统计过程控制106

1、SPC的发展史

2、基本统计概念

3、过程变差

4、控制图

5、过程控制和过程能力

20世纪20年代，美国休哈特提出；

二战后期，美国将休哈特方法在军工部门推行；

1950~1980，逐渐从美国工业中消失 ；休哈特的同事戴明博士在日本推行SPC；

在日本强有力的竞争下，80年代起，美国又重新大规模推行SPC；

美国三大汽车厂联合制定QS9000标准。

1、确保制程持续稳定、可预测。

2、提高产品质量、生产能力、降低成本。

3、为制程分析提供依据。

4、区分变差的特殊原因和普通原因，作为采取局部措施或对系统采取措施的指南。

Imagine for one brief moment that each of the one hundred and forty-one words of this paragraph is a separate component from a first run of fourteen-inch flywheels. You are one of five inspectors performing the final inspection of these finished components which were produced on fairly small dial index machines that are not being controlled by the use of statistical techniques. As can be expected from an operation of this nature , there are a number of defectives components being made .Each word that contains an f represents a defective component. How many of the defectives are you able to find? Check again and inspect for the present ’s off ’s. Write your final count in the bottom left hand corner of this page .This example should give you a fair idea of how reliable 100%inspection can be.