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Cpk For 0201 Placement

#32322

Cpk For 0201 Placement | 28 January, 2005

We were talking to a placement machine sales-type the other day. He stated that the Cpk for placing 0201 was 1.33 [Cpk = 1.33, Sigma = 4, DPMO = 6210]. What do you think?

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#32325

Cpk For 0201 Placement | 28 January, 2005

I think you should talk to the placement machine engineer type.

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RDR

#32326

Cpk For 0201 Placement | 28 January, 2005

Maybe this number is only for the ones that actually got placed!? Like, we had a 15% pick error rate but the ones that did make it were great!

So the 1.33 CPK was in regards to what parameter/specifications? accuracy, pick error, or what?

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KEN

#32333

Cpk For 0201 Placement | 29 January, 2005

I recently ran a process evaluation (Print/ P&P /Reflow) and was plesently surprised with a 5.0 sigma process or 250ppm. Attrition was under 1%. Keep in mind this is defects counted Post-reflow. The most signifficant defect was tombstoning / draw-bridging.

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#32335

Cpk For 0201 Placement | 31 January, 2005

Dave-

Excuse the shameless self promotion but we market a product that does just what you are referring to...measuring Cp and Cpk levels on SMT equipment. If you've ever had the desire or need to gather this data on your in-house SMT equipment please take a look at our web-site for more information.

www.timekeysolutions.com

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#32344

Cpk For 0201 Placement | 31 January, 2005

These guys http://www.cetaq-americas.com/index.shtml have the CmController that can do the measurement to back up the p&p vendor's claim. A CpK of 1.33 ain't bad. Would like to see 2.0. The picking is critical too. Ask vendors for pick accuracy and repeatability data.

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