestic precision casting ntau lawm: A. dej iav plhaub; B. Composite plhaub; C. Silica sol plhaub; D sodium silicate plhaub muaj keeb kwm ntau lawm ze li ntawm 50 xyoo nyob rau hauv Suav teb, thiab nws cov nroj tsuag tus naj npawb tseem suav nrog ib qho kev faib ua feem ntau hauv Suav teb' s precision casting manufacturers. Tau ntau xyoo, lub zog ntawm sodium silicate plhaub tau ob npaug, thiab qhov zoo ntawm qhov chaw, qhov tseeb qhov tseeb thiab cov txiaj ntsig ntawm castings tau zoo heev los ntawm kev txhim kho ntawm lub plhaub rov qab refractory thiab nrov thiab siv cov hardener tshiab. Tus nqi qis, lub voj voog luv tshaj plaws, kev ua haujlwm zoo tshaj plaws thiab cov huab cua permeability tseem qis dua rau lwm cov txheej txheem plhaub.
1.1 teeb meem loj
(1) Lub hauv paus tsis zoo ntawm sodium silicate binder yog tias cov ntsiab lus ntawm Na2O yog siab, thiab qhov kub thiab txias zog thiab creep tsis kam ntawm plhaub yog qis dua li ntawm silicon hnyav plhaub. Tsis tas li ntawd, qhov chaw refractory txais yuav quartz xuab zeb (hmoov) nrog tus nqi qis, tsis zoo thiab tsis zoo particle loj grading, yog li nws yuav tsum tsis txhob tau txais high-zoo precision castings.
(2) Plhaub cov xwm txheej tsis zoo thiab tsis muaj cov txheej txheem tsim khoom nruj thiab tswj tsis tau. Vim muaj zog corrosivity ntawm hardener, cov khoom siv tshem tawm plua plav yog yooj yim, thiab ob peb lub rooj cob qhia muaj qhov kub thiab txias, av noo thiab plua plav tshem tawm ib puag ncig. Txheej txheej npaj, hardening, huab cua kom qhuav, dewaxing thiab lwm yam txheej txheem cuam tshuam rau qhov zoo ntawm pwm plhaub thiab casting yog tsis tshua muaj nruj tswj raws li lub lag luam specifications teev los ntawm kev lag luam. Qhov kub, av noo thiab cua ceev ntawm huab cua ziab ib feem ntawm lub plhaub yog tsis tswj, yog li batch scrapping zoo xwm txheej feem ntau tshwm sim nyob rau hauv siab, qis kub los yog plum los nag caij. Nyob rau hauv luv luv, feem ntau factories nyob rau hauv phau ntawv rhiav theem thiab tsim los ntawm technology es tsis yog scientific kev tswj zoo. Qhov no yog ib qho ntawm cov laj thawj tseem ceeb rau qhov tsis ruaj khov casting zoo, cov khoom seem siab thiab kev kho siab ntawm sodium silicate plhaub tau ntau xyoo.
2. Tam sim no, ntau lub chaw tsim khoom siv zircon hmoov, mullite hmoov thiab silica sol plhaub rau thawj thiab thib ob txheej ntawm cov plhaub sib xyaw. Thawj cov txheej txheem dej iav plhaub yuav tsum tseem siv rau cov txheej txheem rov qab. Nws yog ib qho kev txhim kho kev sib txuas ua ke ntawm qhov zoo tshaj plaws ntawm silica sol plhaub thiab qhov zoo ntawm cov nqi qis thiab luv luv ntawm sodium silicate. Piv nrog rau sodium silicate plhaub, qhov zoo ntawm nws cov castings tau zoo heev, lub nto roughness, deg tsis xws luag thiab kho tus nqi tau txo. Lub voj voog ntau lawm zoo ib yam li ntawm sodium silicate plhaub.
2.1 teeb meem loj
(1) Vim hais tias cov iav dej tuav tau khaws cia rau hauv cov txheej txheem rov qab, tag nrho cov kub kub lub zog thiab nkag siab tsis kam ntawm cov pwm pwm yog qis dua li cov silica sol pwm plhaub, thiab qhov tseeb qhov tseeb thiab qhov ntev ntawm cov pwm pwm. yog qis dua cov silica sol pwm plhaub.
(2) Cov huab cua permeability tsis zoo li ntawm sodium silicate plhaub lossis silica sol plhaub. Lub siab kub lub zog ntawm lub plhaub tsis zoo li ntawm silica sol plhaub, uas yog ib qho yooj yim los ua pov tseg.
(3) Qhov kev ruaj ntseg zoo ntawm cov khoom siv plhaub tau zoo dua li ntawm sodium silicate, tab sis nws yog qhov phem dua li ntawm silica sol plhaub.
(4) Vim tias lub plhaub sib xyaw siv cov hmoov zircon kim heev li txheej txheej, lub plhaub nqi yog 4.5 npaug ntawm sodium silicate plhaub. Yog tias cov txheej txheem rov qab siv cov hmoov av mullite, lub plhaub tus nqi yuav luag tib yam li cov silica sol plhaub, thiab nws qhov zoo ntawm cov nqi qis yog tsis pom tseeb.
