What markings identify an "exchangeable" welding gas cylinder? I'm
shopping casually for a used oxy-acetylene rig and am having
trouble determining what my local Airgas dealer will exchange.

Decades ago I had an O/A rig with owner cylinders, but all my
exchanges were at the same vendor (VB Anderson, if it matters)
so there was never an issue. I don't even remember how or if the
cylinders were marked. Now the nearest major vendor is Airgas and
they're rather unclear about what they will and won't exchange.

I do recall from recent experience with semiconductor gas cylinders
that some are "prepaid demurrage", which isn't refundable and the
cylinders can only be exchanged at the original vendor. Semiconductor
gases are expensive enough that the cylinder does not matter much,
but it'd be an expensive mistake for a welding gas if that practice is used.

Thanks for reading, any counsel appreciated.

bob prohaska

"User Bp" wrote in message
...

What markings identify an "exchangeable" welding gas cylinder? I'm
shopping casually for a used oxy-acetylene rig and am having
trouble determining what my local Airgas dealer will exchange.


https://www.youtube.com/watch?v=ndGB-Ww47M4

Best Regards
Tom.

"User Bp" wrote in message
...

What markings identify an "exchangeable" welding gas cylinder? I'm
shopping casually for a used oxy-acetylene rig and am having
trouble determining what my local Airgas dealer will exchange.

Decades ago I had an O/A rig with owner cylinders, but all my
exchanges were at the same vendor (VB Anderson, if it matters)
so there was never an issue. I don't even remember how or if the
cylinders were marked. Now the nearest major vendor is Airgas and
they're rather unclear about what they will and won't exchange.

I do recall from recent experience with semiconductor gas cylinders
that some are "prepaid demurrage", which isn't refundable and the
cylinders can only be exchanged at the original vendor.
Semiconductor
gases are expensive enough that the cylinder does not matter much,
but it'd be an expensive mistake for a welding gas if that practice
is used.

Thanks for reading, any counsel appreciated.

bob prohaska

The local dealer told me that in general the knee-high 20 cubic foot
cylinders are presumed to be customer-owned and exchangeable unless
you want your own tank refilled, the tall 80 cf ones are presumed to
be rented.

Check the hydro-test date stamp.

Here is TriCo's breakdown:
http://www.tricowelding.com/cylinder_sizing.html

-jsw

The minute you exchange your "owner" cylinder for a gas company
cylinder, you no longer have the owner cylinder. It is a very
unfortunate mess.

I use a lot of oxygen and acetylene (about 5 tanks of oxy and one tank
of acetylene per month). I found a welding gas supplier who is
inexpensive and quite liberal about what cylinders they exchange. I
acquired a lot of tanks at closed down plants and such, they exchanged
them all for Airgas cylinders and they now supply all my welding
gases. I actually have too many tanks and need to sell some.

i

"Ignoramus24975" wrote in
message ...

The minute you exchange your "owner" cylinder for a gas company
cylinder, you no longer have the owner cylinder. It is a very
unfortunate mess.
...
i

But the occasional user can get a cylinder with a later date stamp.
-jsw

"Ignoramus24975" wrote in message
...

The minute you exchange your "owner" cylinder for a gas company
cylinder, you no longer have the owner cylinder. It is a very
unfortunate mess.

I use a lot of oxygen and acetylene (about 5 tanks of oxy and one tank
of acetylene per month). I found a welding gas supplier who is
inexpensive and quite liberal about what cylinders they exchange. I
acquired a lot of tanks at closed down plants and such, they exchanged
them all for Airgas cylinders and they now supply all my welding
gases. I actually have too many tanks and need to sell some.

i

Airgas has been my supplier for over 25 years, never had a problem.
When i moved from chicago to las vegas i took my cylinders with me
and have never been refused a refill. I would be very cautious buying
cylinders from an individual, i see a lot of people trying to sell realy old
(linde,airco,etc) for what you can buy a cylinder from airgas or praxair.

Best Regards
Tom.

