they usually are but cracks propagate from the inside of the tank out, so the absence of any cracking on the hills of the threads is diagnostic of tool marks, which are most common in steel tanksThe machine marks look straighter
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they usually are but cracks propagate from the inside of the tank out, so the absence of any cracking on the hills of the threads is diagnostic of tool marks, which are most common in steel tanksThe machine marks look straighter
It is HIGHLY unlikely that there was actually a crack in the threads...
What about taking it directly to a hydro facility?
I had looked at Eddy current looks like, per wiki, they use it for different steels.
Could you xray? It would show the fault in the material but at what cost?
If this were a submarine part it would be X-rayed and either wet magnetic particle checked or liquid penetrant checked. The X-ray would readily detect a deep crack, liquid MP would detect a surface crack. Being steel the florescent mag particle testing and X-ray is what Electric Boat would use.
Possibly have Eddy current done?
I'll defend the inspector as making a good call. If in doubt err on the side of caution
Same
I happen to think these are tool marks, but their jagged nature is still worrisome and there is no shame in condemning this tank.