On Monday, December 20, 1999 3:00:00 AM UTC-5, Craig C. wrote:
(Mike14k) wrote:

I have "inherited" an aluminum tank labled "Breathing Oxygen" from a WW II
airplane. It is roughly 24" long, 15" in diameter and rounded on the ends with
a carrying handle. Inlet/outlet on each end...... Handle on top.

They were used in low pressure O2 systems....working pressure of
400-500psi. The tank that you have is a portable from one of the
bigger bombers. It is probably worth more as a WW2 a/c part to you
than as an air tank.

At the museum that I used to work for, we used the O2 tanks from our
B-36 as air tanks while we were working on all the other a/c. Had them
in the bed of a 5 ton truck and the air system off the truck plumbed
to the tanks and then regulators on the hose manifold.

Craig

I have a yellow WWII aluminum tank like you describe. My pop used it from 1940's until he passed away in 2001. I inherited it and used it since. I just bought a new Porter Cable compressor that pumps up to 150 psi. That is about 25 psi higher than dad or I either one ever used before so I was logging in to see if the rating 200 psi or so.

Dad later used a hot water tank for years and that was a real big improvement for volume. I too agree recycling is fine and do not believe that there is any issue as long as one uses equipment within design perimeters.

I far prefer a USA made WWII aluminum tank to an new steel one from China any day of the week. Let's see how many Chinese tanks made from old car bumpers are still around in 70 years like my WWII Oxygen tank. So the fellow below alarmed at this thought can take his new Chinese tank and I'll use my USA WWII bomber tank and we will both be happy.

Just be sure to install a pressure relief valve as someone stated below (always do that on any tank) so if there is a fire, the tank does not explode. The relief valve must be connected such that there is never a valve between the tank and the relief valve.

Best of luck.

On Wed, 12 Feb 2014 15:49:00 -0800 (PST), wrote:

I have a yellow WWII aluminum tank like you describe. My pop used it from 1940's until he passed away in 2001. I inherited it and used it since. I just bought a new Porter Cable compressor that pumps up to 150 psi. That is about 25 psi higher than dad or I either one ever used before so I was logging in to see if the rating 200 psi or so.

Dad later used a hot water tank for years and that was a real big improvement for volume. I too agree recycling is fine and do not believe that there is any issue as long as one uses equipment within design perimeters.

I far prefer a USA made WWII aluminum tank to an new steel one from China any day of the week. Let's see how many Chinese tanks made from old car bumpers are still around in 70 years like my WWII Oxygen tank. So the fellow below alarmed at this thought can take his new Chinese tank and I'll use my USA WWII bomber tank and we will both be happy.

Just be sure to install a pressure relief valve as someone stated below (always do that on any tank) so if there is a fire, the tank does not explode. The relief valve must be connected such that there is never a valve between the tank and the relief valve.

Best of luck.
I use a 30 pund propane tank as the primary reiever for my G-D 2CFM
compressoor. I removed the original valve and used the 3/4" NPT
opening as inlet, outlet and drain by mouting the tank upside down. It
cost me $3 for the compressor, 50 cents for the 1/2 HP motor and $70
for the safety valve, pressure switch and check valve. I have a
filter/pressure regulator fed, inverted 20 pound tank for regulated
source use and several 20 pound tanks for extra storage capacity/air
pigs.
Have I metioned how good it is to have compressed air available for
brad nailer, impact wrench,die grinder, spot sand blaster, needle
scaler, blow gun, etc.,etc.,etc.?

---

Gerry :-)}
London,Canada

On Wed, 12 Feb 2014 21:12:29 -0500, wrote:

On Wed, 12 Feb 2014 15:49:00 -0800 (PST), wrote:

I have a yellow WWII aluminum tank like you describe. My pop used it from 1940's until he passed away in 2001. I inherited it and used it since. I just bought a new Porter Cable compressor that pumps up to 150 psi. That is about 25 psi higher than dad or I either one ever used before so I was logging in to see if the rating 200 psi or so.

