O2 cylinder

In my professional capacity as a nondestructive test engineer, I was
peripherally involved in the successful effort to get DOT approval for
acoustic testing of high pressure cylinders carrying gasses on truck
trailers, as well as for acoustically testing composite liquefied
natural gas cylinders used in automobiles. I have also personally used
acoustics to inspect pressure systems used in Mach 14 wind tunnels that
involve pressures up to 60,000 (yes, sixty thousand) psi of air. Those
were some crazy thick walled pressure vessels...made the 16 inch rifles
on the battleship New Jersey look puny!

In the United States pressure vessels must be certified to either DOT
or ASME standards. If a pressure vessel to be used in the USA does not
have either DOT or ASME certification, it is illegal to use it, much
less to fill it. For example, check out Michelin, Continental,
Bridgestone, Dunlop or Pirelli tires - they all have a DOT approval for
USA usage, even though they aren't made here. Yes, tires are considered
to be a pressure vessel - so is your hot water heater, for that
matter.

Sorry, Hartley, you're going to have to buy another oxygen cylinder
if you want to be legal.

-John

jcarlyle wrote:
In my professional capacity as a nondestructive test engineer, I was
peripherally involved in the successful effort to get DOT approval for
acoustic testing of high pressure cylinders carrying gasses on truck
trailers, as well as for acoustically testing composite liquefied
natural gas cylinders used in automobiles. I have also personally used
acoustics to inspect pressure systems used in Mach 14 wind tunnels that
involve pressures up to 60,000 (yes, sixty thousand) psi of air. Those
were some crazy thick walled pressure vessels...made the 16 inch rifles
on the battleship New Jersey look puny!

In the United States pressure vessels must be certified to either DOT
or ASME standards. If a pressure vessel to be used in the USA does not
have either DOT or ASME certification, it is illegal to use it, much
less to fill it. For example, check out Michelin, Continental,
Bridgestone, Dunlop or Pirelli tires - they all have a DOT approval for
USA usage, even though they aren't made here. Yes, tires are considered
to be a pressure vessel - so is your hot water heater, for that
matter.

Bicycle tires and rims too (never heard this)? *Much* higher pressure
than car tires.

Shawn

On 5 Feb 2006 14:18:32 -0800, "jcarlyle" wrote:

In the United States pressure vessels must be certified to either DOT
or ASME standards. If a pressure vessel to be used in the USA does not
have either DOT or ASME certification, it is illegal to use it, much
less to fill it.

John, can you provide support for that? I'm in the hydraulics
industry, and we have charged (and recharged) accumulators and gas
bottles for years that are neither DOT nor ASME approved. These are
not always old, nor small ... I worked with one gas bottle pressurized
to 3800 psi by N2 which cycles between 4200 and 4800 every 50 seconds
.... with a volume of over 200 gallons. I just commissioned a system
with 2 new (2005 manufacture) 32 liter accumulators that were bought
by others from others, but to which I pressurized. I "trusted" the
ratings stamped on the shell, but they had no approval stamps
(manufacturer offers ASME or TUV as options; neither engineer nor user
requested it). Am _I_ breaking the law?

We constantly wonder when pneumatic cylinders are going to be
considered pressure vessels in the USA; the PED (Pressure Equipment
Directive) of the EU already has criteria.