(5) Qhov nruab nrab kub ciab tsis tuaj yeem siv rau cov plhaub sib xyaw. Qhov nruab nrab kub ciab tsis tuaj yeem dewaxed nrog dej kub. Thaum dewaxing nyob rau hauv autoclave, vim qhov kub thiab txias siab, nruab nrab kub ciab kua yuav muaj ib tug nruj saponification cov tshuaj tiv thaiv nrog dej iav thiab residual hardener nyob rau hauv lub rov qab txheej, yog li nws tsis tuaj yeem rov siv dua yam tsis muaj kev rov qab los.
3. Nyob rau xyoo 1960, raws li lub plhaub plhaub nplaum, silica sol tau siv rau hauv qhov chaw casting. Nrog nws cov txiaj ntsig zoo sib xws, silica sol maj mam hloov cov iav dej dav siv thiab ethyl silicate hydrolyzate nrog txoj kev npaj nyuaj, muaj kuab paug thiab tus nqi siab. Kev xyaum tau ua pov thawj tias siv silica sol tov raws li ceramic plhaub nplaum muaj qhov zoo hauv qab no: txheej txheem kev npaj yooj yim, yooj yim cia txheej, txuas ntxiv siv cov txheej txheej slurry tom qab kho nws cov muaj pes tsawg leeg, txo cov khoom noj, ruaj khov txheej txheej txheej txheem kev ua haujlwm thiab kev ua haujlwm yooj yim, tshem tawm ammonia ziab nrog ethyl silicate hydrolysate, txhim kho qhov chaw ua haujlwm, thiab siv cov cua kub kom qhuav nrog cov av noo tswj tau, Lub plhaub siab lub zog, dej-raws li silica sol, kev nyab xeeb zoo. Nws tau hais tias tom qab hloov los ntawm ethyl silicate mus rau silica sol, lub zog noj yog txo los ntawm 20 ~ 30%, lub plhaub tsim nyog tus nqi yog nce los ntawm 15 ~ 20%, thiab qhov chaw ua hauj lwm zoo heev.
3.1 silica sol (tsawg-kub ciab) pwm plhaub tau yooj yim qhov kub thiab txias ciab tsim, cov cuab yeej yooj yim, me me sib txawv ntawm cov pwm pwm nto roughness, thiab cov txheej txheem yog ruaj khov dua li cov pwm sib xyaw, tshwj xeeb tshaj yog qhov tseeb ntawm qhov casting. Vim tias nws tsis muaj dej iav, lub plhaub pwm muaj qhov ua tau zoo ntawm qhov kub thiab txias, huab cua permeability siab thiab muaj zog creep tsis kam tom qab ci, nws tuaj yeem siv rau ob qho tib si nyias-walled qhov chaw thiab me me thiab nruab nrab qhov chaw nrog cov qauv nyuaj, Nws tuaj yeem siv tau kuj tsim cov khoom loj ntxiv uas hnyav 50 ~ 100kg.
3.1.1 teeb meem uas twb muaj lawm
(1) Vim yog siv cov ciab kub kub, feem ntau ntawm cov pwm plhaub tau dewaxed hauv dej, yog li nws yog ib qho tseem ceeb uas saponification tseem nyob rau hauv lub plhaub pwm, uas yog ib qho yooj yim los tsim inclusions ntawm lub casting, thiab cov kho tus nqi yog me ntsis siab dua.
(2) Lub voj voog ntev ntawm kev ua lub plhaub yog nws qhov loj tshaj qhov tsis zoo thiab tsis muaj peev xwm. Tshwj xeeb tshaj yog nyob rau hauv zus tau tej cov loj qhov chaw nrog sib sib zog nqus grooves, txhua txheej feem ntau qhuav rau 24 ~ 48h.
(3) Tus nqi ntawm silica sol plhaub (tsawg kub ciab) yog 5 npaug siab dua li ntawm sodium silicate plhaub thiab 17% siab dua li ntawm cov khoom sib xyaw. Tus nqi casting yog qhov siab.
3.2 silica sol (qhov nruab nrab kub ciab) plhaub yog siv thoob ntiaj teb precision casting txheej txheem. Nws muaj qhov zoo tshaj plaws casting zoo thiab tus nqi kho qis tshaj. Nws yog tshwj xeeb tshaj yog haum rau me me thiab nruab nrab qhov chaw uas muaj qhov xav tau ntawm qhov chaw roughness siab thiab siab qhov tseeb.
3.2.1 teeb meem uas twb muaj lawm
(1) Tus nqi siab, thiab cov nqi tsim khoom ntawm nws lub plhaub yog 8 npaug ntawm sodium silicate plhaub. Nws tseem yog 25% siab dua li qhov kub thiab txias silica sol plhaub.
(2) Lub voj voog ntau lawm yog tib yam li qhov kub thiab txias silica gel sol plhaub, uas yog ntev npaum li cas ntawm sodium silicate thiab puas plhaub.
(3) Qhov nruab nrab kub ua kua siv quav ciab thiab kev siv tshuaj tua kab mob siab yog feem ntau siv hauv kev tsim cov khoom nruab nrab thiab loj. Cov phab ntsa tuab tuab yog yooj yim rau shrink thiab concave, thiab qhov tseeb qhov tseeb ntawm qhov casting tsis siab dhau. Cov kev xav tau ntawm qhov raug thiab qhov roughness ntawm qhov nruab nrab thiab qhov loj tsis yog siab npaum li cov khoom me me, yog li silica sol (qhov nruab nrab kub ciab) plhaub tsis tshua muaj siv rau qhov nruab nrab thiab loj.
