Drawing and Model Revision - Matched or Don't Care???

[ptc-680841]

Windchillers, I am wondering how companies are handling drawing and model revision numbers/letters... MATCHED REVISIONSDo you require that the drawing and model have the same revision? In the example below, both the part and the drawing are at Revision A. The logic here is that it is easy for someone to look at the drawing and realize they need rev A of the model. It makes sense, but might be more work in some cases to keep this synch'd up. 12345.drw A.1, Released12345.prtA.6, Released DON'T CAREOr, do you allow the drawing and the model to have different revisions? The logic here is that it is theDrawing Revisionthat shows up in the Title Block,not the part revision so why worry about it.Also, PDMLink knows which version of the part goes with A.1 of the drawing, sothe usersdont need to be bothered with keeping them synch'd. 12345.drw A.1, Released12345.prt1.2, Released Any feedback is appreciated! Andy B.

[HugoHermans]

Hi Andy,

Our revisions match, mainly for historical reasons. But our title block has both revisions, model and drawing. This to be ready to allow the drawing to be revised without changing the model.
I discussed this with Purchasing and Manufacturing. Both saw opportunities in this approach, and little risk to problems. But we didn’t implement it yet, there are always other priorities.

Met vriendelijke groeten, Best Regards,

Hugo.

[RandyJones]

On 12/20/11 10:17, Andrew Burke wrote:
> Windchillers,
> I am wondering how companies are handling drawing and model revision numbers/letters ...
> *MATCHED REVISIONS*
> Do you require that the drawing and model have the same revision? In the example below, both the
> part and the drawing are at Revision A. The logic here is that it is easy for someone to look at the
> drawing and realize they need rev A of the model. It makes sense, but might be more work in some
> cases to keep this synch'd up.
> 12345.drw A.1, Released
> 12345.prt A.6, Released

This is us. We require matching rev's.
In our case I could see confusion if they don't match.
"What do you mean the model is not the same as the drawing?"
"What is a model?"
"Isn't everything a drawing?"

> *DON'T CARE*
> Or, do you allow the drawing and the model to have different revisions? The logic here is that it is
> the Drawing Revision that shows up in the Title Block, not the part revision so why worry about it.
> Also, PDMLink knows which version of the part goes with A.1 of the drawing, so the users dont need
> to be bothered with keeping them synch'd.
> 12345.drw A.1, Released
> 12345.prt 1.2, Released
> Any feedback is appreciated!
> Andy B.
>


--
------------------------------------------------------------------------
Randy Jones
Systems Administrator
Great Plains Mfg., Inc.
1525 E North St
PO Box 5060
Salina, KS USA 67401
email: -
Phone: 785-823-3276
Fax: 785-667-2695
------------------------------------------------------------------------

[MikeLockwood]

Important to think thru this carefully and establish procedures for all cases.


- Fairly straight-forward for one model on one drawing.

- More options for tabulated drawings, where one drawing defines multiple models of for example a family table, each of which may have a different Revision.

- May also have many models on a drawing of a single part if various models are created with various orientation / positions (e.g. tubing or cables or cardboard boxes or pieces of tape or whatever). Need to manually keep all the models at the same Rev.

- May also have reason to change drawing notes without touching the model; need a decision to revise the model or not if only the drawing needs to be changed.

[MikeLockwood]

One other major consideration…

From a printed drawing, you cannot tell what model is:

- Driving the title block values

- Providing the geometry shown

- Driving any parametric note values

We do as many others – include a parametric table in the .FRM that lists the Revision AND Iteration of the drawing’s primary model.

Consider this
Create and check in 12345.prt, resulting in 12345.PRT, A.1 (bracket)
Create and check in 12345.drw, resulting in 12345.DRW, A.1, (showing 12345.prt A.1)
Check out / in 12345.prt, resulting in 12345.PRT, A.2 (add a hole to the bracket)

Search for 12345.DRW, A.1, add to workspace, open in Pro/E.
If Latest is selected, drawing A.1 shows bracket with a hole
If As Stored is selected, drawing A.1 shows bracket without a hole

Now, decide the bracket needs to became a family table. Create and check in 12346.prt, resulting in 12346.PRT, A.1 (bracket)
Add this model to the drawing and (just for fun), make it the primary model. Result: 12345.DRW, A.2, (showing 12346.prt A.1)

And on and on it goes…

Fortunately, if you strictly do business on published viewables (as we do), you can rely on publishing to publish AS STORED, which ignores anything done to models after the drawing was checked in.

