From: "Michaels, David J" DMichaels@newcor.com
To: forum_mail@16949.com
Subject: QS 9000: 4.20 - s.p.c
Date: Wed, 20 Sep 2000 10:48:39 -0400

Is using s.p.c. for economic reasons (savings in material usage ), as opposed to product / specification control reasons required to meet a 1.33 CpK minimum?

Specifically, our processes are component-dominant ( if the molds are manufactured correctly all produced parts produced meet spec. ) and set-up dominant ( 1st part meets spec. = all meet spec. ). We monitor part thickness on an X bar / R chart, with a goal of producing parts that are not too thick / heavy. Is this control subject to QS 9000 requirements? Thanks!

Dave M.

It sounds like you are checking thickness as a means of monitoring process variation in your molding process that relates back to material usage. I think this would be a good example for showing compliance to Elements 4.9.2 and Element 4.2.5. Is product weight or thickness a characteristic covered within the PPAP documents?

Dear Marc,
As it appears, in your case the SPC is being implemented for economic reasons and not for customers specifications.

However, as the basic intent, SPC has to be focussed in a major way on cost reduction & reduction in variations in all cases economic reasons would be the major objective of such studies.

For the sake of this question..Say
If for whatsoever reasons we have implemented SPC studies, then...

We have identified the need for SPC...

We require to implement it...

We MUST ensure that the related people are
knowledgable about the basics and ralated requirements...

We have to keep records of the study to analyse it...including the significant process events..

And so on.

And we have to have all this stuff with us!

FURTHER..APPLICATION OF 4.20 IS NOT RESTRICTED TO ONLY CUSTOMER SPECIFIC SPC AND PARAMETERS..

Thanks

e.s.deo