Is there a hydro requirement on bank cylinders?

[Wookie]

Provide a link to validate your assumptions.

Seeing is believing.


Buddhist monks have endowed me with the power of observation, power of thought, power of suggestion.

Four Cylinder Filling Tips - GAWDA Media

 

[Scuba Client]

Four Cylinder Filling Tips - GAWDA Media

(Note that a hammer test is not effective on aluminum cylinders.)
I specifically talking about smashing indents into the crown as part of the hydro which Luxfer tank manufacturer describes as negligent. Your reference is just some unsubstantiated internet troll. Produce DOT Act for immediate verification.

 

[The Ruttmeister]

Interpretation Response | PHMSA

Oh, I dunno, if you dispute someones position, you could do like, 1 Google search and read a DOT letter discussing when the hammer test is applicable.
I suggest you go read all the relevant regs they cite if you want to dispute it.

 

[Michael Perdue]

Every hydro will last a life time... which might not be as long as you hoped.

 

[flymolo]

I never heard of the hammer test, although now that I have it sounds like something I might want to do from time to time with my 3L oxygen cylinders. I've never managed to empty one completely on a dive nor do I hope to, but I'm always paranoid about water in a cylinder after I found some in an AL6 inflation bottle after I emptied it on a dive. Thanks for the useful info @Wookie .

 

[tbone1004]

I never heard of the hammer test, although now that I have it sounds like something I might want to do from time to time with my 3L oxygen cylinders. I've never managed to empty one completely on a dive nor do I hope to, but I'm always paranoid about water in a cylinder after I found some in an AL6 inflation bottle after I emptied it on a dive. Thanks for the useful info @Wookie .

they don't have to be empty to do it. It's similar to the hammer test used on train wheels. If it doesn't ring, there is a crack somewhere, guaranteed. If it does ring, it's probably fine structurally. Doesn't have to be a hard hit, you can do it with a bolt snap

 

[Wookie]

they don't have to be empty to do it. It's similar to the hammer test used on train wheels. If it doesn't ring, there is a crack somewhere, guaranteed. If it does ring, it's probably fine structurally. Doesn't have to be a hard hit, you can do it with a bolt snap

And in the marine engineering business, it’s called a ring check. You don’t want to untorque and retorque engine foundation bolts, especially for 100,000 horsepower turbines. Instead you hit them with a hammer, and if they thud, you need to torque them. If they ring, they are considered still torqued.

 

[broncobowsher]

The ring check is also used for grinding wheels to check for cracks before you bring them up to speed.
Almost the same can be used to tell if a tank is filled. Lift a tank about 4" above the floor (good solid concrete floor) and drop vertically. You will get a ring. Works even on aluminum. The more pressure in the tank, the higher the pitch of the ring. Comes in handy when filling a bunch of tanks and you are sorting out the half fulls from the nearly emptys.

I saw a reference above stating that OSHA requirement for DOT standards. Could you provide a link to back that up? It's nice to spread myths, better to spread facts. So far that is the only one that looks to have any impact to what this thread started life as. requirements for non-mobile banked cylinders. No arguing that hydro is a good practice, but have not established that it is in fact required.

For most of the industrial cylinders this is a non-issue. You use the gas provided, return the empty, gas supplier verifies the hydro is good before refilling. Since each fill sends the cylinder out for transport, DOT standards cover the inspection. Scuba tanks are the same way, they go out the door for transport and fall under DOT guidelines. But non-transported tanks are not under DOT guidelines. OSHA, sure. OSHA says they have to be chained up. But where is the CFR for inspection?

Good practice does not mean that is the requirement. Just because you, your shop. or your school does it, doesn't mean it is required to be done that way. Good practice, yes. But still not seen any evidence that it is actually a requirement of non-transported tanks.

 

[rjack321]

But where is the CFR for inspection?

Good practice does not mean that is the requirement. Just because you, your shop. or your school does it, doesn't mean it is required to be done that way. Good practice, yes. But still not seen any evidence that it is actually a requirement of non-transported tanks.

Unless your shop extends over state lines there won't be one for stationary cylinders. Congress only has authority (via DOT) to regulate interstate commerce and the DOT packaging & testing specifications were written to that end.

Your state laws may cite DOT or CGA or ASTM requirements for stationary or "all" cylinders though.

 

[akdeepdiver]

Provide a link to validate your assumptions.

Seeing is believing.


Buddhist monks have endowed me with the power of observation, power of thought, power of suggestion.

-49 CFR Part 180.29(b)(iii)
-CGA Pam C-6 IBR 49 CFR 171.7