田口方法應用於EPS發泡式押出成型參數最佳化

EPS Extrusion Parameters Optimization Using Taguchi Method

邱慧珊(Hui-Shan Chiu)

指導教授 ： 林維新

國立虎尾科技大學/工程學院/創意工程與精密科技研究所/碩士(2010年)

摘要

塑膠押出成型是目前最常使用的成型技術，在工業上為了進行最佳加工參數的設定，常常需要進行繁多的實驗來得到數值，再配合工程師的經驗判斷才能確定參數的設定，而這調整參數的過程並沒有理論根據來分析，既費時亦浪費生產成本，並不合乎經濟效益，因此本研究提出以田口方法，來探討製程參數組合的最佳化。

利用田口方法尋找出影響品質特性之押出成型參數。故列出影響EPS發泡式押出成型最關鍵的八個控制因子–塑膠原料比例(代號A)、冷卻頭溫度(代號B)、冷卻筒溫度(代號C)、模頭第一區溫度(代號D)、模頭第二區溫度(代號E)、瓦斯泵轉速(代號F)、第一押出螺桿轉速(代號G)、拉皮機線速度(代號H)共八個主要控制因子，其八個主要因子除塑膠原料比例為二水準外其他因子各依三水準，進行田口的L18直交表規劃實驗設計，利用各樣本S/N比及變異數實驗分析結果，得到押出成型參數對品質特性最佳組合，其收縮率之改善如下：

1.體積收縮率之改善可有效評估產品瑕疵。
2.適度改變加工參數，如螺桿轉速、拉皮機線速度等，發現可有效改善體積收縮不均問題。
3.經由田口式分析最佳組合之加工參數，可獲得最佳均勻體積收縮率。

關鍵字

田口方法 ； EPS發泡 ； 押出成型 ； 收縮率

並列摘要

Plastic extrusion is the most common technology in plastic industry. To obtain the optimum parameters, we need lots of experiments and experiences to get the value; however, doing experiments take lots of time and even if they ere done, there is theoretical basis to analyze them. Hereby, the purpose of this study is to find out the optimum parameters by using Taguchi Method.

We found out the factors affecting the quality of PS extrusion by using Taguchi Method. The major factors to affecting PS extrusion process are as below:(A)Proportion of plastic material, (B)Cooling head temperature, (C)Cooling can temperature, (D)Die Zone 1 temperature, (E)Die Zone 2 temperature, (F)Gas pump RPM, (G)Primary screw RPM, (H)Pull Roll line speed (Experiment: A in 2 level, B~H in 3 level),This experiment using Taguchi L18 orthogonal array, the analysis of samples S/N ratio and variance obtain the optimum parameter for extrusion. The shrinkage improvement is as following:

1.The improvement of volumetric shrinkage could effectively evaluate the defects on the product.
2.Appropriately adjust the control factors could improve the volumetric shrinkage problems.
3.By means of Taguchi method analyzes the best combination of parameter could get the best volumetric shrinkage ratio.

並列關鍵字

Taguchi Method ； EPS Foam ； Extrusion ； Shrinkage

參考文獻

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