Dad later used a hot water tank for years and that was a real big improvement for volume. I too agree recycling is fine and do not believe that there is any issue as long as one uses equipment within design perimeters.

I far prefer a USA made WWII aluminum tank to an new steel one from China any day of the week. Let's see how many Chinese tanks made from old car bumpers are still around in 70 years like my WWII Oxygen tank. So the fellow below alarmed at this thought can take his new Chinese tank and I'll use my USA WWII bomber tank and we will both be happy.

Just be sure to install a pressure relief valve as someone stated below (always do that on any tank) so if there is a fire, the tank does not explode. The relief valve must be connected such that there is never a valve between the tank and the relief valve.

Best of luck.
I use a 30 pund propane tank as the primary reiever for my G-D 2CFM
compressoor. I removed the original valve and used the 3/4" NPT
opening as inlet, outlet and drain by mouting the tank upside down. It
cost me $3 for the compressor, 50 cents for the 1/2 HP motor and $70
for the safety valve, pressure switch and check valve. I have a
filter/pressure regulator fed, inverted 20 pound tank for regulated
source use and several 20 pound tanks for extra storage capacity/air
pigs.
Have I metioned how good it is to have compressed air available for
brad nailer, impact wrench,die grinder, spot sand blaster, needle
scaler, blow gun, etc.,etc.,etc.?

And I'd condemn both of those tanks if you can't get them Hydrotested
for safety. If they blow up in your face it's going to ruin your
month, if not the rest of the century.

The WW-II Oxygen Cylinder is probably one of those Strap-Reinforced
ones, they're going to take one look at and condemn flat out - and I'd
stop using it unless you have a BIG safety margin - like in a Diving
Tank built for 5000 PSI and you're only using it at 150 max.

They deliberately made those tanks as light as possible, figuring the
plane it was in wasn't going to make it 25 missions before either
getting shot down, crashed, or scrapped as too full of holes to fix.

The ex-Propane tank doesn't have that kind of safety margin - you
could put a regular Propane valve back in, and turn it in as an
Exchange at a Home Center. They'll test it before refilling.

Even a portable air carry cylinder is better - they give you a 12-year
"Dispose By" date, and then you dispose of it. Or buy a regular ASME
receiver tank, and send it in for a hydro when it comes due.

-- Bruce --

On Sun, 16 Feb 2014 23:50:19 -0800, "Bruce L. Bergman (munged human
readable)" wrote:

On Wed, 12 Feb 2014 21:12:29 -0500, wrote:

On Wed, 12 Feb 2014 15:49:00 -0800 (PST), wrote:

I have a yellow WWII aluminum tank like you describe. My pop used it from 1940's until he passed away in 2001. I inherited it and used it since. I just bought a new Porter Cable compressor that pumps up to 150 psi. That is about 25 psi higher than dad or I either one ever used before so I was logging in to see if the rating 200 psi or so.

Dad later used a hot water tank for years and that was a real big improvement for volume. I too agree recycling is fine and do not believe that there is any issue as long as one uses equipment within design perimeters.

I far prefer a USA made WWII aluminum tank to an new steel one from China any day of the week. Let's see how many Chinese tanks made from old car bumpers are still around in 70 years like my WWII Oxygen tank. So the fellow below alarmed at this thought can take his new Chinese tank and I'll use my USA WWII bomber tank and we will both be happy.

Just be sure to install a pressure relief valve as someone stated below (always do that on any tank) so if there is a fire, the tank does not explode. The relief valve must be connected such that there is never a valve between the tank and the relief valve.

