PPM
PPM stands for ‘parts per million’ and refers to a parameter that indicates the number of defective parts per million parts examined. PPM is therefore used to evaluate and compare defect rates in series production.
A low PPM value indicates a low defect rate. However, for a meaningful assessment, the underlying defect characteristics, test conditions and quality requirements must always be taken into account.
At MN Kaltformteile, defined quality characteristics are monitored throughout the manufacturing process. Depending on the component’s requirements, various inspection methods are employed, including automated 100% inspection.
PPM in quality assurance
In large-scale series productions, even a small number of defective components can be significant. Expressing figures in PPM makes it possible to compare defect rates independently of the absolute production volume.
MN Kaltformteile employs various inspection and quality assurance procedures. These include, amongst others, dimensional inspections, surface analyses and strength tests. For particularly demanding components, 100% sorting using optoelectronic inspection technology is also available.
With a suitably designed camera-based 100% inspection, MN Kaltformteile can achieve a residual defect rate of ≤ 10 ppm per sorting criterion for defined sorting criteria.
PPM serves as a key figure for describing defect rates in series production. For sorted components, a defined residual defect rate can also be agreed. This must always be considered in conjunction with the defined inspection criterion and the inspection or sorting methodology employed.
PPM: Questions and answers
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What does PPM mean?
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What does a low PPM value indicate?
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Why is PPM used in series production?
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How can low PPM values be achieved?
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What residual defect rate does the 100% sorting of MN cold-formed parts achieve?
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How is the PPM value calculated?