Specifying revision levels of component parts on assembly drawings

[McLeod]

Looking for opinions on a drawing practice related to configuration management: including revision levels of component parts on an assembly drawing. The standards and drafting guidance documents don't seem to directly address it. Advisable or not? How about if the configuration management system also includes a separate parts list which lists revision levels?

 

[MadMango]

Our products make heavy use of configurations. For our assembly drawings, we do not provide a parts list, just a note telling people to refer to the BOM in our ERP system. We do not rev our top-level assembly drawings, or any of our BOMs.

Not sure if that helps or not.

[green]"Art without engineering is dreaming; Engineering without art is calculating."[/green]

Have you read faq731-376 to make the best use of Eng-Tips Forums?

 

[MintJulep]

Generally a bad idea for the quite obvious reason that it forces you to revise all higher-level drawings when any lower level drawing is revised.

A robust configuration management system needs to be able to do more than can be done on an engineering drawing. It should, for example, be able to tell you the rev levels that were current at the time of production for every serial number built, and answer compatibility questions about what changed with each revision of each drawing. With that information you can make a decision if you ever need to make a replacement part for any serial number. Do I have to produce a replacement to an earlier rev, or will the current rev work?

The CM system should also tell you about things like software versions installed, modifications made, production test and inspection results, and the names of everyone that worked on the equipment.

 

[KENAT]

Don't put it on the parts list, especially if it's a parts list on the face of the drawing.

If you need to document it outside of the ERP/MRP/PLM/PDM whatever software I suggest using what in the UK is a Drawings list, the closest in the US is I believe a Data List. This may be what you mean by "separate parts list which lists revision levels?" though is slightly different from a parts list.

The drawing list generally just lists the Drawing numbers and their rev for the top level assembly.

If this is of interest I could explain more.

 

[ctopher]

It's very rare to see "Data List" here in USA, but has been done.
Normally there will be an assy dwg that will ref a Parts List (PL) that lists all parts & materials for the assy. Each part on the PL will have its own revision and the PL will have its own rev (separate from the dwg).
Each company does it different. Whatever works for you. If you do any kind of gov't work, your system's documentation has to be traceable back in history.

Chris
SolidWorks 06 5.1/PDMWorks 06
AutoCAD 06
ctopher's home (updated 10-27-06)

 

[ewh]

For more on this subject, see thread781-124063

 

[CheckerRon]

Revision levels on assembly drawing parts list is a BAD idea for all the reasons noted by the previous respondents.
A Data List IAW ASME Y14.3-1996 is a tool basically meant for Configuration management use, and is intended to track current revisions of drawings and documents. It may be rare in the commercial world, but mandated in MIl spec work. It's a good thing, and I would lobby your CM group (if you have one) to consider using this instead of sticking the revisions on the drawings, where they don't belong.

 

[ctopher]

Just want to be clear ... I meant a "separate" PL showing revs, not lsited on the dwg.
Thanks ROn, I didn't realize what I had written.

Chris
SolidWorks 06 5.1/PDMWorks 06
AutoCAD 06
ctopher's home (updated 10-27-06)