考慮製程能力指標之允收抽樣計劃

摘要

一般的計量值允收抽樣計劃大都是以製程參數（通常是平均數）或製程不良率作爲允收或拒收送驗批之品質要求，而製程能力指標則是用來衡量供應商是否有能力製造出符合規格之產品的一個量數，在採購契約中通常是以製程能力指標作爲買賣雙方對品質要求的依據。因製程能力指標是製程參數或不良率的函數，故亦可用其作爲判斷送驗批合格或不合格的標準，因此本文的主要目的即是發展出以製程能力指標C _P 、CPU及CPL爲品質要求的規準型單次計量值允收抽樣計劃表，並以實例說明此表之使用步驟，以供實務界參考使用。

Abstract

There are two general types of variable sampling plans: plans that control process parameter (usually the mean) and plans that control process fraction nonconforming. Process capability index (PCI) is a function of process parameter and nonconforming fraction and it measures the ability of the process to manufacture products that meet specifications. Therefore, PCI can be used as a quality benchmark for acceptance of a lot of products. This paper developed single sampling plans schemes based on process capability indices C ^p1, CPU and CPL. Several examples are given to illustrate the proposed sampling plans for practical use.

關鍵詞:

• 製程能力指標
• 允收水準
• 拒收水準
• 抽樣計则
• 非中t分配

Keywords:

• process capability indices
• acceptable quality level
• rejectable quality level
• sampling plans
• noncentral t distribution