Mike S. said:
If I understand Jay's concern, there may not be an identifiable root cause for this happening, but I don't of course understand the process.
Has it ever happened before? How often?
Either the machine will in fact allow an unwelded part to move or else there is another route.
But I agree with the concept that there are times when an 8-D or formal CA is not appropriate except perhaps to say "no action taken".
For my two cents (which is not much, compared to the Euro) - Jay's company is on the hook for the
8D [or some CA.] (Sometimes the solution may be so obvious, a full-blown 8D is not necessary.)
The question of who "ratted him out" to the customer is moot. Most automotive contracts from OEMs have been including a clause that everyone in the supply chain is supposed to report to the OEM any nonconformances which resulted in internal Corrective Action. The subsequent links in the supply chain were eager to buck the problem to someone else.
If I were in charge at Jay's company. I'd pull out all stops to find the root cause, even if it is one-time sabotage.
One thing I'd be darn sure of is that I got the suspect part to do an intensive examination to ensure:
- it was indeed MY part (Often we only were a partial supplier of an identical part to an OEM and over the course of years, some nonconforming parts were misidentified as ours. We demonstrated by machine tool "signatures" they were NOT ours.)
- whether there had EVER been a weld (could the nuts have been poorly welded and knocked off in subsequent handling?)
- if there had NEVER been a weld, were there any handling or tooling marks to show it had gone through the "motions" of our welding process or was it a stray blank that may have been tossed into a finished bin by human intervention?
Without the suspect piece part for examination, the 8D process really doesn't begin to solve the situation. I'm thinking particularly of steps three and four in the Eight Discipline process:
3. Implement and Verify Short-Term Corrective Actions
Define and implement those intermediate actions that will protect the customer from the problem until permanent corrective action is implemented. Verify with data the effectiveness of these actions.
4. Define and Verify Root Causes
Identify all potential causes which could explain why the problem occurred. Test each potential cause against the problem description and data. Identify alternative corrective actions to eliminate root cause.
Ultimately, as described, the situation doesn't affect the end customer at all, especially if one of the next two links in the supply chain is making an assembly using one or both of the welded nuts. Without the nut, the assembly can't proceed. Perhaps the subsequent links in the supply chain could also adopt the Poka Yoke concept to use the nuts for foolproof locating of the piece part prior to performing the subsequent process.