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【转帖】qa info on drawings

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发表于 2009-4-29 21:35:10 | 显示全部楼层 |阅读模式
qa info on drawings
what is everyone's stance on putting qa information on a drawing.  we have some individuals here that would like to see some qa info on a drawing, and others that think the drawing should not contain information like that.  the qa check for this particular drawing is a test of a circuit to verify proper resistances at certain points.  this gives a quick check of whether there are proper connnections among several components.  i take the stance that information like this should not be on a drawing, but maybe i'm wrong.  what are your thoughts?
any info that does not have anything to do with creating the part should always be a separate doc.
chris
sr. mechanical designer, cad
solidworks 05 sp3.1 / pdmworks 05
in automotive we identify 'key and/or critical characteristics' on the print. these can include safety items, fit or functional items, etc. that must be met (and monitored) for compliance. additional checks (risk management) are applied to these elements. this is the design team's way of speaking to qa.
the program manager (ei: me) will bring together the design and quality teams to address how we intend to treat each characteristic. in your case, apply a resistivity check at 'x' frequency across points a&b within a range of 'tolerance'.
identifying these characteristics on the print throws the flag up for all involved and this is good communication. a proper dfmea is the tool to identify whether a particular characteristic is key, critical or merely an attribute.
*without data, you're just another person with an opinion.*
hydroformer
in the medical device field, i have seen many drawings that had quality requirement as notes on the drawing, separate from the general notes.  i have also seen full-blown inspection or quality drawings made from the fabrication drawings to cover such things.
according to asme y14.100-2000, section 4.26.6 (j)
notes shall not include contractual requirements, such as statements of costs; time and place of delivery; methods of payment; and requirements for submission, approvalfff">, or distribution of data, reports, or plans.
i think there is a world market for maybe five computers.
thomas watson, chairman of ibm, 1943.
hydroformer is correct. key/critical characteristics are ok to show on dwgs. sometimes it is required.
chris
sr. mechanical designer, cad
solidworks 05 sp3.1 / pdmworks 05
on formed 鈥渟heet鈥?parts in the automotive trade it is also common to show the areas where a part will be located for inspection, it can make a big difference.
i never understood the "key/critical" feature concept.
if a dimension needs to be on the drawing to allow the part to be made, then it is necessary - period.  let the qa guys determine what sampling level (both number of parts and features measured on individual parts) they need to ensure the desired level of scrap is consistently produced.
in pdybeck's case, it sound like a test procedure is needed.  in this case i would say that the drawing should contain a note referencing the test procedure.
mintjulep,
     to play devil's advocate... why not just put the test procedure on the drawing if your are going to put a note about it anyway.  what i am getting at is what is the metric you use to decide when to put information on another document outside the drawing?  to everyone else, the same question applies.  why locate inspection reference points on a drawing if as ctopher says "any info that does not have anything to do with creating the part should always be a separate doc."  is it merely for not having to create another document outside the drawing that references the part?  ctopher, do you take your stance b/c now there is extra information that might end up revising the print that has nothing to do with the creation of the part?
pete
pdybeck,
in the current case you have determined that measuring the resistance at a few point is a sufficient check.  a few simple steps.
if your next project is more complicated you might have a dozen steps in your test procedure.
more complicated yet, and you could have a few hundred steps.
at some point is become impractical to do this on the drawing.  where is that point?  any answer other than "the test is a separate document, referenced on the drawing" will result in product-to-product inconsistency in your production methodology.
also,  where do you record that the test has been performed, or for more complex tests, record the actual results and values measured?  where do you record what instrument was used to make the measurement?
mintjulep,
   i agree with you, i was just digging for the reason behind the answer.  thanks for the reply.  maybe hydroformer or ajack1 have a different metric....
one instance i can think of why you wouldn't want a test procedure on a print is revision control.  if the test engineer wants to revise the test procedure then the drawing has to be revised.  if the test procedure number is called out on the print then the current rev is used.  
we call out the document numbers to test procedures (atps), and procurement specifications.  it just makes of better document control.
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