Best of luck.
I use a 30 pund propane tank as the primary reiever for my G-D 2CFM
compressoor. I removed the original valve and used the 3/4" NPT
opening as inlet, outlet and drain by mouting the tank upside down. It
cost me $3 for the compressor, 50 cents for the 1/2 HP motor and $70
for the safety valve, pressure switch and check valve. I have a
filter/pressure regulator fed, inverted 20 pound tank for regulated
source use and several 20 pound tanks for extra storage capacity/air
pigs.
Have I metioned how good it is to have compressed air available for
brad nailer, impact wrench,die grinder, spot sand blaster, needle
scaler, blow gun, etc.,etc.,etc.?

And I'd condemn both of those tanks if you can't get them Hydrotested
for safety. If they blow up in your face it's going to ruin your
month, if not the rest of the century.

The WW-II Oxygen Cylinder is probably one of those Strap-Reinforced
ones, they're going to take one look at and condemn flat out - and I'd
stop using it unless you have a BIG safety margin - like in a Diving
Tank built for 5000 PSI and you're only using it at 150 max.

They deliberately made those tanks as light as possible, figuring the
plane it was in wasn't going to make it 25 missions before either
getting shot down, crashed, or scrapped as too full of holes to fix.

The ex-Propane tank doesn't have that kind of safety margin - you
could put a regular Propane valve back in, and turn it in as an
Exchange at a Home Center. They'll test it before refilling.

Even a portable air carry cylinder is better - they give you a 12-year
"Dispose By" date, and then you dispose of it. Or buy a regular ASME
receiver tank, and send it in for a hydro when it comes due.

-- Bruce --
Refillable propane tanks are spec'd at a working pressure of 250PSI
and a burst pressure of 500psi. One tank out of every hundred or so
needs to be tested to either 3 times working pressure or twice burst
pressure for certification purposes.

actually ""Performance and integrity of the propane cylinders were
established by burst testing each of the 236 test cylinders. The
minimum design burst pressure criterion used here is 960 psi, or four
times the service pressure of 240 psi, consistent with typical DOT
requirements" from
http://www.propanecouncil.org/files/...port_Final.pdf

On Mon, 17 Feb 2014 07:43:52 -0500, wrote:

On Sun, 16 Feb 2014 23:50:19 -0800, "Bruce L. Bergman (munged human
readable)" wrote:

On Wed, 12 Feb 2014 21:12:29 -0500, wrote:

On Wed, 12 Feb 2014 15:49:00 -0800 (PST), wrote:

I have a yellow WWII aluminum tank like you describe. My pop used it from 1940's until he passed away in 2001. I inherited it and used it since. I just bought a new Porter Cable compressor that pumps up to 150 psi. That is about 25 psi higher than dad or I either one ever used before so I was logging in to see if the rating 200 psi or so.

Dad later used a hot water tank for years and that was a real big improvement for volume. I too agree recycling is fine and do not believe that there is any issue as long as one uses equipment within design perimeters.

I far prefer a USA made WWII aluminum tank to an new steel one from China any day of the week. Let's see how many Chinese tanks made from old car bumpers are still around in 70 years like my WWII Oxygen tank. So the fellow below alarmed at this thought can take his new Chinese tank and I'll use my USA WWII bomber tank and we will both be happy.

Just be sure to install a pressure relief valve as someone stated below (always do that on any tank) so if there is a fire, the tank does not explode. The relief valve must be connected such that there is never a valve between the tank and the relief valve.

Best of luck.
I use a 30 pund propane tank as the primary reiever for my G-D 2CFM
compressoor. I removed the original valve and used the 3/4" NPT
opening as inlet, outlet and drain by mouting the tank upside down. It
cost me $3 for the compressor, 50 cents for the 1/2 HP motor and $70
for the safety valve, pressure switch and check valve. I have a
filter/pressure regulator fed, inverted 20 pound tank for regulated
source use and several 20 pound tanks for extra storage capacity/air
pigs.
Have I metioned how good it is to have compressed air available for
brad nailer, impact wrench,die grinder, spot sand blaster, needle
scaler, blow gun, etc.,etc.,etc.?

