CPK Z值 PPM关系
当为双规格限时,Z值为超出上规格限和超出下规格限的百万机会缺陷率之和,
Z=PPM(tota)=PPM(USL)+PPM(lsl)=|Z(USL)|+|Z(LSL)|而MIN{|Z(USL)|,|Z(LSL)|}=3*MIN{((USL-U)/3S),((U-LSL)/3S}=3CPK
用EXCEL设定Z值=3CPK,PPM=IF(Z值<4.9~6.1,(1-NORMSDIST(Z值))10000002,(1-NORMSDIST(Z值))1000000000*2)
Z=PPM(tota)=PPM(USL)+PPM(lsl)=|Z(USL)|+|Z(LSL)|而MIN{|Z(USL)|,|Z(LSL)|}=3*MIN{((USL-U)/3S),((U-LSL)/3S}=3CPK
用EXCEL设定Z值=3CPK,PPM=IF(Z值<4.9~6.1,(1-NORMSDIST(Z值))10000002,(1-NORMSDIST(Z值))1000000000*2)
TA的首页

