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When testing exceeds EQ limits

Discussion in 'Capability - Process, Machine, Gage …' started by Neal G., Sep 12, 2019.

  1. Neal G.

    Neal G. New Member

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    Hi there. First time post!

    So, pull test, spec = 20 lbs. Actual values, 100+ lbs. limit of the test gage is 100 lbs.
    Engineer #1 suggests treating it as attribute data, which would require additional samples.
    Engineer #2 suggests recording failure as 100 lbs, which is 5x spec, but does give a false standard dev.

    Excluding purchasing a new test gage, which is $1500, other suggestions or justifications?

    Thanks!
     
  2. Andy Nichols

    Andy Nichols Moderator Staff Member

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    Find a test lab with the right equipment and contract them to do the samples?
     
  3. Miner

    Miner Moderator Staff Member

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    Why do either? Unless you are trying to perform a capability study, you clearly far exceed the specification. If you are trying to perform a capability study, I would then question the need to do so as you again far exceed the specification. If this is internally driven, it should be easy to justify, just document the rationale. If it is customer driven, it will probably be more difficult, but still worthwhile to have the hard discussion with them.

    Another approach would be a variant of Engineer #2's suggestion. Use the standard deviation of a similar product that falls below the 100 lbs. Then you can state that your capability is better than this threshold, which far exceeds the specification.
     
    Bev D likes this.