00193407-02 HWWS SIPLACE Machine Accuracy EN.pdf - 第14页
© Siemens AG . . Änderungen vorbehalten SIPLACE Placement Systems Cm >1.33, Cpk >1.33 Cm <1.33, Cmk < 1.33 Cmk <1.33 Cm >1.33 Cm <1.33, Cmk < 1.33 example: specificatio n 50 um at 4 Sigma Machine …
© Siemens AG . . Änderungen vorbehalten
SIPLACE
Placement Systems
Quality Evaluation
For an evaluation of quality, a comparison with the specifications is necessary.
The specifications determine the upper and lower parameters, which during the process may not
be exceeded.
Each process has a determined set-point value which must be achieved. Each deviation from
this desired value includes additional risks .
centering and dispersion
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dispersion to
high
Cmk < 1.33
(4 sigma)
dispersion good,
centering not good
(offset high)
dispersion good,
centering good.
Cmk > 1.33
(4 sigma)
Cm value equal
the higher the Cm and Cmk, the better
Machine Capability
Machine Capability
© Siemens AG . . Änderungen vorbehalten
SIPLACE
Placement Systems
Cm >1.33, Cpk >1.33
Cm <1.33, Cmk < 1.33
Cmk <1.33
Cm >1.33
Cm <1.33, Cmk < 1.33
example: specification 50 um at 4 Sigma
Machine Capability
© Siemens AG . . Änderungen vorbehalten
SIPLACE
Placement Systems
example: specification 50 um at 4 Sigma (1 sigma = 12.5 um)
C
m
<1,33 C
m
=1,33
C
m
>1,33
dispersion to high,
Sigma > 12.5 um
dispersion normal,
Sigma = 12,5 um
dispersion low,
Sigma < 12,5 um
Machine Capability