Revision History, when a parts is given a new number
Revision History, when a parts is given a new number
(OP)
Greetings,
I encountered an issue today and I'm wondering how other places handle this.
I have a part that has been used for long time. It has now been significantly revised in such a way that the form, fit & function have changed. Therefore in accordance with our Technical Data System it must get a new number.
So now I have a new part number for basically an "old" part that has a lot of history. Where would I put the details about what has changed? Would I just fill in the revision block as a rev 0? (we use numerical revision designations, not letters).
Other companies just simply do not worry about it? I know the change details could potentially save us a lot of head-scratching down the road.
On another note; When a part is first created, what "revision" would the drawing be on? Is a new drawing a revision 1 drawing -- so that when it gets revised, it becomes a revision 2 drawing? Or is a new drawing considered a revision "0" drawing -- and after the first revision it becomes a revision 1 drawing?
The system we use is the first example. All drawings start at rev 1 level.(actually its a bit more complicated than that) What do others do?
Thanks,
VS
I encountered an issue today and I'm wondering how other places handle this.
I have a part that has been used for long time. It has now been significantly revised in such a way that the form, fit & function have changed. Therefore in accordance with our Technical Data System it must get a new number.
So now I have a new part number for basically an "old" part that has a lot of history. Where would I put the details about what has changed? Would I just fill in the revision block as a rev 0? (we use numerical revision designations, not letters).
Other companies just simply do not worry about it? I know the change details could potentially save us a lot of head-scratching down the road.
On another note; When a part is first created, what "revision" would the drawing be on? Is a new drawing a revision 1 drawing -- so that when it gets revised, it becomes a revision 2 drawing? Or is a new drawing considered a revision "0" drawing -- and after the first revision it becomes a revision 1 drawing?
The system we use is the first example. All drawings start at rev 1 level.(actually its a bit more complicated than that) What do others do?
Thanks,
VS





RE: Revision History, when a parts is given a new number
If it is not fully interchangeable then it should be a new part number - but interchangeable can go beyond physical factors see ASME Y14.100 section 6.8.
The release document/ECO/rev block whatever can potentially contain a reference to the old PN to get the history.
As to what the initial rev designation should be, it has been discussed here before.
In practice many places do use 'A' as the initial release (ASME only explicitly lists use of letter revisions).
What is Engineering anyway: FAQ1088-1484: In layman terms, what is "engineering"?
RE: Revision History, when a parts is given a new number
Every company I ever worked at, numerical revs are preliminary, alpha revs are released.
The letter "O" is not used, so I would not use "0". It may get confused with the letter "O".
Chris, CSWA
SolidWorks 14
ctopher's home
SolidWorks Legion
RE: Revision History, when a parts is given a new number
RE: Revision History, when a parts is given a new number
"Part released. Formerly part xxxxxx"
RE: Revision History, when a parts is given a new number
vonsteimal is correct in saying that any change to the parts form, fit, or function justifies a new part number. Too bad the US automaker (was it GM or Ford?) didn't follow this practice when they changed the design of the highly publicized ignition switch that caused so many accidents and deaths. My understanding was that one engineer changed the form and function of the switch without changing the part number. Everybody downstream didn't think anything of it when they stocked a part under the same part number but a different form and function. After all, the two versions WERE interchangeable!
Tunalover
RE: Revision History, when a parts is given a new number
What is Engineering anyway: FAQ1088-1484: In layman terms, what is "engineering"?
RE: Revision History, when a parts is given a new number
That's what I said. I said the parts were interchangeable but did not have the same form and function.
Tunalover
RE: Revision History, when a parts is given a new number
From what Tunalover said: "I think a dash "-" should signify the released part with subsequent revisions given letter designations", are most companies tracking both release numbers and rev designations? Where a "release" signifies a minor revision (does not change Form, Fit or Function; i.e. spelling.etc)?
Thanks,
VS
RE: Revision History, when a parts is given a new number
Tunalover
RE: Revision History, when a parts is given a new number
On the new drawing, you can add a note "similar to" to ref the old part.
Chris, CSWA
SolidWorks 14
ctopher's home
SolidWorks Legion
RE: Revision History, when a parts is given a new number
What may change is the approval loop/how many signatories etc. but fundamentally it's still a drawing revision.
As mentioned the ECO/release document for new PN can give a whole bunch of info about the old part if so desired, we sometimes do this were appropriate.
What is Engineering anyway: FAQ1088-1484: In layman terms, what is "engineering"?
RE: Revision History, when a parts is given a new number
Tunalover
RE: Revision History, when a parts is given a new number
I am a huge advocate of the revision block detailing each and every change - too many years of working back revisions to find out why something doesn't work anymore. Otherwise the rev block says 'see ECN" and the ECN says "see rev block"