cetak plastik ok

7/21/2019 Cetak Plastik OK

http://slidepdf.com/reader/full/cetak-plastik-ok-56da463b729b7 1/30

Cetak Plastik Cetak Plastik 

Plastics Injection MoldingPlastics Injection Molding

7/21/2019 Cetak Plastik OK

http://slidepdf.com/reader/full/cetak-plastik-ok-56da463b729b7 2/30

Sejarah Plastik

7/21/2019 Cetak Plastik OK

http://slidepdf.com/reader/full/cetak-plastik-ok-56da463b729b7 3/30

Jenis

plastik/polimer

Thermoset Thermoplastic

7/21/2019 Cetak Plastik OK

http://slidepdf.com/reader/full/cetak-plastik-ok-56da463b729b7 4/30

Sifat Umum: tahan lama, keras, tangguh, ringan.

Thermoset

Contoh:

Polyester: lacquers, varnishes, perahu, furniture

Epoxy dan Resin: lem, coating untuk electrical circuits,

composite: fiberglass baling-baling helicopter, perahu

7/21/2019 Cetak Plastik OK

http://slidepdf.com/reader/full/cetak-plastik-ok-56da463b729b7 5/30

Elastomer

Sifat Umum: thermoset, seperti sifat karet

Contoh:

Polyurethan: matras, cushion, insulation, mainan

Silicon: sarung tangan medis, masker, seal

7/21/2019 Cetak Plastik OK

http://slidepdf.com/reader/full/cetak-plastik-ok-56da463b729b7 6/30

• umumnya thermosetting polymer

• mold dipanaskan dan ditutup dengan tekanan

• Plastik mengalir kedalam rongga

• perlu finishing

Peralatan makan, handel ketel, ski,

Casing untuk circuit breaker, sol sepatu,fiber-reinforced composite

7/21/2019 Cetak Plastik OK

http://slidepdf.com/reader/full/cetak-plastik-ok-56da463b729b7 7/30

Sifat Umum: suhu leleh rendah, lunak, flexible

Contoh:

Polyethylene: packaging, electrical insulation, milk and waterbottles, packaging film 

Polypropylene: carpet fibers, automotive bumpers, microwavecontainers, prosthetics

Polyvinyl chloride (PV: electrical cables cover, credit cards, carinstrument panels

Polystyrene: disposable spoons, forks, !tyrofoam"!crylics (P""!: polymethyl methacrylate: paints, fake fur,

plexiglassPolyamide (nylon#: textiles and fabrics, gears, bushing andwashers, bearings

PET (polyethylene terephthalate: bottles for acidic foods like #uices,food trays

PT$E $polytetrafluoroethylene: non-stick coating, %ore-&ex"

$raincoats, dental floss

Thermoplastik

7/21/2019 Cetak Plastik OK

http://slidepdf.com/reader/full/cetak-plastik-ok-56da463b729b7 8/30

7/21/2019 Cetak Plastik OK

http://slidepdf.com/reader/full/cetak-plastik-ok-56da463b729b7 9/30

7/21/2019 Cetak Plastik OK

http://slidepdf.com/reader/full/cetak-plastik-ok-56da463b729b7 10/30

Proses Pen%olahan Plastik

7/21/2019 Cetak Plastik OK

http://slidepdf.com/reader/full/cetak-plastik-ok-56da463b729b7 11/30

Extrusion

pelletsopen cross-sections (channels) closed cross-sections (tubes, pipes) pelletsopen cross-sections (channels) closed cross-sections (tubes, pipes)

7/21/2019 Cetak Plastik OK

http://slidepdf.com/reader/full/cetak-plastik-ok-56da463b729b7 12/30

&lo' moldin%

heated glass

3-piece mold

(a) The hollow piece of heated glass (parison)

is first created by a blow mold

(see text-book Fig 1!"#)

(b) The mold is put together 

(c) $lunger and hot air push the

glass up

(d) %ot air blows the glass out towards

the mold surface

(e) &old comes apart, bottle is remo'ed

heated glass

3-piece mold

(a) The hollow piece of heated glass (parison)

is first created by a blow mold

(see text-book Fig 1!"#)

(b) The mold is put together 

(c) $lunger and hot air push the

glass up

(d) %ot air blows the glass out towards

the mold surface

(e) &old comes apart, bottle is remo'ed

7/21/2019 Cetak Plastik OK

http://slidepdf.com/reader/full/cetak-plastik-ok-56da463b729b7 13/30

Thermoormin% 

Lembaran plastik Pemanasan (lunak) Dicetak sesuai bentuk 

7/21/2019 Cetak Plastik OK

http://slidepdf.com/reader/full/cetak-plastik-ok-56da463b729b7 14/30

Vacuum thermoormin%

7/21/2019 Cetak Plastik OK

http://slidepdf.com/reader/full/cetak-plastik-ok-56da463b729b7 15/30

ompression and Transer "oldin% 

compression molding

transfer molding

$bentuk lebih rumit

7/21/2019 Cetak Plastik OK

http://slidepdf.com/reader/full/cetak-plastik-ok-56da463b729b7 16/30

)njection "oldin% 

- Paling banyak digunakan, penting, dan ekonomis.