Ignoramus24975 wrote:
The minute you exchange your "owner" cylinder for a gas company
cylinder, you no longer have the owner cylinder. It is a very
unfortunate mess.

I use a lot of oxygen and acetylene (about 5 tanks of oxy and one tank
of acetylene per month). I found a welding gas supplier who is
inexpensive and quite liberal about what cylinders they exchange. I
acquired a lot of tanks at closed down plants and such, they exchanged
them all for Airgas cylinders and they now supply all my welding
gases. I actually have too many tanks and need to sell some.

i

Actually , Iggy , when you take that cylinder out the door you own it
every bit as much as the one you left .
To the OP , if the cylinder has a collar that says it's the property of
whatever company , that is usually their cylinder and you'll be charged
rental sometimes called demurrage for it . I've heard cases where someone
buys a used tank , takes it in to swap and is sometimes not so politely
told thanks for returning our tank , now get lost .

--
Snag

On 2015-03-14, Howard Beal wrote:

"Ignoramus24975" wrote in message
...

The minute you exchange your "owner" cylinder for a gas company
cylinder, you no longer have the owner cylinder. It is a very
unfortunate mess.

I use a lot of oxygen and acetylene (about 5 tanks of oxy and one tank
of acetylene per month). I found a welding gas supplier who is
inexpensive and quite liberal about what cylinders they exchange. I
acquired a lot of tanks at closed down plants and such, they exchanged
them all for Airgas cylinders and they now supply all my welding
gases. I actually have too many tanks and need to sell some.

i

Airgas has been my supplier for over 25 years, never had a problem.
When i moved from chicago to las vegas i took my cylinders with me
and have never been refused a refill. I would be very cautious buying
cylinders from an individual, i see a lot of people trying to sell realy old
(linde,airco,etc) for what you can buy a cylinder from airgas or praxair.


My supplier is an airgas dealer, not airgas direct, he takes just
about any cylinder except for Terrace supply etc

I'm starting to appreciate the depth of the mess. It appears that a cylinder
with no engraving on the collar and no hint of a gas distributor name anywhere
in the metal is considered "customer owned". There seems to be some controversy
regarding size. Little cylinders aren't a problem but anything bigger than about
100 cf appears to be questionable.

I'll have to do a little more research before I take the plunge and buy anything,
new or used. In the mid '70s I paid $250 for a Purox set with no tanks. Now I'm
seeing Victor sets with tanks for similar prices. Given inflation, that's a huge
discount. One explanation is that the existing tanks are worthless and new tanks
and gas will be much more expensive in the future. A discouraging trend, indeed!

Thanks to everyody for your guidance!

bob prohaska

"Jim Wilkins" fired this volley in news:me3rv7$9ls
:


They may not want to sell you acetylene unless you can transport it
safely outside the vehicle, like secured upright in the bed of a
pickup.


Yeah... my 'local' NAPA store is the only place closer than 30 miles away
that has gas, and they don't carry every gas in every size of container.

They will readily swap out my tanks, even though I go a year sometimes
before finishing off acetylene. Although he's _remarked_ about the age,
he's never refused to swap.

But he won't let me take a tank unless I have an open truck or my
trailer. I tried once in a cargo van, and he wouldn't allow it to be
loaded. I think he's a smart guy.

LLoyd

On Sun, 15 Mar 2015 07:34:19 -0500, "Lloyd E. Sponenburgh"
lloydspinsidemindspring.com wrote:

"Jim Wilkins" fired this volley in news:me3rv7$9ls
:


They may not want to sell you acetylene unless you can transport it
safely outside the vehicle, like secured upright in the bed of a
pickup.


Yeah... my 'local' NAPA store is the only place closer than 30 miles away
that has gas, and they don't carry every gas in every size of container.

They will readily swap out my tanks, even though I go a year sometimes
before finishing off acetylene. Although he's _remarked_ about the age,
he's never refused to swap.

