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Re-validate or not?

Discussion in 'Manufacturing and Related Processes' started by AndyH, Feb 12, 2016.

  1. AndyH

    AndyH Member

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    I'd just like to confirm the requirement to re validate a component we design and have manufactured. This is a fairly expensive process to go through so for this change I'd like to double check - my feeling is that we should.

    The component is a rotor that, during assembly, has a filler placed to help retain position of the subassembly. It has no real structural use outside of this as other features provide the structural integrity. Annoyingly the filler adhesive, which is used in very small quantities has been made obsolete so we have to replace it with an alternative - should the entire rotor now be revalidated with the new adhesive filler or not? It's circa £250k for the pleasure. In the meantime we're buying up old stocks but it has a short shelf life so not something we can put off forever.
     
  2. James

    James Active Member

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    I'll be curious to see this conversation. We have a customer that requires a first article every time they have a blueprint number change, this can include assembly components and thus the complete assembly. I doubt their non-dimensional testing costs are very much at all though, and of course the dimensional checks are minimal. My gut is to check it, but I don't have experience with that kind of costly testing. Do you all have testing facilities that test or prototype things like this before they are approved for production?
     
  3. BradM

    BradM Moderator Staff Member

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    Forgive me in advance for responding to questions with questions... :)

    Are there contractual, industry or regulatory guidelines in play here?
    Do you have a procedure that specifies what type of "change" requires no change, informal/formal Change Control, partial testing, or full validation?
    Do you have a requirement to have customers approve these level of changes?

    Has there been any abbreviated/full level of testing performed to verify the filler is equivalent to the older filler?

    Lots of questions, I Know. But unless this type of "change" has already been agreed upon, I could see (if I was the customer) the value in testing that the subassembly does not wobble/shimmy/ rattle/ develop stress fractures/ etc. from the new filler. :)
     
    Ganesh Sundaresan likes this.
  4. AndyH

    AndyH Member

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    Ah good, this is what I need - a bit of questioning! There's a good basis for the argument to recheck and re-validate ANY change to this part. It rotates at serious speed and as such has the potential to have catastrophic failure. That said, this particular element could be argued that it is not required at all which is why I'm scratching about to be certain. We can do basic tests but not the full suite of tests that are required to fully validate. Which is a pain!

    Brad - contractual requirements, no. industry entirely possible but it's a part that goes into several industries (any one definitive requirement would be sufficient for me) and no applicable regulatory requirements have been identified yet; in fact I guess this is what I'm after either from automotive or aeropace inductries. No procedure exists. As mentioned this is very much a start up and they're hopeless with quality (seriously awful!) and frankly I need to train them from scratch. The new owners however <may> have something but are likewise not very hot on this. This is something I shall chase after...
    This isn't being driven by a customer change otherwise they'd be paying and I'd be very happy :) This product goes to many customers so no single entity could approve for all hence it rests with us.

    New filler is stated as the equivalent - part of the process would be to assess is it actually is adequate as a replacement.

    I'm feeling this is very much an element we have to define internally if it is required or not. I'm guessing most would err on the side of caution and have it revalidated although I'm still loathed to do it so looking for an out as long as we can do adequate other testing to show replacing the filler will not compromise safety or performance.