And I'd condemn both of those tanks if you can't get them Hydrotested
for safety. If they blow up in your face it's going to ruin your
month, if not the rest of the century.

The WW-II Oxygen Cylinder is probably one of those Strap-Reinforced
ones, they're going to take one look at and condemn flat out - and I'd
stop using it unless you have a BIG safety margin - like in a Diving
Tank built for 5000 PSI and you're only using it at 150 max.

They deliberately made those tanks as light as possible, figuring the
plane it was in wasn't going to make it 25 missions before either
getting shot down, crashed, or scrapped as too full of holes to fix.

The ex-Propane tank doesn't have that kind of safety margin - you
could put a regular Propane valve back in, and turn it in as an
Exchange at a Home Center. They'll test it before refilling.

Even a portable air carry cylinder is better - they give you a 12-year
"Dispose By" date, and then you dispose of it. Or buy a regular ASME
receiver tank, and send it in for a hydro when it comes due.

-- Bruce --
Refillable propane tanks are spec'd at a working pressure of 250PSI
and a burst pressure of 500psi. One tank out of every hundred or so
needs to be tested to either 3 times working pressure or twice burst
pressure for certification purposes.

actually ""Performance and integrity of the propane cylinders were
established by burst testing each of the 236 test cylinders. The
minimum design burst pressure criterion used here is 960 psi, or four
times the service pressure of 240 psi, consistent with typical DOT
requirements" from
http://www.propanecouncil.org/files/...port_Final.pdf

Actually it is -
_FS-10202 Pressure ReliefValveandPropaneCylinderPerformanceTesting.pd f

On Mon, 17 Feb 2014 07:43:52 -0500, wrote:

On Sun, 16 Feb 2014 23:50:19 -0800, "Bruce L. Bergman (munged human
readable)" wrote:

On Wed, 12 Feb 2014 21:12:29 -0500, wrote:

On Wed, 12 Feb 2014 15:49:00 -0800 (PST), wrote:

I have a yellow WWII aluminum tank like you describe. My pop used it from 1940's until he passed away in 2001. I inherited it and used it since. I just bought a new Porter Cable compressor that pumps up to 150 psi. That is about 25 psi higher than dad or I either one ever used before so I was logging in to see if the rating 200 psi or so.

Dad later used a hot water tank for years and that was a real big improvement for volume. I too agree recycling is fine and do not believe that there is any issue as long as one uses equipment within design perimeters.

I far prefer a USA made WWII aluminum tank to an new steel one from China any day of the week. Let's see how many Chinese tanks made from old car bumpers are still around in 70 years like my WWII Oxygen tank. So the fellow below alarmed at this thought can take his new Chinese tank and I'll use my USA WWII bomber tank and we will both be happy.

Just be sure to install a pressure relief valve as someone stated below (always do that on any tank) so if there is a fire, the tank does not explode. The relief valve must be connected such that there is never a valve between the tank and the relief valve.

Best of luck.
I use a 30 pund propane tank as the primary reiever for my G-D 2CFM
compressoor. I removed the original valve and used the 3/4" NPT
opening as inlet, outlet and drain by mouting the tank upside down. It
cost me $3 for the compressor, 50 cents for the 1/2 HP motor and $70
for the safety valve, pressure switch and check valve. I have a
filter/pressure regulator fed, inverted 20 pound tank for regulated
source use and several 20 pound tanks for extra storage capacity/air
pigs.
Have I metioned how good it is to have compressed air available for
brad nailer, impact wrench,die grinder, spot sand blaster, needle
scaler, blow gun, etc.,etc.,etc.?

And I'd condemn both of those tanks if you can't get them Hydrotested
for safety. If they blow up in your face it's going to ruin your
month, if not the rest of the century.

The WW-II Oxygen Cylinder is probably one of those Strap-Reinforced
ones, they're going to take one look at and condemn flat out - and I'd
stop using it unless you have a BIG safety margin - like in a Diving
Tank built for 5000 PSI and you're only using it at 150 max.