But he won't let me take a tank unless I have an open truck or my
trailer. I tried once in a cargo van, and he wouldn't allow it to be
loaded. I think he's a smart guy.

Given the potential risk, I can see why.
https://www.youtube.com/watch?v=0fWBINa7cxI
https://www.youtube.com/watch?v=Zt3AV9uO0_Q
https://www.youtube.com/watch?v=UwX5NqhEzbc
https://www.youtube.com/watch?v=S72IbsVoczM

--
However beautiful the strategy, you should occasionally look at the results.
-- Sir Winston Churchill

Lloyd E. Sponenburgh wrote:
"Jim Wilkins" fired this volley in news:me3rv7$9ls
:

They may not want to sell you acetylene unless you can transport it
safely outside the vehicle, like secured upright in the bed of a
pickup.


Yeah... my 'local' NAPA store is the only place closer than 30 miles away
that has gas, and they don't carry every gas in every size of container.

They will readily swap out my tanks, even though I go a year sometimes
before finishing off acetylene. Although he's _remarked_ about the age,
he's never refused to swap.

But he won't let me take a tank unless I have an open truck or my
trailer. I tried once in a cargo van, and he wouldn't allow it to be
loaded. I think he's a smart guy.

LLoyd

I use a hitch mounted carrier to move mine on the back of the Jeep.

--
Steve W.

Larry Jaques wrote:
Given the potential risk, I can see why.
https://www.youtube.com/watch?v=0fWBINa7cxI
https://www.youtube.com/watch?v=Zt3AV9uO0_Q
https://www.youtube.com/watch?v=UwX5NqhEzbc
https://www.youtube.com/watch?v=S72IbsVoczM

I must respectfully disagree. A little soapy water
or a reasonably sensitive nose is enough to forestall
problems. The last video, of the plumber's van, is
the only relevant example and clearly he didn't check
for leaks.

Thanks for the links!

bob prohaska

"User Bp" wrote in message
...
Larry Jaques wrote:
Given the potential risk, I can see why.
https://www.youtube.com/watch?v=0fWBINa7cxI
https://www.youtube.com/watch?v=Zt3AV9uO0_Q
https://www.youtube.com/watch?v=UwX5NqhEzbc
https://www.youtube.com/watch?v=S72IbsVoczM

I must respectfully disagree. A little soapy water
or a reasonably sensitive nose is enough to forestall
problems. The last video, of the plumber's van, is
the only relevant example and clearly he didn't check
for leaks.

Thanks for the links!

bob prohaska

The first set of tanks I bought, back in the 80's, heated up in the
hot car enough to hiss while I was driving them home.

On Sun, 15 Mar 2015 21:59:54 -0400, "Jim Wilkins"
wrote:

"User Bp" wrote in message
...
Larry Jaques wrote:
Given the potential risk, I can see why.
https://www.youtube.com/watch?v=0fWBINa7cxI
https://www.youtube.com/watch?v=Zt3AV9uO0_Q
https://www.youtube.com/watch?v=UwX5NqhEzbc
https://www.youtube.com/watch?v=S72IbsVoczM

I must respectfully disagree. A little soapy water
or a reasonably sensitive nose is enough to forestall
problems. The last video, of the plumber's van, is
the only relevant example and clearly he didn't check
for leaks.

Thanks for the links!

bob prohaska

The first set of tanks I bought, back in the 80's, heated up in the
hot car enough to hiss while I was driving them home.

When I carry tanks in my car, I put them in the trunk with the lid
propped open about a foot and some rope holding the tanks down.

--
Ed Huntress (off to Chicago in a few hours -- see you next Friday)

Here's a good one

https://www.youtube.com/watch?v=S72IbsVoczM

And even better

https://www.youtube.com/watch?v=iam27Mh1zu4

i

On 2015-03-16, User Bp wrote:
Larry Jaques wrote:
Given the potential risk, I can see why.
https://www.youtube.com/watch?v=0fWBINa7cxI
https://www.youtube.com/watch?v=Zt3AV9uO0_Q
https://www.youtube.com/watch?v=UwX5NqhEzbc
https://www.youtube.com/watch?v=S72IbsVoczM

I must respectfully disagree. A little soapy water
or a reasonably sensitive nose is enough to forestall
problems. The last video, of the plumber's van, is
the only relevant example and clearly he didn't check
for leaks.

