Steel Tank Condemned: Cracks in Threads?

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Regarding penetrant indicators contaminating the defect - wouldn't that only happen if indeed the defect is a crack and not just a surface mark, in which case the the tank is garbage anyway?
You can still get contamination in the threads, depending on how they are cut. They're bound to have small laps and burrs. Not a huge problem IF you're aware and then able to subject the tanks to a very good clean, which might be outside the abilities of those testing.

In this case penetrant test is of not point since you can already see the defect, you'd want to try something else in order to establish whether crack or mechanical defect.

Often penetrant is simply used as go/ no go, with suspect items being sent for further evaluation
 
Got to check it out today. It looks pretty sketchy. The crack or whatever it is does extend below the threads.

I just left it at the shop. They’ve got a PSI instructor dropping by early next year, so I’ll let him check it out and see what he thinks of it. Unless he’s like “that’s a pretty common example of a Monday morning or Friday afternoon tank from Asahi...there’s nothing to worry about,” I’m going to just let them condemn it.
 
Got to check it out today. It looks pretty sketchy. The crack or whatever it is does extend below the threads.

I just left it at the shop. They’ve got a PSI instructor dropping by early next year, so I’ll let him check it out and see what he thinks of it. Unless he’s like “that’s a pretty common example of a Monday morning or Friday afternoon tank from Asahi...there’s nothing to worry about,” I’m going to just let them condemn it.
Any pictures?
Did this cylinder go to the great gas cloud in the sky?
 
It’s been a while, but I wanted to follow-up on this (I heard back a couple weeks ago, but I’ve been busy). Word from the PSI instructor is that they’re tool marks...not a crack.

It’ll get put back into service soon and I’m guessing that I’ll get to deal with this each time I take it in for inspection.
 
no you wont ....just take it too someone whos competent
 
It’s been a while, but I wanted to follow-up on this (I heard back a couple weeks ago, but I’ve been busy). Word from the PSI instructor is that they’re tool marks...not a crack.

It’ll get put back into service soon and I’m guessing that I’ll get to deal with this each time I take it in for inspection.
Thanks for letting us know the outcome of this.

Next VIP bring it to the same shop and bring the pictures you have so they can compare with the next inspection. Even if there is a new inspector at the shop, he should have access to the shops old inspection sheet for that tank which should mention the marks seen as machine marks.
 
It’s been a while, but I wanted to follow-up on this (I heard back a couple weeks ago, but I’ve been busy). Word from the PSI instructor is that they’re tool marks...not a crack.

It’ll get put back into service soon and I’m guessing that I’ll get to deal with this each time I take it in for inspection.
I'm glad you had PSI look at it.
And I'm glad I took their course, for all the bad mouthing they get. The pic was pretty classic for a tool stop.
I believe those are stop marks from the threading bit.
No. I'm not patting myself on the back as much as saying that sometimes it's worth it to pay the money and take the course.
 

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