Weld backing bar modeling issues

[CorieYoung]

Hi there - I sure hope someone can provide me with some insight on how they handle this situation...

We design and build large welded assemblies - mostly from steel plate.  Some of our welds require backing bars to be used.  The request is to see a total number of linear feet of each type of backing bar used in the assembly in the BOM - not X number of pieces cut this size and X number cut that size...

It seems to be a simple enough solution to not model the backing bars (which would require unique part numbers for each unique size) and to just add a line item at the end of the BOM with a hand-calculated length for the backing.  But this solution creates a few other issues:

     a) possibility of the calculated length to be incorrect

         since it's not derived from the model, and

     b) the backing strips are not modeled and added to

         the total weight of the assembly.

Or should the backing bars be treated as a consumable (the way the welding rod is) and not show it in the BOM, only noted in the tail of the weld symbol?

This could go any way I guess.

How do other companies handle this situation?  Any input would be greatly appreciated.

[blair]

1.) You could create a new IAM file and place the weldment in the file and then use the CC to create your flat-bar backing bar as well as it's placement. You can then add the QTY column to your BOM in your IDW with will give you the number of pieces, each length and the total length. It won't get you the total length of a given shape but it will help.

2.) Just treat it as a consumable since they will be discarded in most cases and end up in the scrape bin.

We will do it both ways, for our own standard production, we just consume the backing bar in our ERP system (guess the shop has done the parts long enough and enough of them not to require drawings). For any custom "On-Off" work, we create "weld" drawings for things such as backing bar.