Point 1: Taw qhia rau cov teeb meem tshwm sim nrog shrinkage thaum lub sij hawm extrusion txheej txheem ntawm extruder:
Nyob rau hauv extrusion zus tau tej cov aluminium profiles, qhov tsis xws luag feem ntau hu ua shrinkage yuav tshwm nyob rau hauv cov khoom semi-tiav tom qab txiav lub taub hau thiab tus Tsov tus tw tom qab alkali etching tshuaj xyuas. Cov khoom siv kho tshuab ntawm aluminium profiles uas muaj cov qauv no tsis ua raws li qhov yuav tsum tau ua, ua rau muaj kev nyab xeeb.
Nyob rau tib lub sijhawm, thaum cov khoom tsim aluminium alloy profiles raug rau saum npoo los yog kev ua tiav, qhov muaj qhov tsis xws luag ua rau cov khoom siv txuas ntxiv mus, uas yuav cuam tshuam rau qhov chaw tom ntej thiab ua tiav. Hauv qhov xwm txheej hnyav, nws yuav ua rau cov cim zais yuav raug muab pov tseg lossis puas tsuaj rau lub cuab yeej tig thiab lwm yam kev phom sij, qhov no yog ib qho teeb meem tshwm sim hauv kev tsim khoom. Ntawm no, tsab xov xwm no luv luv txheeb xyuas cov laj thawj ntawm kev tsim ntawm aluminium profile shrinkage thiab cov txheej txheem los tshem tawm nws.
Point 2: Kev faib tawm ntawm shrinkage nyob rau hauv extruded aluminium profiles los ntawm extruders: hollow shrinkage thiab annular shrinkage:
1) Hollow shrinkage: Lub hollow yog tsim nyob rau hauv nruab nrab ntawm tus Tsov tus tw kawg ntawm extruded profiles thiab tuav. Cov hlaws dai zoo li lub qhov nrog cov npoo ntxhib lossis ib lub qhov nrog cov npoo uas muaj lwm yam impurities. Lub longitudinal kev taw qhia yog ib tug funnel-puab lub khob hliav qab, lub taub hau ntawm funnel funnel ntsib cov kev taw qhia ntawm hlau ntws. Nws tsuas yog tshwm sim nyob rau hauv ib lub qhov dav hlau tuag extrusion, tshwj xeeb tshaj yog nyob rau ntawm tus Tsov tus tw ntawm profiles extruded nrog me me extrusion coefficients, loj khoom diameters, tuab phab ntsa, los yog roj-stained extrusion gaskets.
2) Annular shrinkage: Ob qhov kawg ntawm lub extrusion shunt molded khoom, tshwj xeeb tshaj yog lub taub hau, yog discontinuous rings los yog arcs, thiab crescent duab yog pom tseeb nyob rau hauv ob sab ntawm lub vuam kab. Lub annular shrinkage ntawm txhua qhov khoom yog symmetrical.
Yog vim li cas rau qhov tsim ntawm shrinkage: Cov neeg kho tshuab mob rau qhov tsim ntawm shrinkage yog tias thaum lub sij hawm advection xaus thiab lub extrusion gasket maj mam mus txog qhov tuag, lub extrusion nce thiab generates lub siab dN nyob rau sab saum toj ntawm lub extrusion chim. Lub zog no ua ke nrog kev sib txhuam quab yuam dT lub tog raj kheej, thaum lub zog sib npaug dN lub tog raj kheej ≥ dT ncoo raug rhuav tshem, cov hlau nyob ib ncig ntawm thaj chaw extruded gasket ntws rov qab raws ntug mus rau hauv nruab nrab ntawm qhov khoob, tsim ib qho shrinkage.
Point 3: Dab tsi yog extrusion tej yam kev mob uas ua rau shrinkage nyob rau hauv lub extruder:
1. Extrusion residual khoom tseem tshuav luv luv
2. Lub extrusion gasket yog oily los yog qias neeg
3. Qhov saum npoo ntawm ingot lossis ntaub plaub tsis huv
4. Qhov kev txiav tawm ntev ntawm cov khoom tsis ua raws li cov cai
5. Lub hauv ob sab phlu ntawm lub tog raj kheej extrusion tsis kam
6. Lub extrusion ceev dheev nce.
Point 4: Cov hau kev los tshem tawm cov shrinkage tsim los ntawm txhuas extrusion tshuab thiab ntsuas los txo thiab tiv thaiv kev tsim ntawm shrinkage:
1. Ua raws li cov txheej txheem nruj me ntsis kom txiav thiab nias qhov dhau, pom lub taub hau thiab tus Tsov tus tw, ua kom lub hauv paus ntawm lub tog raj kheej extrusion tsis zoo, txwv tsis pub roj extrusion gaskets, txo qhov kub ntawm aluminium pas nrig ua ntej extrusion, thiab siv tshwj xeeb convex gaskets. Xaiv qhov tsim nyog ntev ntawm cov khoom seem.
2. Qhov chaw ntawm cov cuab yeej extrusion thiab txhuas rods yuav tsum huv si
3. nquag xyuas qhov loj ntawm lub tog raj kheej extrusion thiab hloov cov cuab yeej tsis tsim nyog
4. Smooth extrusion, lub extrusion ceev yuav tsum tau qeeb nyob rau hauv lub tom qab theem ntawm extrusion, thiab cov seem thickness yuav tsum tau sab laug kom tsim nyog, los yog txoj kev extrusion ntawm nce cov khoom seem yuav tsum tau siv.
Point 5: Yuav kom tshem tawm qhov tshwm sim ntawm shrinkage zoo thaum lub sij hawm tsim cov txhuas profile extrusion tshuab, lub thickness ntawm lub extruder yuav tsum tau them nyiaj mloog mus rau. Cov hauv qab no yog cov qauv siv rau cov tuab tuab:
Extruder tonnage (T) Extrusion thickness (mm)
800T ≥15mm 800-1000T ≥18mm
1200T ≥20mm 1600T ≥25mm
2500T ≥30mm 4000T ≥45mm
Kho los ntawm May Jiang los ntawm MAT Aluminium
Post lub sij hawm: Aug-14-2024