7/21/2019 Cetak Plastik OK

http://slidepdf.com/reader/full/cetak-plastik-ok-56da463b729b7 17/30

Skematik ProsesSkematik Proses ** "esin"esin

+

' !ource: http:((www.idsa-mp.org(proc(plastic(in#ection(in#ection)process.htm

+

Skematik mesin )njection moldin% thermoplastik

7/21/2019 Cetak Plastik OK

http://slidepdf.com/reader/full/cetak-plastik-ok-56da463b729b7 18/30

7/21/2019 Cetak Plastik OK

http://slidepdf.com/reader/full/cetak-plastik-ok-56da463b729b7 19/30

Pen%aruh suhuPen%aruh suhu moldmold dandan

tekanan terhadap penyusutantekanan terhadap penyusutan

0.030

0.000

0.010

0.005

0.015

0.020

0.025

100 120 140 160 180 200 220 240

Mold Temperature (F)

LP! PP

"#lo$ 6%6

PMM&

&'etal

      (      )     r      i     $      k     a     *

     e

0.030

0.000

0.010

0.005

0.015

0.020

0.025

      (      )     r      i     $      k     a     *     e

6000

8000

10000

12000

14000

16000

Pressure o$ i$+e'tio$ plu$*er(psi)

&'etal

LP!

"#lo$6%6

PP

,it-o,

18000

PPa'ross

-o,

PMM&

7/21/2019 Cetak Plastik OK

http://slidepdf.com/reader/full/cetak-plastik-ok-56da463b729b7 20/30

)njection "oldin%:

&entuk/%eometri "old 

*omponen utama:

mold pieces $menentukan bentuk(geometri produk,

 sprue, gates, runners, vents, ejection pins,cooling system 

7/21/2019 Cetak Plastik OK

http://slidepdf.com/reader/full/cetak-plastik-ok-56da463b729b7 21/30

)njection "oldin%: ,-piece and .-piece molds 

7/21/2019 Cetak Plastik OK

http://slidepdf.com/reader/full/cetak-plastik-ok-56da463b729b7 22/30

)njection "oldin%:mold den%an core er%erak dan side-action cam 

- +ila bentuk(geometri ada undercuts

7/21/2019 Cetak Plastik OK

http://slidepdf.com/reader/full/cetak-plastik-ok-56da463b729b7 23/30

Cait#Core

/ompo$e$ mold u$tuk /ompo$e$ mold u$tuk 

produk 'a$*kir plastik produk 'a$*kir plastik 

u$$erate

"ole

prue

7/21/2019 Cetak Plastik OK

http://slidepdf.com/reader/full/cetak-plastik-ok-56da463b729b7 24/30

u$$er

Part

Cait#

"ole

Part

Cait#

/$o

(tripperplate

u$$er

Part

Cait#

"ole

u$$er

Part

Cait#

"ole

u$$er

Part

Cait#

"ole

Part

Cait#

/$o

(tripperplate

Part

Cait#

/$o

Part

Cait#

/$o

(tripperplate

u$$er

Part

Cait#

"ole

u$$er

Part

Cait#

"ole

Perancan%an injection mold : mold in action

[source: Lec notes, Prof T. Gutosky, MT!

7/21/2019 Cetak Plastik OK

http://slidepdf.com/reader/full/cetak-plastik-ok-56da463b729b7 25/30

Perancan%an injection mold : itur-itur umum

[source: """.i#sa$mp.or%!

7/21/2019 Cetak Plastik OK

http://slidepdf.com/reader/full/cetak-plastik-ok-56da463b729b7 26/30

(a) hut-off hole

no side action re*uired

(b) +atch

no side action re*uired

(c) ,ngled +atch

ide action cam re*uired

(a) hut-off hole

no side action re*uired

(b) +atch

no side action re*uired

(c) ,ngled +atch

ide action cam re*uired

Perancan%an injection mold : itur-itur umum

7/21/2019 Cetak Plastik OK

http://slidepdf.com/reader/full/cetak-plastik-ok-56da463b729b7 27/30

0asar perancan%an produk injection moldin%

asar utama:$i aliran plastik ke seluruh bagian cavity sebelum mengeras$ii penyusutan plastik dalam lubang penyusut

Panduan (1# 

sahakan penampang(ketebalan seragam seluruh bagian produk

ow: use of ribs(gussets

/source: %0 plastics: 1n#ection 2olding esign %uidelines3

7/21/2019 Cetak Plastik OK

http://slidepdf.com/reader/full/cetak-plastik-ok-56da463b729b7 28/30

Panduan (,#  indari penampang yang tebal

/source: %0 plastics: 1n#ection 2olding esign %uidelines3

0asar perancan%an produk injection moldin%

7/21/2019 Cetak Plastik OK

http://slidepdf.com/reader/full/cetak-plastik-ok-56da463b729b7 29/30

Panduan (.#  4okasi gate menun#ukkan weld line

weld lines

' !ource: http:((www.idsa-mp.org(proc(plastic(in#ection(in#ection)des

0asar perancan%an produk injection moldin%

7/21/2019 Cetak Plastik OK

http://slidepdf.com/reader/full/cetak-plastik-ok-56da463b729b7 30/30

eld li$e i$k mark eld li$e i$k mark 

& 'ource: ttp:""" i#sa mp or%procplasticin*ectionin*ection #esi%n tm

eld li$e

&lira$ kedalam Mold

ate

Produk #* suda +adi

i$k mark Pera$'a$*a$ ris u$tuk

memi$imalka$ si$k mark