Polypropylene (PP) Txhaj Moulding Txheej Txheem Paub meej.

PP feem ntau hu ua polypropylene. Nws tseem hu ua "100% kua nplaum" vim nws qhov kev ua haujlwm zoo. PP yog translucent, semi-crystalline thermoplastic nrog cov yam ntxwv ntawm lub zog siab, zoo rwb thaiv tsev, tsis tshua muaj dej nqus, siab kub distortion kub, tsawg ntom, thiab siab crystallinity. Hloov kho cov khoom siv feem ntau suav nrog cov iav fiber ntau, cov khoom siv ntxhia, cov roj hmab thermoplastic, thiab lwm yam.

Lub fluidity ntawm PP rau kev siv sib txawv yog txawv heev. Tus nqi ntws ntawm PP feem ntau siv yog nruab nrab ntawm ABS thiab PC.

Pure PP yog translucent ivory dawb thiab tuaj yeem dyed rau ntau xim. Rau PP dyeing, tsuas yog xim masterbatch tuaj yeem siv rau ntawm cov tshuab txhaj tshuaj molding. Qee lub tshuab muaj cov yas yas ywj pheej uas txhim khu kev sib xyaw ua ke, thiab tuaj yeem dyed nrog toner. Cov khoom siv sab nraum zoov feem ntau siv UV stabilizers thiab carbon dub filling. Qhov kev faib ua feem ntawm cov khoom siv rov ua dua yuav tsum tsis pub tshaj 15%, txwv tsis pub nws yuav ua rau txo qis zog thiab decomposition thiab discoloration. PP txhaj tshuaj molding feem ntau tsis xav tau kev kho kom qhuav tshwj xeeb ua ntej ua.

Tsis muaj cov cai tshwj xeeb rau kev xaiv cov tshuab txhaj tshuaj molding. Vim tias PP muaj crystallinity siab. Lub tshuab computer txhaj tshuaj molding tshuab nrog kev txhaj tshuaj siab dua thiab kev tswj ntau theem yog xav tau. Lub zog clamping feem ntau txiav txim siab li 3800t / m2, thiab qhov ntim ntim yog 20%-85%.

Cov pwm kub yog {{0}} degree . Rau cov neeg uas xav tau ntau dua, siv cov pwm kub dua. Qhov kub ntawm cov tub ntxhais yog ntau tshaj 5 degree qis dua qhov kub ntawm kab noj hniav, txoj kab uas hla yog 4-7 hli, qhov ntev ntawm rab koob yog 1-1.5 hli, thiab txoj kab uas hla yuav me me li {{7} }.7 hli. Qhov luv ntawm qhov ntev ntawm lub rooj vag ntug, qhov zoo dua, uas yog hais txog 0.7mm. Qhov tob yog ib nrab ntawm phab ntsa thickness thiab qhov dav yog ob zaug ntawm phab ntsa thickness. Nws maj mam nce nrog qhov ntev ntawm cov yaj ntws hauv pwm kab noj hniav. Cov pwm yuav tsum muaj cov khoom cua zoo. Lub qhov cua yuav tsum yog 0.025mm-0.038mm tob thiab 1.5mm tuab. Txhawm rau kom tsis txhob muaj cov cim shrinkage, yuav tsum siv qhov loj thiab puag ncig sprue thiab ncig ntws channel, thiab lub thickness ntawm lub reinforcing tav yuav tsum me me (Piv txwv li, 50-60% ntawm phab ntsa thickness). Lub thickness ntawm cov khoom ua los ntawm homopolymer PP tsis tuaj yeem tshaj 3 hli, txwv tsis pub yuav muaj npuas (cov khoom tuab-walled tsuas yog siv copolymer PP).

Lub melting point ntawm P yog 160-175 degree, thiab decomposition kub yog 350 degree. Txawm li cas los xij, qhov ntsuas kub tsis tuaj yeem tshaj 275 degree thaum lub sijhawm txhaj tshuaj, thiab qhov kub ntawm qhov kub yog qhov zoo dua 240 degree.

Txhawm rau txo qis kev ntxhov siab thiab deformation, kev txhaj tshuaj nrawm yuav tsum raug xaiv, tab sis qee qib ntawm PP thiab pwm tsis haum (cov npuas thiab huab cua tshwm sim). Yog hais tias tus qauv saum npoo tshwm nrog alternating lub teeb thiab tsaus kab txaij kis tau los ntawm lub rooj vag, kev txhaj tshuaj tsawg thiab kub pwm yuav tsum tau siv.

5bar yaj rov qab siab tuaj yeem siv tau, thiab rov qab siab ntawm toner tuaj yeem hloov kho kom tsim nyog.

Siv kev txhaj tshuaj siab dua (1500-1800bar) thiab tuav lub siab (txog 80% ntawm kev txhaj tshuaj siab). Hloov mus tuav lub siab ntawm li 95% ntawm tag nrho cov hlab ntsha tawg thiab siv lub sijhawm tuav ntev dua.

Txhawm rau tiv thaiv shrinkage deformation tshwm sim los ntawm post-crystalization, cov khoom feem ntau yuav tsum tau soaked hauv dej kub.