They deliberately made those tanks as light as possible, figuring the
plane it was in wasn't going to make it 25 missions before either
getting shot down, crashed, or scrapped as too full of holes to fix.

The ex-Propane tank doesn't have that kind of safety margin - you
could put a regular Propane valve back in, and turn it in as an
Exchange at a Home Center. They'll test it before refilling.

Even a portable air carry cylinder is better - they give you a 12-year
"Dispose By" date, and then you dispose of it. Or buy a regular ASME
receiver tank, and send it in for a hydro when it comes due.

-- Bruce --
Refillable propane tanks are spec'd at a working pressure of 250PSI
and a burst pressure of 500psi. One tank out of every hundred or so
needs to be tested to either 3 times working pressure or twice burst
pressure for certification purposes.

actually ""Performance and integrity of the propane cylinders were
established by burst testing each of the 236 test cylinders. The
minimum design burst pressure criterion used here is 960 psi, or four
times the service pressure of 240 psi, consistent with typical DOT
requirements" from
http://www.propanecouncil.org/files/...port_Final.pdf

Available at:

http://ebookbrowsee.net/fs-10202-pre...pdf-d160377771

On Mon, 17 Feb 2014 08:24:24 -0500, wrote:

On Mon, 17 Feb 2014 07:43:52 -0500, wrote:

On Sun, 16 Feb 2014 23:50:19 -0800, "Bruce L. Bergman (munged human
readable)" wrote:

And I'd condemn both of those tanks if you can't get them Hydrotested
for safety. If they blow up in your face it's going to ruin your
month, if not the rest of the century.


Refillable propane tanks are spec'd at a working pressure of 250PSI
and a burst pressure of 500psi. One tank out of every hundred or so
needs to be tested to either 3 times working pressure or twice burst
pressure for certification purposes.

actually ""Performance and integrity of the propane cylinders were
established by burst testing each of the 236 test cylinders. The
minimum design burst pressure criterion used here is 960 psi, or four
times the service pressure of 240 psi, consistent with typical DOT
requirements" from
http://www.propanecouncil.org/files/...port_Final.pdf

Actually it is -
_FS-10202 Pressure ReliefValveandPropaneCylinderPerformanceTesting.pd f

Propane is supposed to be water and oxygen free, and the inside of
50-year old bottles should be pristine steel - and they come un-lined.
Air receivers are the exact opposite - that's why they get painted or
other corrosion coating on the inside before sale, and why they have a
drain valve and 2" inspection ports with plugs.

Propane bottles /used as/ air receivers don't have any anti-corrosion
coating on the inside, or inspection ports, or drain ports and valves
to regularly remove the condensate. That is a recipe for disaster.

If you welded in a 1/4" NPT port for a drain valve and a 2" inspection
port in a new propane tank and got the inside painted, then I
wouldn't have any arguments with repurposing it into an air receiver.
But your homeowners insurance company might.

-- Bruce --

In article , Bruce L.
Bergman (munged human readable)
wrote:

On Mon, 17 Feb 2014 08:24:24 -0500, wrote:

On Mon, 17 Feb 2014 07:43:52 -0500, wrote:

On Sun, 16 Feb 2014 23:50:19 -0800, "Bruce L. Bergman (munged human
readable)" wrote:

And I'd condemn both of those tanks if you can't get them Hydrotested
for safety. If they blow up in your face it's going to ruin your
month, if not the rest of the century.


