DEK高级培训资料.pdf - 第213页
Cp Cp = T OLERANC E RANGE P A TTERN WIDTH = T OLERANC E RANGE 6 x stdev = 24 12 = 2Cp = 0 -12 12 0 = 2 Process Capability example Issue 2: July 2007 6 x stdev 12 SIGMA SIGMA = SPECIFIED LIMIT ST ANDARD DEVIA TION = 12 …
Cp
Cp =
TOLERANCE RANGE
PATTERN WIDTH
=
TOLERANCE RANGE
6 x stdev
Process Capability Formula
Issue 2: July 2007
SIGMA
SIGMA =
SPECIFIED LIMIT
STANDARD DEVIATION
SIGMA =
0.5 x TOLERANCE RANGE
1 x stdev
Cp
Cp =
TOLERANCE RANGE
PATTERN WIDTH
=
TOLERANCE RANGE
6 x stdev
=
24
12
= 2Cp
= 0
-12
12
0
= 2
Process Capability example
Issue 2: July 2007
6 x stdev
12
SIGMA
SIGMA =
SPECIFIED LIMIT
STANDARD DEVIATION
=
12
2
= 6 SIGMA
6 SIGMA @ 12 = +/- 6 SIGMA @ +/- 12
-12
12
0
Cp
Cp =
TOLERANCE RANGE
PATTERN WIDTH
=
TOLERANCE RANGE
=
24
= 2Cp
= 2
= 8
Shifted Process Capability (Cpk)
Issue 2: July 2007
=
TOLERANCE RANGE
6 x stdev
=
24
12
= 2Cp
12
-12 0
Dist. from Mean to nearest Limit
3 X Stdev
Cpk =
=
4_
6
= 0.66 Cpk
Cpk