S. Udhayha Kumar said:
What is the relationship between the error in stability, linearity of the measurement system with respect to acceptance / rejection of parts? Could some one enlighten me with some example showing the relationship?
σ2cAPABILITY=σ2BIAS(Lineality)+
σ2(GRR ) MSA tHIRD EDITION PAGE 57
σ
2(GRR )=σ2(REPRODUCIBILITY) +σ2(REPETEABILITY ) MSA PAGE 55
tHEREFORE page 58
σ2(performace)=σ2(CAPABILITY )+σ2(STABILITY )+σ2(CONSISTENCY )
CPACT=CPOBS/SQR(1-(cPOBS*GRR)^2) msa page 192
This is the relation of GRR MSA and Cp (Process)
If Cp>1.67 -> 2,3 ppm.
Stablish a criteria of Cp.
But the real Cp is affected by the GRR with the formula given.
So you meassure your Cp, lets say 1.65. Caution,
The real Cp, Cpact is less just apply the formula.
msa created in Page 191 the relation between GRR and Cp,
but σ2(performace) with Cp it is not done by MSA.
You would need to follow the same procedure to obtein the relation.