Gas cylinder hrdrotest question

reggie_obe · Nov 19, 2021

Searched, but I can't find an answer.
I have several 20 cu. ft. high pressure cylinder I bought used, some still some O2 left in them others are empty. They all have a manufacture date of 2014, 2016, etc., but none of them have a hydro re-test stamp. They were purchased new, filled, used and then the company went out of business. Do new cylinders automatically fall under the 10 year hydro test rule or the 5 year hydro? Should I be looking for a star after date of manufacture.

DDoug · Nov 19, 2021

reggie_obe said:
Searched, but I can't find an answer.
I have several 20 cu. ft. high pressure cylinder I bought used, some still some O2 left in them others are empty. They all have a manufacture date of 2014, 2016, etc., but none of them have a hydro re-test stamp. They were purchased new, filled, used and then the company went out of business. Do new cylinders automatically fall under the 10 year hydro test rule or the 5 year hydro? Should I be looking for a star after date of manufacture.

Whom is going to be filling them ?

reggie_obe · Nov 19, 2021

digger doug said:
Whom is going to be filling them ?

Don't see that as relevant, but will be filled by my local industrial gasses dealer.
My concern is them applying an un-necessary hydrotest charge because of my lack of knowledge.

DDoug · Nov 19, 2021

reggie_obe said:
Don't see that as relevant, but will be filled by my local industrial gasses dealer.
My concern is them applying an un-necessary hydrotest charge because of my lack of knowledge.

You ask them.
some only need the 10 yr, others make it 5yrs for "customer owned" bottles.

That makes it relevent, very much so.

Strostkovy · Nov 19, 2021

reggie_obe said:
Don't see that as relevant, but will be filled by my local industrial gasses dealer.
My concern is them applying an un-necessary hydrotest charge because of my lack of knowledge.

I'd call and ask about their policy without telling them anything about the bottle.

jermfab · Nov 19, 2021

I’m completely unaware of a five-year rule for anything other than aluminum dive-tanks.

As has been said, your local welding has supplier is the only person who’s opinion matters.

That said, the gas outfit I typically use waives the test so long as the bottle comes in with SOME pressure in it.

Be safe

Jeremy

LKeithR · Nov 19, 2021

jermfab said:
...That said, the gas outfit I typically use waives the test so long as the bottle comes in with SOME pressure in it....

I think you're confusing a hydro-test with a test for contamination.

Typical high pressure gas bottle require a hydro-test every 10 years for safety reasons. I can't see a
gas supplier "waiving" that test for any reason. It's probably a DOT thing too, I suspect that transporting
out of test bottles gets their attention. Worker's comp agencies are also interested in the status of
your bottles--they have been know to check bottles for compliance when doing inspections.

On the other hand empty bottles being returned for filling with zero or very low pressure need to be
purged before filling to ensure that there is no contaminating air in the tank. Anyone who has been
welding for very long has occasionally gotten a bottle of "skunky" gas from their suppliers. It happens
because whoever was filling the bottle didn't check or because they thought there was enough residual
pressure to ensure that there was no contamination. That's why you should always leave a bit of
pressure in a tank when you're done with it....

Strostkovy · Nov 19, 2021

LKeithR said:
I think you're confusing a hydro-test with a test for contamination.

Typical high pressure gas bottle require a hydro-test every 10 years for safety reasons. I can't see a
gas supplier "waiving" that test for any reason. It's probably a DOT thing too, I suspect that transporting
out of test bottles gets their attention. Worker's comp agencies are also interested in the status of
your bottles--they have been know to check bottles for compliance when doing inspections.

On the other hand empty bottles being returned for filling with zero or very low pressure need to be
purged before filling to ensure that there is no contaminating air in the tank. Anyone who has been
welding for very long has occasionally gotten a bottle of "skunky" gas from their suppliers. It happens
because whoever was filling the bottle didn't check or because they thought there was enough residual
pressure to ensure that there was no contamination. That's why you should always leave a bit of
pressure in a tank when you're done with it....

We checked with our welding supplier, and they pump down all bottles before refilling.

dana gear · Nov 24, 2021

Your cylinders are customer owned cylinders. The reason for no retest date is that the cylinders were tested when manufactured and then sold, and used during there PRE 5-year hydro cycle.
So if your manufacture dates are correct then the cylinders would need to be tested before a refill.
Steel cylinders generally need to be Hyro-tested every 5 years.
If there is a "star" stamped into the top of the cylinder by the neck ring then the cylinder has met the standards to allow for a every 10-year hydro-test.
If there is a + {plus} stamped into the top of the cylinder by the neck ring then it is safe to fill 10 percent over the stamped rated pressure.

jermfab · Nov 26, 2021

LKeithR said:
I think you're confusing a hydro-test with a test for contamination.

Typical high pressure gas bottle require a hydro-test every 10 years for safety reasons. I can't see a
gas supplier "waiving" that test for any reason.

It’s quite possible I didn’t interpret what the guy was telling me correctly…

As an aside, the tank in question had an “U.S. Army Air Corp” band on it. And nowhere near the required number of hydrostatic test dates below.

I took note because of the unique and way obsolete tag on the tank. My words were something like: “we haven’t had one of THOSE in quite some time”. The Army Air Corp band caused me to look closer and I also noted that the most recent cert was outside of the ten-year window. Sometime in the 80’s, if memory serves.

That’s when the guy mentioned *something* about the tank must’ve kept pressure on it.

Around here the best and brightest are typically only customers at the welding shop and the shop definitely doesn’t put THEIR best and brightest on the road delivering tanks…

Plenty of places to lose something in translation.

Be safe

Jeremy

reggie_obe · Nov 27, 2021

dana gear said:
Your cylinders are customer owned cylinders. The reason for no retest date is that the cylinders were tested when manufactured and then sold, and used during there PRE 5-year hydro cycle.
So if your manufacture dates are correct then the cylinders would need to be tested before a refill.
Steel cylinders generally need to be Hyro-tested every 5 years.
If there is a "star" stamped into the top of the cylinder by the neck ring then the cylinder has met the standards to allow for a every 10-year hydro-test.
If there is a + {plus} stamped into the top of the cylinder by the neck ring then it is safe to fill 10 percent over the stamped rated pressure.

Thanks. Clear and concise reply that relates to my tanks.

johfoster · Nov 27, 2021

I think the last tank I brought in that was due for testing the charge was still under $10 for the test. I wouldn't lose too much sleep about it. I don't think our gas supplier usually checks them on exchange to be honest. When the bill is a few hundred dollars they might not care to charge for it, idk.

dana gear · Nov 27, 2021

Ya, generally about 12 bucks to hydro, although some fillers charge 25 bucks or more in some cases.
Steel cylinders are amazing, I have seen High pressure cylinders that had {INT] build dates of the mid 1920's, that still hydro and are good to go again. There still tons of WW2 cylinders around.
I have been in this business for ever and have never seen a fill station refill a HP cylinder out of hydro.
(Past hydro retest date) It could be dangerous and it's illegal.

Search

Largest Manufacturing Technology Community on the Web

Search

Gas cylinder hrdrotest question

reggie_obe

Diamond

DDoug

Diamond

reggie_obe

Diamond

DDoug

Diamond

Strostkovy

Titanium

jermfab

Cast Iron

LKeithR

Stainless

Strostkovy

Titanium

dana gear

Hot Rolled

jermfab

Cast Iron

reggie_obe

Diamond

johfoster

Cast Iron

dana gear

Hot Rolled

Similar threads