Molding Process Introduce 注塑工艺介绍

1、pacific ads design training november 2003 1 molding process introduce daniel zuo pacific ads design training november 2003 2 process selection processing of engineering thermoplastics: injection molding extrusion compression molding thermoforming blow molding secondary operations comparisons pacific

2、 ads design training november 2003 3 injection molding extrusion compression molding thermoforming blow molding secondary operations comparisons processing of engineering thermoplastics: materials processingprocessing process selection - injection pacific ads design training november 2003 4 injectio

3、n molding introduction injection molding makes possible mass production of intricate, high performance, tight tolerance parts with very little secondary labor and minimal waste. process selection - injection pacific ads design training november 2003 5 hoppermold clamp extruder barrel with heating ba

4、nds injection molding machine process selection - injection pacific ads design training november 2003 6 injection unit the reciprocating screw pellets feed sectionmelt process selection - injection pacific ads design training november 2003 7 injection unit the reciprocating screw screw pushes forwar

5、d: injectscrew slides back: feed, melt (filling) throat heating coils nozzle rotation injection force back pressure process selection - injection pacific ads design training november 2003 8 injection unit the reciprocating screw screw slides back: feed, melt process selection - injection pacific ads

6、 design training november 2003 9 process selection - injection pacific ads design training november 2003 10 injection unit the reciprocating screw screw pushes forward: inject process selection - injection pacific ads design training november 2003 11 feed section: picks up pellets and carries them f

7、orward. transition section: central portion of the screw with reduced channel depth which compresses plastic, eliminating air between pellets and heating and melting them. metering section: final plasticizing of melt. screw description meteringcompressionfeed process selection - injection pacific ad

8、s design training november 2003 12 clamping system mold movable platen stationary platen provides motion and force to open and close mold clamping force: maximum holding force in tons that a machine can maintain nozzle process selection - injection pacific ads design training november 2003 13 standa

9、rd injection molding fast cycle times complex parts high volume aesthetics advantages disadvantages high pressure process limited large part capability high tooling cost process selection - injection pacific ads design training november 2003 14 co- injection molding pacific ads design training novem

10、ber 2003 15 co- injection molding pacific ads design training november 2003 16 co- injection molding pacific ads design training november 2003 17 lexan foamable resin business machine chassis structural foam part high strength and rigidity in larger parts process selection - injection pacific ads de

11、sign training november 2003 18 mucell微孔发泡设备微孔发泡设备 pacific ads design training november 2003 19 01 needle valve nozzle 02 gas injector 03 mucell-plasticizing screw (l/d ratio: 22:124:1) 04 homogenizing section for gas/melt mixture 05 plastics granules without blowing agent 01 05 030204 mucell微孔发泡工艺的塑

12、化单元微孔发泡工艺的塑化单元 pacific ads design training november 2003 20 mucell微孔发泡的产品表现形式微孔发泡的产品表现形式 pacific ads design training november 2003 21 structural foam injection molding large part capability low pressure process high stiffness to weight ratio advantagesdisadvantages longer cycle time aesthetics blend

13、ing required inert gasblowing agent with resin relative to standard injection molding process selection - injection pacific ads design training november 2003 22 structural foam increases the attainable wall thickness gas expands inside plasticized material to create foam core skin skin core process

14、selection - injection pacific ads design training november 2003 23 gas assist injection molding gas introduced after short shot to pack out part improved aesthetics low pressure process lower part weight reduced cycle time advantagesdisadvantages defect on every part more complex process high toolin

15、g costs licensing costs process selection - injection pacific ads design training november 2003 24 gas assist injection molded shipping container gas assist molded rib injection molded rib gas created cavity gas injection defect sink gas assist injection molding process selection - injection pacific

16、 ads design training november 2003 25 vicat softening point mold temperature process close inject plasticization cool open temperature rise close inject plasticization cool valve unit hot water hot water hot water wait wait cold water cold water heat & cool system process selection - injection pacif

17、ic ads design training november 2003 26 boiler need special equipment process selection - injection pacific ads design training november 2003 27 heat & cool good surface finishing with filled material no weld line increase weld strength eliminate jetting & flow mark paint lessno stress increase flow

18、ability note pc handphone door mirror door handle bezel housing housing lens light guide plate thin wall process selection - injection pacific ads design training november 2003 28 g compressio n go preset gapinjection time positionscrew clamp f= 0 go injection compression molding pacific ads design