Thanks for the links!

bob prohaska

On Mon, 16 Mar 2015 01:14:29 +0000 (UTC), User Bp
wrote:

Larry Jaques wrote:
Given the potential risk, I can see why.
https://www.youtube.com/watch?v=0fWBINa7cxI
https://www.youtube.com/watch?v=Zt3AV9uO0_Q
https://www.youtube.com/watch?v=UwX5NqhEzbc
https://www.youtube.com/watch?v=S72IbsVoczM

I must respectfully disagree. A little soapy water
or a reasonably sensitive nose is enough to forestall
problems. The last video, of the plumber's van, is
the only relevant example and clearly he didn't check
for leaks.

It's _because_ people don't check for leaks that DOT made the laws.
I'll bet that plumber got hassled about moving his "dangerous
business" to another neighborhood/city after that.


Thanks for the links!

Jewelcome.

--
However beautiful the strategy, you should occasionally look at the results.
-- Sir Winston Churchill

Jim Wilkins wrote:

The first set of tanks I bought, back in the 80's, heated up in the
hot car enough to hiss while I was driving them home.


Ok, what's the rest of the story?

bob

Larry Jaques wrote:

It's _because_ people don't check for leaks that DOT made the laws.
I'll bet that plumber got hassled about moving his "dangerous
business" to another neighborhood/city after that.


As I understand it, DOT requirements are meant to ensure the tanks are
sound structurally and will fail gracefully (vent) if overstressed. Is
there a clause about end user leak testing? Most folks do it anyway,
either to avoid product loss or prevent product contamination.

It's interesting to note that in the Dallas fire video it appears that the
majority of tanks did fail gracefully by venting. Seemingly only a few blew
up. I suppose that counts as partial success 8-)

An aside, one should remember that an acetylene cylinder contains more
acetone than acetylene. Either one is capable of making mischief. Would
a pile of propane cylinders behave much differently?


bob

On Tue, 17 Mar 2015 01:41:57 +0000 (UTC), User Bp
wrote:

Jim Wilkins wrote:

The first set of tanks I bought, back in the 80's, heated up in the
hot car enough to hiss while I was driving them home.


Ok, what's the rest of the story?

He flicked his Bic to see if he could find where the hiss was coming
from and died right there in a fiery explosion. The next day, he
stopped by the Airgas store and the manager refused to refund his
money for the bottles. "Sorry" he said "we don't serve shades here."

Meanwhile, back at the ranch, little Suzie was making cookies.

--
However beautiful the strategy, you should occasionally look at the results.
-- Sir Winston Churchill

He flicked his Bic to see if he could find where the hiss was coming
from and died right there in a fiery explosion. The next day, he
stopped by the Airgas store and the manager refused to refund his
money for the bottles. "Sorry" he said "we don't serve shades here."

Meanwhile, back at the ranch, little Suzie was making cookies.

--
However beautiful the strategy, you should occasionally look at the results.
-- Sir Winston Churchill

He lit a match.............




To check his tank..............




That's why they call him...........




Skinless Frank.


Burma Shave.

(Seen from the backseat of Dad's '56 Pontiac some time in the early 60's. Somewhere in S. Illinois.

"User Bp" wrote in message
...
Jim Wilkins wrote:

The first set of tanks I bought, back in the 80's, heated up in the
hot car enough to hiss while I was driving them home.


Ok, what's the rest of the story?

bob


I think they overfilled the oxygen. I was startled by a POP and brief
hiss, but didn't smell MAPP gas. I just opened the windows and kept
going.