[patrick.chin1]

In my experience as an aircraft engineer in Bombardier and implementing Windchill for the past 17 years, CAD models and drawings do not need to have the same revision. Actually it is best practices not to have the same revision. Instead place the revision of the CAD model in the drawing. Aslo, CAD models are 3D documents. 3D CAD models should not be treated as parts. Non-geometric or cosmetic changes (i.e. Layers, addtional points, colours) in models should not result in a change in drawing and visa-versa. A text change that is not functional (i.e. spelling mistake) should not result in a revision in the CAD model.

Icompletely agree with Mike Lockwood, that 1 model to 1 drawing.I believe that is the best process. Not may would agree, but there is so much less drastic effect in a change notice and the rest of the business cyccle beyond engineering.

What you don't want to occur is mass cascading changes. I agree that engineering always use latest, but the understanding is that engineering works to the latest design. On the other hand, manufacturing and the rest of supply chain works to a specific effectivity of both parts and documentation. Even documentation have different effectivities than parts because there is a lag when drawing could actually reach the manufacturing shop floor locally and in global subsidaries.

What you don't want is the change notice business process to be burden with releasing tons of CAD models and drawings for just one CAD model or drawing change. Due to sychronizing CAD models and drawings results change notice process becomes CAD methodology centric. If CAD methodology centric, most business avoid using WTPart, change management and implementing other CAD tools (ECAD, arbortext and so on) in one solution. Windchill is just used as a Pro/I replacement and not an enterprise solution.

That's what I've seen the past 17 years,

Patrick

[ptc-5248439]

I think Patrick has just touched on an essential element to this question.
Today - with the advancement in electronic data management, what are we really trying to control - drawings or part numbers? I am not necessarily talking about CAD models vs. drawings. I am thinking even more fundamentally. What do we build? What do we configuration manage? What do we put into stock? Parts (and assemblies) - controlled by part numbers, not drawings. This is more evident when we look at ERP. ERP systems manage information by part number, not by drawing number. Integration of PDM to ERP is typically through part numbers. So PDM systems should be configured to manage parts / part numbers first and foremost, not drawings. The drawing is simply the documentation that describes the part in engineering terms.

Windchill / INTRALINK can be configured to manage part numbers first, with drawings being a secondary artifact. Even Revision control is manageable to CM standards. That is why a unique item version is determined by Revision and Iteration. If I need to change layer, color, etc., then I do that by checking in at the current Revision. For "Released" objects, I just need a distinct process for Rev vs. non-Rev changes.

If you accept the premise that the part number is the item that is most important to rev control, then the question is just how do you want to control the drawing. And there is no one right answer. If the drawing number is identical to the part number, then it makes sense to keep the revisions in sync, just to avoid confusion. If there is a distinction between the part number and the drawing number (for instance the drawing is A12345 and the part is A12345-001), then it is more arbitrary whether or not the drawing and part have the same revision. As a side note, if this scheme is used, it is easier to change a single model drawing to a tabulated drawing with changing the number or rev of the original part. One item that I have not seen updated in industry standards is specifying part revision on a drawing as a requirement. If we are going to manage by part number instead of drawing, then the standards need a provision for specifying the revision of the part on the drawing.

MIke


Michael Mongilio
Engineering Applications Manager
ATK Aerospace Systems, Beltsville, MD

[dpaulucci]

Our current business model supports 1 to many tabulated parts on a drawing. We currently separate the wtpart revision from the drawing revision. We also allow individual part revisions within thetabulated series of parts. The part revisions and drawing revision typically are not in sync, no requirement for that.

We also have to customize our BOM information from the wtpart bom, with the item balloon information automatically created in our drawings, trying to leverage core proe functionality ballooning/bom capability....