(1) txheej txheem molding
① cov khoom xyaw thiab nws cov txheej txheem. PVC phaj npaj zoo ncaj qha cuam tshuam rau extruder extrusion ceev, txheej txheem tsis thiab khoom zoo, yog li ntawd yuav tsum ncaj qha tswj tus txheej txheem
Cov khoom xyaw hauv cov kua mis thaum lub sijhawm ntawm cov khoom siv los ntsuas, los tiv thaiv kev ntsuas ntawm qhov yuam kev loj vim los ntawm qhov tseeb cov kev hloov pauv, qhov no ua rau qhov zoo ntawm kev ntsuam xyuas thiab kev tswj kom zoo. Qhov taw tes hauv cov txheej txheem ntau lawm yog ib qho yooj yim rau kev saib xyuas, yuav tsum ua kom txaus.
Mixed temperature. Qhov sib tov yog feem ntau yog ua tiav hauv kev siab ceev tov. Cov khoom nyob rau hauv lub tov kub high-speed txhuam tshav kub, nyob rau hauv lub mixing txheej txheem, qhov kub tswj yog tseem ceeb heev. Kub tswj yuav tsum them nyiaj rau ob lub ntsiab lus: Ua ntej, PVC cov khoom thiab cov khoom ntxiv rau cov khoom tov, kev sib tov tam sim ntawd, kev siv kev sib txhuam cua sov, thaum ntsuas qhov kub txog 120T los yog thaum lub zes rau lub cav txias txias; Qhov thib ob, qhov kub sib tov nyob hauv lub tshuab txias txias rau lub sijhawm rau lub sijhawm, thaum cov khoom kub yog qis dua 45 thiaj li yuav qhib qhov txias tov nrog lub rooj vag paug.
B. Ncaim sijhawm. Cov ntaub ntawv nyob rau hauv kev sib xyaw cov txheej txheem tau ntsib kev hloov hauv kev sib nraus, tsis meej thiab ib feem ntawm txheej txheem ntawm gelation, thaum tshem cov khoom siv hauv dej thiab tsis muaj zog, siv sij hawm ua kom tiav. Nws lub sij hawm ntev dhau lawm, yuav ua rau kev nyuaj siab ploj yog qhov nyuaj, cov khoom siv yaj sij hawm ntev ntev, khoom muag zoo dua qub; Nws lub sij hawm ntev dhau lawm, qhov kub thiab txias yuav nce siab, yooj yim ua rau cov khoom siv zis, thiab lub zog noj, cov khoom ua tau tawm tsawg tsawg.
C. Txiav noj. RPVC phaj cheebtsam yog qhov tseemceeb uas yuav tau xaiv qhov kev txiav txim siab pub mis yog qhov tseemceeb heev, kev xaiv kev noj zaubmov yuav tsum ua kom zoo rau lub luag haujlwm ntawm cov khoom ua si kom tsis txhob muaj kev sib tawm tsam ntawm cov txiaj ntsim zoo, tab sis kuj pab txhawm rau txhim kho qhov kev faib tawm.
Raug kub thiab txias sib xyaw cov txheej txheem yog raws li nram no.
(A) lub PVC resin nyob rau hauv high-speed tov kom rub kom txog 60 lub sij hawm.
(B) Muab tus stabilizer thiab ntxiv kom kub txog 90 °.
(C) rau hauv lub roj nplaum, cov khoom siv hluav taws xob, cov khoom hloov txav, cov xim, cov xim rau xim thiab lwm yam.
(D) peev nyiaj sab nraud ntawm lub roj nplua nyeem, ntxiv kom kub li 115 ~ 120T.
(E) cov khoom ntawm qhov qis qis yog tso tawm mus rau hauv cov cua txias kom txias nrog dej txias.