I vaguely recall the pressure as around 2400 or 2500 PSI after I put
the regulator on the basement-temperature cylinder, and was
disappointed when the next tank was only 1800. The hose they filled
cylinders with didn't have a fragile gauge on the ends, they just left
it connected while they serviced customers, then disconnected it after
'a while'.
http://www.practicalmachinist.com/vb...essure-147852/

"Tanks are normally filled and sold by volume not pressure."
PV = nRT

I mentioned this so you will be prepared when you go to buy them.

-jsw

"Larry Jaques" wrote in message
...
On Tue, 17 Mar 2015 01:41:57 +0000 (UTC), User Bp
wrote:

Jim Wilkins wrote:

The first set of tanks I bought, back in the 80's, heated up in
the
hot car enough to hiss while I was driving them home.


Ok, what's the rest of the story?

He flicked his Bic to see if he could find where the hiss was coming
from and died right there in a fiery explosion. The next day, he
stopped by the Airgas store and the manager refused to refund his
money for the bottles. "Sorry" he said "we don't serve shades
here."

Meanwhile, back at the ranch, little Suzie was making cookies.

I hope you have a good excuse for that, like heavy drinking, rather
than senility.

On 3/17/2015 7:25 AM, Jim Wilkins wrote:
....
"Tanks are normally filled and sold by volume not pressure."
PV = nRT
....

I wonder how they measure volume, if not by pressure! Especially since
cylinders are often/usually filled from a manifold & many cylinders in
parallel. Unless there is a flow gauge on each tank. Doesn't sound
right to me.

Bob

"Bob Engelhardt" wrote in message
...
On 3/17/2015 7:25 AM, Jim Wilkins wrote:
...
"Tanks are normally filled and sold by volume not pressure."
PV = nRT
...

I wonder how they measure volume, if not by pressure! Especially
since cylinders are often/usually filled from a manifold & many
cylinders in parallel. Unless there is a flow gauge on each tank.
Doesn't sound right to me.

Bob

Cylinder gas is sold by the volume when expanded at atmospheric
pressure.
http://www.alspecialtygases.com/volu..._cylinder.aspx

You can calculate the amount you actually received if you know the
pressure, temperature and 'water' volume of the cylinder, or like
packaged food you can just trust them.

-jsw

On Tuesday, March 17, 2015 at 7:42:43 AM UTC-4, Jim Wilkins wrote:
"Larry Jaques" wrote in message
...
On Tue, 17 Mar 2015 01:41:57 +0000 (UTC), User Bp
wrote:

Jim Wilkins wrote:

The first set of tanks I bought, back in the 80's, heated up in
the
hot car enough to hiss while I was driving them home.

Ok, what's the rest of the story?

He flicked his Bic to see if he could find where the hiss was coming
from and died right there in a fiery explosion. The next day, he
stopped by the Airgas store and the manager refused to refund his
money for the bottles. "Sorry" he said "we don't serve shades
here."

Meanwhile, back at the ranch, little Suzie was making
cookies.

I hope you have a good excuse for that, like heavy drinking,
rather than senility.

Probably both. 24 hours too, I bet.

On 3/17/2015 12:47 PM, Jim Wilkins wrote:
"Bob Engelhardt" wrote in message
...
On 3/17/2015 7:25 AM, Jim Wilkins wrote:
...
"Tanks are normally filled and sold by volume not pressure."
PV = nRT
...

I wonder how they measure volume, if not by pressure! Especially
since cylinders are often/usually filled from a manifold & many
cylinders in parallel. Unless there is a flow gauge on each tank.
Doesn't sound right to me.

Bob

Cylinder gas is sold by the volume when expanded at atmospheric
pressure.
http://www.alspecialtygases.com/volu..._cylinder.aspx

You can calculate the amount you actually received if you know the
pressure, temperature and 'water' volume of the cylinder, or like
packaged food you can just trust them.

-jsw


Right, I know. That's why I wondered when your quote from the
practicalmachinist said: "Tanks are normally filled and sold by volume
not pressure." I'll repeat: how do they measure it if NOT by pressure?

