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, 12 3 , 2018J. Korea Society of Die & Mold Engineering, Vol.12 No.3, 2018 ISSN 2092-9692

- 1 -

(Injection Blow Molding, IBM)(preform)

. 2. , 1

(single-stage blow molding, SBM)

. 2(two-stage blow molding, TBM)

1. :

E-mail: bscha@kitech.re.kr

(stretch)1). 2

1

.

.

. Schmidt et al. (visco-elastic)

2).

1,

Finite element analysis of a injection blow molding processfor the thick-walled PET bottle

Seok-Kwan Hong Min-Jae Song Young-Bae Ko Baeg-Soon ChaKorea Institute of Industrial Technology, Molds & Dies R&D Group1,

(Received October 30, 2018 / Revised November 22, 2018 / Accepted December 01, 2018)

Abstract: Plastic containers which provides the opportunity to reduce transportation costs are lighter and less brittle than glass containers. As a results, efforts to replace glass with plastic are ongoing. The blow molding method is a typical approach in producing plastic containers. Single-stage injection blow molding (ISBM) is one of the blow molding methods. However, the difficulty in controlling the temperature during the injection molding process is considered its main disadvantage. In this study, ISBM process analysis of relatively thick walled containers such as cosmetic containers is carried out. The initial temperature distribution of the preform is deemed to be the most influential factor in the accuracy of blow molding for the thick vessel. In order to accurately predict this, all heat transfer processes of the preform are considered. The validity of this analytical procedure is verified by comparing the cross-sectional thickness with the actual product. Finally, the validated analytical method is used to evaluate the factors affecting the thickness of the final molded part. The ISBM analysis technique for thick walled vessels developed through this study can be used as an effective predictor for preform design and blow process.

Key Words: Blow molding, FEM, Injection molding, ISBM

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- 2 -

Wang et al., (visco-plastic)

3D TBM , 3). Yang

et al. glass rubber model TBM ABAQUS

4).

. Haessly and RYAN (hyper elastic)

5). .

Pham et al PET(stain rate) biaxial stretching test

6). (visco-hyper elastic) TBM

3 BLOWSIM . Cosson et al

microstructure evolution (simple visco-plastic)

(molecular orientation) (crystallinity). free blow

7). McEVOY et al. TBM ABAQUS

8). Shell solid .

(elasto-viscoplasticity). Chung ABAQUS

9). TBM (elasto-viscoplasticity)

. Debbaut et al. HDPE(viscoelastic fluid)

310). (parison)

. Biglione et al. SBM POLYFLOW PP Cross

11). . Gupta et

al. PET 2D

12). (cosmetic glass container)

STM .

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. SBM

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(mapping) .

SBM Fig. 190

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. 85ml 2

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Products PETG . PETGPET

sheet CHDM (1,4-cyclohexanedimethanol)

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270 , 20 , 80% , 4 .

1.7 . Table 1.

Conditions Value

Mold temp 26

Melt temp 260

Injection time (sec) 1.7

Packing control methodtime (sec) 4

ratio (%) 80

Cooling time (sec) 46

Fig. 4. PET

208 ,

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(mapping) . Fig. 5 32D-

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Description Value Unitn 0.1926τ* 563860 Pa.D1 9.9606e11 Pa.sD2 355.8 KA1 26.554A2 51.7 K

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Fig. 6. (gate cutting)

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(bottom core)

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.

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