Refillable propane tanks are spec'd at a working pressure of 250PSI
and a burst pressure of 500psi. One tank out of every hundred or so
needs to be tested to either 3 times working pressure or twice burst
pressure for certification purposes.

actually ""Performance and integrity of the propane cylinders were
established by burst testing each of the 236 test cylinders. The
minimum design burst pressure criterion used here is 960 psi, or four
times the service pressure of 240 psi, consistent with typical DOT
requirements" from
http://www.propanecouncil.org/files/...port_Final.pdf

Actually it is -
_FS-10202 Pressure ReliefValveandPropaneCylinderPerformanceTesting.pd f

Propane is supposed to be water and oxygen free, and the inside of
50-year old bottles should be pristine steel - and they come un-lined.
Air receivers are the exact opposite - that's why they get painted or
other corrosion coating on the inside before sale, and why they have a
drain valve and 2" inspection ports with plugs.

Propane bottles /used as/ air receivers don't have any anti-corrosion
coating on the inside, or inspection ports, or drain ports and valves
to regularly remove the condensate. That is a recipe for disaster.

If you welded in a 1/4" NPT port for a drain valve and a 2" inspection
port in a new propane tank and got the inside painted, then I
wouldn't have any arguments with repurposing it into an air receiver.
But your homeowners insurance company might.

So, what if one uses the propane bottle upsidedown, with a drain valve
at the bottom of a bit of iron pipe, and the air fittings on a T off
the vertical drainpipe?

(I don't plan on doing this, but it seems the obvious question to me.)

Joe Gwinn

"Joe Gwinn" wrote in message
...

So, what if one uses the propane bottle upsidedown, with a drain
valve
at the bottom of a bit of iron pipe, and the air fittings on a T off
the vertical drainpipe?

(I don't plan on doing this, but it seems the obvious question to
me.)

Joe Gwinn

The air inside will still be at 100% humidity.

This shows the vapor pressure of water versus temperature, equivalent
to 100% humidity. Atmospheric pressure is 760mm of Mercury:
http://hyperphysics.phy-astr.gsu.edu...kin/satvap.gif

When the compressor forces 10 gallons of air + water vapor into a 1
gallon tank the excess water will condense into liquid until its vapor
pressure falls to the line.
jsw

On 2/17/2014 1:50 AM, Bruce L. Bergman (munged human readable) wrote:
On Wed, 12 Feb 2014 21:12:29 -0500, wrote:
On Wed, 12 Feb 2014 15:49:00 -0800 (PST), wrote:
....

I use a 30 pund propane tank as the primary reiever for my G-D 2CFM
compressoor. I removed the original valve and used the 3/4" NPT
opening as inlet, outlet and drain by mouting the tank upside down. ...
....

And I'd condemn both of those tanks if you can't get them Hydrotested
for safety. If they blow up in your face it's going to ruin your
month, if not the rest of the century.

For typical compressed air setpoints of 100 psi +/- the pressure rating
for the propane tank is well within a margin of safety for burst
pressure, not to mention that he installed a relief valve besides.

The thought somebody has of eventually rusting thru will result in a
leak perhaps at some point but the likelihood of a destructive explosive
event is miniscule at best.


The WW-II Oxygen Cylinder is probably one of those Strap-Reinforced
ones, they're going to take one look at and condemn flat out - and I'd
stop using it unless you have a BIG safety margin - like in a Diving
Tank built for 5000 PSI and you're only using it at 150 max.

....

We've also had one of the AF "bubbles" that we use as a carry-all
portable supply on the farm. It's been around as long as I can remember
from the early 60s and is also nothing I'd worry about at all. Again,
the max that one can get into it is the outlet of the filling compressor
in our case (105 psi) or the cutoff of a compressor pressure switch if
used as a receiver. There's a rating stamped on this one but I don't
recall precisely what it is but I'm sure it's well above 100 psi.

All the discussion here is basically a "tempest in a teapot" as for real
safety concern imo.

--

On 2/21/2014 11:45 AM, dpb wrote:
....

We've also had one of the AF "bubbles" that we use as a carry-all
portable supply on the farm. It's been around as long as I can remember
....
... There's a rating stamped on this one ...

Well, I surely thought I remember that there was but isn't so...just was
out there where it is and remembered to look. But, I still have
absolutely no concern on using it for the purpose--it's served 50+ yr
and have no doubt it would continue to do so for that much longer
assuming it's not grossly mistreated.