Bob

On Tue, 17 Mar 2015 18:44:46 -0400, Bob Engelhardt
wrote:

On 3/17/2015 12:47 PM, Jim Wilkins wrote:
"Bob Engelhardt" wrote in message
...
On 3/17/2015 7:25 AM, Jim Wilkins wrote:
...
"Tanks are normally filled and sold by volume not pressure."
PV = nRT
...

I wonder how they measure volume, if not by pressure! Especially
since cylinders are often/usually filled from a manifold & many
cylinders in parallel. Unless there is a flow gauge on each tank.
Doesn't sound right to me.

Bob

Cylinder gas is sold by the volume when expanded at atmospheric
pressure.
http://www.alspecialtygases.com/volu..._cylinder.aspx

You can calculate the amount you actually received if you know the
pressure, temperature and 'water' volume of the cylinder, or like
packaged food you can just trust them.

-jsw


Right, I know. That's why I wondered when your quote from the
practicalmachinist said: "Tanks are normally filled and sold by volume
not pressure." I'll repeat: how do they measure it if NOT by pressure?

Bob
I'm pretty sure they measure temperature and pressure to arrive at the
volume of gas in the cylinder. But since the temperature may be
different when you pick up the cylinder the pressure will vary. So on
a cold day there is less pressure, a hot day more pressure, but the
same volume of gas in all cylinders. Acetylene cylinders show a very
wide pressure swing with changing temperature. That's why it is hard
to know how much gas is really left in the acetylene cylinder unless
you know both temp and pressure.
Eric

Bob Engelhardt fired this volley in
:

I'll repeat: how do they measure it if NOT by pressure?

Bob... pressure AND temperature.

A bit of simple algebra does it for the one-timer, but they have tables of
the pressure they need to make at a given ambient temperature and filling
time (and thus, the presumed heating of the contents during pump-up) to
make the STP volume.

Lloyd

"Bob Engelhardt" wrote in message
...
On 3/17/2015 12:47 PM, Jim Wilkins wrote:
"Bob Engelhardt" wrote in message
...
On 3/17/2015 7:25 AM, Jim Wilkins wrote:
...
"Tanks are normally filled and sold by volume not pressure."
PV = nRT
...

I wonder how they measure volume, if not by pressure! Especially
since cylinders are often/usually filled from a manifold & many
cylinders in parallel. Unless there is a flow gauge on each tank.
Doesn't sound right to me.

Bob

Cylinder gas is sold by the volume when expanded at atmospheric
pressure.
http://www.alspecialtygases.com/volu..._cylinder.aspx

You can calculate the amount you actually received if you know the
pressure, temperature and 'water' volume of the cylinder, or like
packaged food you can just trust them.

-jsw


Right, I know. That's why I wondered when your quote from the
practicalmachinist said: "Tanks are normally filled and sold by
volume not pressure." I'll repeat: how do they measure it if NOT by
pressure?

Bob

I put the Ideal Gas Law equation, without comment, under that quote to
see if anyone caught on that I disagree with it.

Yeah, it was Sheldon/Amy humor.

-jsw

wrote in message
...
On Tue, 17 Mar 2015 18:44:46 -0400, Bob Engelhardt
wrote:

I'm pretty sure they measure temperature and pressure to arrive at
the
volume of gas in the cylinder. But since the temperature may be
different when you pick up the cylinder the pressure will vary. So
on
a cold day there is less pressure, a hot day more pressure, but the
same volume of gas in all cylinders. Acetylene cylinders show a very
wide pressure swing with changing temperature. That's why it is hard
to know how much gas is really left in the acetylene cylinder unless
you know both temp and pressure.
Eric

The little I've seen suggests they hook the cylinder to a hose from
the manifold and just leave it for a while, hopefully long enough for
it to fill and cool to loading dock temperature. It's hard enough to
get a good answer on welding from them, I won't even try physics or
chemistry.

