Moldflow MPI

CD-ROM

S/N

The mold flow analysis of the injection

molding process using Taguchi method and

grey relational analysis

Abstract

This article makes use of quality engineering program of the Taguchi method and the

grey relational analysis to develop the procedure about the many distinct engineering factors

effect the quality of objective on the injection molding process. We also collocates the mold

flow analytical software of Moldflow MPI to process the mold flow analysis.

Simultaneously, it analyzes and proves the influence of the many distinct engineering factors

on the quality of objective each other, from many experiment result of each engineering

factor's combination, to establish the optimal process of plastics injection molding in order to

execute the effective computer simulation. We take the warping phenomenon of CD-ROM

disk pallet for an example, in accordance with the process of variation of signal to noise ratio

and the grey relation analysis for each engineering factor upon the distribution of shear

stress, acquire that the result for the influences of the objective quality will identically. The

arrangement of effect magnitude is the temperature of melt, filling time, filling pressure and

temperature of mold. From the degree of contribution or relation we obtain that the

noticeable variations are the temperature of melt and filling time. Those factors will increase

the quality of product. The filling pressure and temperature of mold, the unnoticeable

variations, will be the basis to reduce cost.

Key words : Taguchi method, grey relational analysis, signal to noise ratio, degree of relation,

injection of form.Ko-Ta Chiang : Associate Professor, Department of Mechanical Engineering, HIT

[1,2]

(CAE)

(CAE)

C-mold moldflow Moldex

Kamal and Keing [3]

Wu et al. [4]

N o n -

Newtonian fluid Behavior

Hieber and Shen [5]

Hele-

S h a w [ 6 ] N o n -

Newtonian fluid

Chiang et al. [7]

Hele-Shaw[6] Hetu et al. [8]

3D

Pandelidis and Zou [9]

Choi et al. [10]

Neural network

(CAE)

CAE CAE

(try-and-error)

( Ta g u c h i

Method) [11]

1923 R. A. Fisher [12]

(orthogonal array) (signal to

noise ratio, S/N) (analysis of

variance, ANOVA) (response

table) (response graph)

(Taguchi Method)

[13,14]

[15,16]

[17]

( G r e y

system)

[18-22]

[23]

Laing[24] Chang

et. al. [25]

I-deas Master Series 8

Moldflow MPI

CD-ROM

(orthogonal array)

(signal to noise ratio,

S/N) (analysis of variance,

ANOVA) (response table)

(response graph)

(the larger-the-

better ) (the smaller-the-

better ) (the nominal-the-

better )

(

)

S/N S/N

M.S.D.

(the mean square

deviation)

S/N

S / N

Q(X) R

Xi

X0(k) Xi(k) i 0

Xi(k) X0(k)

Xi X0

[18-22]

1.

2.

3.

4.

Xi(k) X0(k)

[18-22 ]

ξ

0 1 0.5 [18-

22]

m i n

max

ri (k)

0.5

ri (k)

Xi Xo

r ( Xo Xi )

CD-ROM

ABS PA-746

187 127 18(mm)

1.5mm 3D

(shear stress)

CD-ROM

1.

2.

3.

ABS

L9

Moldflow MPI

S/N

yi n

S/N

A3 B1 C1

D 1 A 1

B2 C2 D3 S/N

S/N

0.5

Xi

Xo

r ( Xo Xi )

Xo

Xi r (

Xo Xi )

1.2565

S/N

92.64%

4.31%

I-deas Master Series 8

Moldflow MPI

CD-ROM

S/N

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