--

On Fri, 21 Feb 2014 10:31:49 -0500, Joe Gwinn
wrote:

In article , Bruce L.
Bergman (munged human readable)
wrote:

On Mon, 17 Feb 2014 08:24:24 -0500, wrote:

On Mon, 17 Feb 2014 07:43:52 -0500, wrote:

On Sun, 16 Feb 2014 23:50:19 -0800, "Bruce L. Bergman (munged human
readable)" wrote:

And I'd condemn both of those tanks if you can't get them Hydrotested
for safety. If they blow up in your face it's going to ruin your
month, if not the rest of the century.


Refillable propane tanks are spec'd at a working pressure of 250PSI
and a burst pressure of 500psi. One tank out of every hundred or so
needs to be tested to either 3 times working pressure or twice burst
pressure for certification purposes.

actually ""Performance and integrity of the propane cylinders were
established by burst testing each of the 236 test cylinders. The
minimum design burst pressure criterion used here is 960 psi, or four
times the service pressure of 240 psi, consistent with typical DOT
requirements" from
http://www.propanecouncil.org/files/...port_Final.pdf

Actually it is -
_FS-10202 Pressure ReliefValveandPropaneCylinderPerformanceTesting.pd f

Propane is supposed to be water and oxygen free, and the inside of
50-year old bottles should be pristine steel - and they come un-lined.
Air receivers are the exact opposite - that's why they get painted or
other corrosion coating on the inside before sale, and why they have a
drain valve and 2" inspection ports with plugs.

Propane bottles /used as/ air receivers don't have any anti-corrosion
coating on the inside, or inspection ports, or drain ports and valves
to regularly remove the condensate. That is a recipe for disaster.

If you welded in a 1/4" NPT port for a drain valve and a 2" inspection
port in a new propane tank and got the inside painted, then I
wouldn't have any arguments with repurposing it into an air receiver.
But your homeowners insurance company might.

So, what if one uses the propane bottle upsidedown, with a drain valve
at the bottom of a bit of iron pipe, and the air fittings on a T off
the vertical drainpipe?

(I don't plan on doing this, but it seems the obvious question to me.)

Joe Gwinn
You would definitely not be the first - or the last - to do it that
way. I drillled a hole dead center of the bottom of the tank and
brazed in a fitting to accept a copper tube that comes out the side to
a ball-valve for draining.
The base of the tank is a neet fit into the rim of a "mini-spare"
which acts as the base, the rubber tire isolating the vibration of the
compressor from the floor. All my air goes in and out the main fitting
on the top, where I made up a manifold of pipe fittings. The base for
the compressor and motor is welded to the "cage" that originally
protected the valve.

On Fri, 21 Feb 2014 11:45:34 -0600, dpb wrote:

On 2/17/2014 1:50 AM, Bruce L. Bergman (munged human readable) wrote:
On Wed, 12 Feb 2014 21:12:29 -0500, wrote:
On Wed, 12 Feb 2014 15:49:00 -0800 (PST), wrote:
...

I use a 30 pund propane tank as the primary reiever for my G-D 2CFM
compressoor. I removed the original valve and used the 3/4" NPT
opening as inlet, outlet and drain by mouting the tank upside down. ...
...

And I'd condemn both of those tanks if you can't get them Hydrotested
for safety. If they blow up in your face it's going to ruin your
month, if not the rest of the century.

For typical compressed air setpoints of 100 psi +/- the pressure rating
for the propane tank is well within a margin of safety for burst
pressure, not to mention that he installed a relief valve besides.

The thought somebody has of eventually rusting thru will result in a
leak perhaps at some point but the likelihood of a destructive explosive
event is miniscule at best.


The WW-II Oxygen Cylinder is probably one of those Strap-Reinforced
ones, they're going to take one look at and condemn flat out - and I'd
stop using it unless you have a BIG safety margin - like in a Diving
Tank built for 5000 PSI and you're only using it at 150 max.

