There is much discussion and confusion regarding the difference between rework and repair in a manufacturing environment. This is due to so many industry specifications.
These specifications are rarely written in simple English and are full of jargon and legalese.
I’ve Googled this subject and found an enormous array of answers. From my experience the difference between rework v repairs is much simpler than anything I’ve read online. Naturally you must research your particular situation when in doubt simply ask auditors.
Let me share my simple definition of rework v repair.
Rework – Bringing a non-conforming part back into conformance by simply reprocessing a prior sequence.
Repair – Bringing a non-conforming part back into conformance using methods outside the original process.
10. Pull widget blank from stock.
15. Drill .015 – .020 diameter lock ring hole using G9746 press.
25. In process inspect
30. Heat Treat (Harden)
35. Final Inspect
Let’s review two scenarios of non-conformance.
Drilled hole found to be .005 undersized at sequence 25 the in process inspection. Engineer determined worn or wrong size drill was the root cause. The rework simply involves changing drill bit and reprocessing sequence 15 and continue router from that point.
This is considered rework because you simply redoing a process correctly.
Drilled hole found to be .005 undersized at sequence 35 final inspection. Engineer again determined worn or wrong size drill was the root cause. However this time the part was found in a hardened state. Engineer must repair by adding sequence not on the original router.
Before reprocessing sequence 25 the Engineer must soften material using the thermal process called annealing.
Because there was a new process introduced it would be considered a repair.
This simple explanation will fit the machining process the best. Each industry and situation has its own nuanced definition of rework v repair so be sure to know yours. Use my definition as a talking point to begin the conversation.
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