Argon Cylinder Testing ,,Age limit??

I got nailed with this a couple years ago. Liquid Aire (my cylinder) was renamed Aire Liquid thus they would not refill my cylinder.

What got me they didn't even hide the fact with just switching the name around.

I ended up buying a new cylinder, $165 full AR, 220cft.

Gees that burnt me but there was nothing I could do as I made a few calls.

T_Bone

A gas cylinder has a life cycle of about 20,000 fills (from 0/psi to its rated pressure (2015 psi/2265 psi depending on its use) If the cylinder has no obvious damage to the body or neck ring; a hydro test should be all you need. Do not let them discard your cylinder.

You can read the actual regulations many different places, but one web search turns up this site:

Link

The type of cylinder should be stamped into the body, somewhere near the neck. I expect you would have a DOT-3A or DOT-3AA cylinder. This is a medium wall steel cylinder rated for about 2000 PSI. Hydrostatic testing is reqired every 5 years, but this can be extended to 10 years if the cylinder is used for (amoung other things) argon, and is removed from the vehicle or rack each time it is refilled. The date of the last hydro test should be stamped into the top of the cylinder.

I don't believe there is any life limit on a DOT-3A cylinder used for argon, so long as it passes visual inspection. The cylinder can remain in service beyond its next required inspection, but before it can be refilled, it must have a current inspection.

Hydrostatic testing is not particularly expensive -- a typical MIG welder sized tank should cost about $25.00 to get inspected and stamped with a fresh date. You can find a hydro place by looking under "fire extinguishers" in the Yellow pages. Call a few, and ask them where to get your tank tested. Drop the tank off, come back in an hour, pay the $25.00, and you should be good to go for another 10 years.

Around here, you buy the first cylinder from the local welding gas company, and then exchange it for a (different) filled cylinder when you use up the contents. The supplier doesn't even check the hydro date on the cylinder you turn in, just rolls the cylinder over to the "outgoing cylinders to be refilled" area. There is always some risk of the "hot potato" effect -- getting stuck with an out of hydro cylinder -- so I always check the date on the replacement cylinder. But the local supplier just seems to eat the required inspections -- judging from their seeming indifference to the date on the turned in cylinder.