19、training november 2003 29 time screw core compressionpreset gap gf= 0gogo injection position selective icm or coining pacific ads design training november 2003 30 featureprocess benefits filling at a larger effective thickness compression assisted filling and pack short shot process lower shear long

20、er fill length lower fill pressure lower clamp force thinner wall capability bi-axial flow reduction of residual stresses material savings weight reduction cycle time reduction better impact properties advantages dimensional stability optical quality weld line strength lower cavity pressure in-mold

21、decorating with “soft touch” why use icm? pacific ads design training november 2003 31 injectionicm nozzle pressure nozzle pressure cavity pressure cavity pressure mold position mold position 25k 15.5k psi psi 2.0 0.004 inch time (sec)time (sec) 0.040 0.3 21k inch 3.7k experimental cavity pressure p

22、rofile pacific ads design training november 2003 32 lexan 141 - 1.5mm thickness icmim improved flow in wheel coversdecrease molded-in stress pacific ads design training november 2003 33 injection molding extrusion compression molding thermoforming blow molding secondary operations comparisons proces

23、sing of engineering thermoplastics: materials processingprocessing process selection - extrusion pacific ads design training november 2003 34 extrusion extrusion is the act of squeezing, pressing, or pushing material through a die in order to make a shape. process selection - extrusion pacific ads d

24、esign training november 2003 35 the extruder pellets part heating coils screw die continuous process process selection - extrusion pacific ads design training november 2003 36 the profile extrusion die continuous flow uniform cross-section process selection - extrusion pacific ads design training no

25、vember 2003 37 extruded through die supported and cooled by a stack of polishing rolls cut and trimmed once below glass transition temperature sheet may be used in thermoforming and compression molding sheet extrusion die extrusion cutaway view rigid sheet roll stack process selection - extrusion pa

26、cific ads design training november 2003 38 die die other roll stack options process selection - extrusion pacific ads design training november 2003 39 thermoplastic and glass composite sheet glass fiber mat glass impregnated sheet sheet extruder a combination of glass mat and thermoplastic resin hav

27、ing both high stiffness and good impact strength. process selection - extrusion pacific ads design training november 2003 40 the extruder pellets part heating coils screwdie low tooling die costs large part capability continuous process advantagesdisadvantages high set-up cost constant cross section

28、 limited complexity process selection - extrusion pacific ads design training november 2003 41 injection molding extrusion compression molding thermoforming blow molding secondary operations comparisons processing of engineering thermoplastics: materials processingprocessing process selection - comp

29、ression pacific ads design training november 2003 42 softened sheet is placed in a mold then pressed into shape by compressive force. process selection - compression compression molding pacific ads design training november 2003 43 2 3 1 soft sheet trimming compressive force part process selection -

30、compression compression molding pacific ads design training november 2003 44 large part capability variable wall thickness uses conventional stamping equipment low warpage and distortion advantagesdisadvantages high tooling cost (cheaper than injection molding) secondary trimming aesthetics process

31、selection - compression compression molding pacific ads design training november 2003 45 injection molding extrusion compression molding thermoforming blow molding secondary operations comparisons processing of engineering thermoplastics: materials processingprocessing process selection - thermoform

32、ing pacific ads design training november 2003 46 vacuum forming atmospheric pressure(14.7 psi) softened sheet mold part vacuum process selection - thermoforming pacific ads design training november 2003 47 pressure forming softened sheet compressed air pressure formed part atm pressure process selec

33、tion - thermoforming pacific ads design training november 2003 48 low tooling cost large part capability low pressure process advantagesdisadvantages low part complexity longer cycle times vacuum process selection - thermoforming thermoforming compressed air pacific ads design training november 2003

34、 49 injection molding extrusion compression molding thermoforming blow molding secondary operations comparisons processing of engineering thermoplastics: materials processingprocessing double walled, hollow parts process selection blow pacific ads design training november 2003 50 pinch bar parison d

35、rop pre blow full pressure release mold part 1 2 3 4 5 process selection blow blow molding pacific ads design training november 2003 51 mandrel parison controlling wall thickness raised mandrellowered mandrel thinner wallthicker wall process selection blow pacific ads design training november 2003 52 double wall geometry (hollow parts) good stiffness to weight ratio low tooling cost large part capability advantagesdisadvantages longer cycle times secondary trimming purging start-up cost process selection blow blow molding pacific ads design training nov