Pertanika J. Sci. & Techno!. Supplement 12(2): 85 - 99 (2004)
ISSN: 0128-7680
© Universiti Putra Malaysia Press
Design and Simulation of Plastic Injection Moulding Process
Wong, C. T., Shamsuddin Sulaiman, Napsiah Ismail & A.M.S. Hamouda
Department of Mechanical and Manufacturing Engineering
Universiti Putra Malaysia, 43400 UPM, Serdang, Selangor, Malaysia
E-mails:choontat@tm.net.my.suddin@eng.upm.edu.my.napsiah@eng.upm.edu.my.
hamouda@eng.upm.edu. my
ABSTRAK
Kertas ini membentangkan proses reka bentuk satu acuan suntikan plastik untuk
menghasilkan satu produk. Ia dibahagikan kepada tiga bahagian iaitu: bahagian reka
bentuk, bahagian simulasi dan bahagian analisa. Plastik produk ini direka bentuk kepada
dua bentuk yang berlainan tetapi mempunyai fungsi yang sama iaitu satu produk
menggunakan fungsi klip dan satu produk lagi menggunakan fungsi lekat. Untuk Reka
Bentuk Terbantu Komputer (CAD), perisian komputer yang digunakan untuk meraka
bentuk produk dalam 3 dimensi (3D) dan acuan ialah Pro/Engineer (Pro/E). Dua
plastik produk yang berlainan akan direka bentuk dalam inse:rt yang boleh ditukar-tukar
di dalam satu acuan untuk menghasilkan dua produk yang berlainan. Untuk Pembuatan
Terbantu Komputer (CAM), Pro/Manufacturing (Pro/MFG) daripada perisian komputer
ProlE digunakan untuk menjanakan beberapa kod kawalan berangka untuk proses
pemesinan. Analisis terhadap pengaliran cecair plastik dijalankan dengan menggunakan
perisian (MoldFIow - Part Advisor version 4). Daripada anal isis ini kedudukan tempat
suntikan, suhu bahan dan tekanan suntikan dapat ditentukan. Jangkaan kecacatan
produk seperti weld lines dan udara terperangkap juga ditemui dan dianalisis.
ABSTRACf
This paper presents the design of plastic injection mould for producing a plastic product.
The plastic part was designed into two different types of product, but in the same usage
function. One part is using clip function and another part is using tick function. In the
computer-aided design (CAD), two plastic parts were drawn in 3 dimension (3D) view by
using Pro-Engineer (Pro-E) parametric software. In the computer-aided manufacturing
(CAM), Pro-Manufacturing from Pro-E parametric software was used to develop the
machining program. For mould design, the product was designed into two changeable
inserts to produce two different types of plastic product in one mould base. Before
proceeding to injection machine and mould design, this part was analysed and simulated
by using Mold Flow or Part Advisor software. From the analysis and simulation we can
define the most suitable injection location, material temperature and pressure for
injection. The predicted weld lines and air trap were also found and analysed.
Keywords: Changeable insert mould, injection pressure, air traps, injection location,
mould design
INTRODUCTION
Nowadays, the technology of the tool and die fabrication in plastic injection is one of
the world's fastest growing industries. Plastic is now used in almost every application,
ranging from household articles to space travel, from transportation to packing, from
medicine to toys, from bridge building to sports. Generally, injection moulding is a
process that forms the plastic into a desired shape by melting the plastic material and
forcing the plastic material under pressure into the mould cavity. The shape of the
plastic that is desired is achieved by cooling in thermoplastic or by chemical reaction for
thermosetting.
Mould design and fabrication is a costly and high technology process because it uses
science-based computer-aided engineering (CAE) software to analyse and simulate the