⑴ txias tov rau 40 ~ 45
Lub ntsiab zoo ntawm hmoov yog cov khoom nyob rau hauv kev npaj ntawm cov txheej txheem kub yog luv, cov khoom yuav tsum tau siv tsawg, luv luv voj voog. Nws lub ntsiab drawback yog cov khoom pluag uniformity thiab tsis zoo ntawm kev ua tus txheej txheem, cov nqi nquag yog loj. Hmoov yuav ncaj qha siv rau extrusion (feem ntau yog twin-ntsia hlau extruder extrusion), tab sis kuj los ntawm cov yas granulation rau hauv pellets rau cov tib pliab extruder ntau lawm phaj.
② extrusion molding txheej txheem. Extrusion molding yog ib qho tseem ceeb tshaj plaws ntawm tag nrho cov txheej txheem ntawm cov khoom extruded. Cov moulding kub, extrusion ceev thiab lwm cov txheej txheem tsis ncaj qha mus rau qhov zoo ntawm daim ntawv.
A. Moulding kub. RPVC phaj moulding temperature yog nyob ntawm tus qauv, lub thickness ntawm phaj thiab lwm yam los txiav txim. Lub hau kub ntawm tus ntaiv tib lub vias extruder yog: qhov ncauj. Lub ^ ^ ^ 140, 150 ~ 160t, 170 ~ 180 ^. Qhov ntsuas kub ntawm qhov seem ntawm cov ntxaib twv sib tw yog ib nyuag siab me ntsis kom cov khoom siv yaj tuaj yeem ua kom tiav rau qhov kawg ntawm qhov seem noj kom thiaj li ntim tus pas nrig los tiv thaiv cov khoom siv tawm ntawm lub qhov pa tawm. Lub taub hau txuas kub thiab lub taub hau kub
B. Kev rho tawm ceev. Lub rhiab ceev yog txiav txim siab los ntawm kev sib zog ntawm lub hau ntswj, qhov ceev ceev nce, qhov extrusion ntim nce thiab qhov extrusion ceev yog ceev. Nyob rau hauv tib lub molding kub mob, qhov zoo ntawm cov khoom pov thawj ntawm cov khoom yuav txo thiab qhov tsim nyog rau qhov ceev (viav vias ceev) Los xyuas kom cov khoom zoo thiab txhim kho kev lag luam zoo yog qhov tseem ceeb heev.
C. Tig ceev. Txoj hlua khau tawm ntawm cov tsho me nyuam yuav tsum ceev nrawm dua li ntawm peb qho ntawm lub calender kom muaj ib qho kev nruj kom daim ntawv tsis deform, xws li warping thaum lub caij txias. Tab sis qhov ceev ceev dhau thaum phaj yuav muaj kev ntxhov siab ntau dua, cuam tshuam zoo ntawm kev ua cov khoom ua tiav.
D. Kev xav txias stereotypes. Qhov tseem ceeb ntawm peb-yob calender yog calendering thiab txias. Qhov ntsuas kub ntawm lub raj nyuj yog qhia nyob rau hauv Table 5-2. Qhov deb ntawm peb lub thawv thiab lub di ncauj tuag yuav tsum yog me me li qhov ua tau, feem ntau yog 5 mus rau 10 cm. Yog hais tias loj dhau, lub tshuab tawm ntawm lub rooj tsavxwm yooj yim rau sagging wrinkles, saum npoo roughness, thiab yooj yim rau cua sov, tsis pom zoo. Lub hau ntev yuav tsum yog me ntsis loj dua lub taub hau dav. Ua rau lub yoojyim ntawm lub yob nce lub yob lub sij hawm thiab ua rau extrusion ceev thiaj li hais tias lub gloss ntawm PVC ntawv yog zoo. Qhov ua hauj lwm nrug ntawm nruab nrab thiab nruab nrab rollers ntawm peb-yob calender yuav ua tau me ntsis loj dua lub thickness ntawm lub phaj. Triacent traction ceev thiab extrusion ceev ntawm extruder yuav tsum zoo ib yam, sim kom tsis txhob ncab.