If there are no transactions, you can delete all of the inventory parts and then change it on the Master Part and recreate the Inventory Parts.  But if there is even one transaction in one site, then it is locked and you have to make a new part.

@ShawnBerk   I suspected that was the only option but I wanted to check to make sure.

Thank you!

Another option I have seen is creating a new part with this UoM “Case”. Then change the Part Status of the existing part to Inactive, so it will become unusable and users will not mixed it up.

If you want to go further you can set this new part as an Alternative part to the existing one.

Of course, there are pros and cons in this approach, you may decide based on your business practice :)

I also had the same issue and found the act of deleting an Inventory Part to correct the wrong UOM is also irreversible when the part has no Transactions against it but it has a Buildable Product Structure.

The Buildable Product Structure cant be deleted, meaning the Revision and the Inv Part cant be deleted, So it’s a new part number required in this scenario too.

I’ve never known anyone to use it, but if you are creating a new part to replace one for which transactions exist (and you cannot delete it), you may want to investigate the Supersedes Part/Superseded by Part attributes on the Inventory Part.

Supersedes Part:
The number of the part that has replaced the earlier, if applicable. This information is used when performing deviation analysis and classification job for inventory parts. The superseded part will use the transaction history from the replaced part when performing jobs.

Superseded By Part:
The number of the part that has replaced the earlier, if applicable. This information is used when performing deviation analysis and classification job for inventory parts. The superseded part will not use its own transaction history for subsequent jobs. The transaction history of the superseded part gets inherited by the replacing part instead.

I was not able to find a way to do this globally on the Engineering Part Revision in PDM. Is there a way to do that?