-jsw

On Tue, 17 Mar 2015 00:58:51 -0700 (PDT), Garrett Fulton
wrote:


He flicked his Bic to see if he could find where the hiss was coming
from and died right there in a fiery explosion. The next day, he
stopped by the Airgas store and the manager refused to refund his
money for the bottles. "Sorry" he said "we don't serve shades here."

Meanwhile, back at the ranch, little Suzie was making cookies.

He lit a match.............

To check his tank..............

That's why they call him...........

Skinless Frank.

Burma Shave.

Loved 'em.


(Seen from the backseat of Dad's '56 Pontiac some time in the early 60's. Somewhere in S. Illinois.

Kinda like this guy with a tanker truck?
https://www.youtube.com/watch?v=-5M--0CSZ1I

--
However beautiful the strategy, you should occasionally look at the results.
-- Sir Winston Churchill

On Tue, 17 Mar 2015 07:43:22 -0400, "Jim Wilkins"
wrote:

"Larry Jaques" wrote in message
.. .
On Tue, 17 Mar 2015 01:41:57 +0000 (UTC), User Bp
wrote:

Jim Wilkins wrote:

The first set of tanks I bought, back in the 80's, heated up in
the
hot car enough to hiss while I was driving them home.


Ok, what's the rest of the story?

He flicked his Bic to see if he could find where the hiss was coming
from and died right there in a fiery explosion. The next day, he
stopped by the Airgas store and the manager refused to refund his
money for the bottles. "Sorry" he said "we don't serve shades
here."

Meanwhile, back at the ranch, little Suzie was making cookies.

I hope you have a good excuse for that, like heavy drinking, rather
than senility.

I don't drink, so it can only be attributed to a creative streak.
takes bow

--
However beautiful the strategy, you should occasionally look at the results.
-- Sir Winston Churchill

On Tuesday, March 17, 2015 at 9:48:48 PM UTC-4, Larry Jaques wrote:
On Tue, 17 Mar 2015 00:58:51 -0700 (PDT), Garrett Fulton
wrote:


He flicked his Bic to see if he could find where the hiss was coming
from and died right there in a fiery explosion. The next day, he
stopped by the Airgas store and the manager refused to refund his
money for the bottles. "Sorry" he said "we don't serve shades here."

Meanwhile, back at the ranch, little Suzie was making cookies.

He lit a match.............

To check his tank..............

That's why they call him...........

Skinless Frank.

Burma Shave.

Loved 'em.


(Seen from the backseat of Dad's '56 Pontiac some time in the early 60's. Somewhere in S. Illinois.

Kinda like this guy with a tanker truck?
https://www.youtube.com/watch?v=-5M--0CSZ1I

--
However beautiful the strategy, you should occasionally look at the results.
-- Sir Winston Churchill

Wow. So many people with good sense unemployed. And that guy's got a job. Well....maybe not now.

On 2015-03-17, wrote:
On Tue, 17 Mar 2015 18:44:46 -0400, Bob Engelhardt
wrote:

On 3/17/2015 12:47 PM, Jim Wilkins wrote:
"Bob Engelhardt" wrote in message
...
On 3/17/2015 7:25 AM, Jim Wilkins wrote:
...
"Tanks are normally filled and sold by volume not pressure."
PV = nRT
...

I wonder how they measure volume, if not by pressure! Especially
since cylinders are often/usually filled from a manifold & many
cylinders in parallel. Unless there is a flow gauge on each tank.
Doesn't sound right to me.

[ ... ]

I'm pretty sure they measure temperature and pressure to arrive at the
volume of gas in the cylinder. But since the temperature may be
different when you pick up the cylinder the pressure will vary. So on
a cold day there is less pressure, a hot day more pressure, but the
same volume of gas in all cylinders. Acetylene cylinders show a very
wide pressure swing with changing temperature. That's why it is hard
to know how much gas is really left in the acetylene cylinder unless
you know both temp and pressure.
Eric

What about by weight -- if there is a tare weight stamped on the
cylinder. Not sure how that would work with acetylene howeer, with all
that liquid acetone in there.

Enjoy,
DoN.

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