...

We've also had one of the AF "bubbles" that we use as a carry-all
portable supply on the farm. It's been around as long as I can remember
from the early 60s and is also nothing I'd worry about at all. Again,
the max that one can get into it is the outlet of the filling compressor
in our case (105 psi) or the cutoff of a compressor pressure switch if
used as a receiver. There's a rating stamped on this one but I don't
recall precisely what it is but I'm sure it's well above 100 psi.

All the discussion here is basically a "tempest in a teapot" as for real
safety concern imo.

I have observed though, that those who lack experience are prone to
imagine the largest catastrophes.
--
Cheers,

John B.

On Fri, 21 Feb 2014 10:49:48 -0500, "Jim Wilkins"
wrote:

"Joe Gwinn" wrote in message
...

So, what if one uses the propane bottle upsidedown, with a drain
valve
at the bottom of a bit of iron pipe, and the air fittings on a T off
the vertical drainpipe?

(I don't plan on doing this, but it seems the obvious question to
me.)

Joe Gwinn

The air inside will still be at 100% humidity.

This shows the vapor pressure of water versus temperature, equivalent
to 100% humidity. Atmospheric pressure is 760mm of Mercury:
http://hyperphysics.phy-astr.gsu.edu...kin/satvap.gif

When the compressor forces 10 gallons of air + water vapor into a 1
gallon tank the excess water will condense into liquid until its vapor
pressure falls to the line.

I have a couple of air pigs retrieved from an old poly foam dispensing
setup. They're nylon coated and have lasted nearly 40 years now. In
all that time, I've removed maybe 2 drops of water from them. I shake
them and never seem to hear liquid inside. They're filled from my main
HF 30gal upright compressor and used as mobile tanks. I haul the
little IR 3/4hp pump to refill them at remote sites when necessary.

Why couldn't someone use a jug of gas tank protective coating to make
a propane tank safer? They're already rated for 120PSI. Running
them upside down and ported for water removal is another good (and
easy to accomplish) task.

--
Cogito, ergo armatum sum.

(I think, therefore I am armed.)

"Larry Jaques" wrote in message
...
On Fri, 21 Feb 2014 10:49:48 -0500, "Jim Wilkins"
wrote:

"Joe Gwinn" wrote in message
.. .

So, what if one uses the propane bottle upsidedown, with a drain
valve
at the bottom of a bit of iron pipe, and the air fittings on a T
off
the vertical drainpipe?

(I don't plan on doing this, but it seems the obvious question to
me.)

Joe Gwinn

The air inside will still be at 100% humidity.

This shows the vapor pressure of water versus temperature,
equivalent
to 100% humidity. Atmospheric pressure is 760mm of Mercury:
http://hyperphysics.phy-astr.gsu.edu...kin/satvap.gif

When the compressor forces 10 gallons of air + water vapor into a 1
gallon tank the excess water will condense into liquid until its
vapor
pressure falls to the line.

I have a couple of air pigs retrieved from an old poly foam
dispensing
setup. They're nylon coated and have lasted nearly 40 years now. In
all that time, I've removed maybe 2 drops of water from them. I
shake
them and never seem to hear liquid inside. They're filled from my
main
HF 30gal upright compressor and used as mobile tanks. I haul the
little IR 3/4hp pump to refill them at remote sites when necessary.

Why couldn't someone use a jug of gas tank protective coating to
make
a propane tank safer? They're already rated for 120PSI. Running
them upside down and ported for water removal is another good (and
easy to accomplish) task.

The compressed air in your HF tank contains the same amount of water
vapor per gallon that outside air at the same temperature could hold
at 100% humidity. When you let that air expand into a lower pressure
tank the volume increases and that water vapor content falls below the
saturated pressure line, equal to a lower relative humidity. 100%
humidity in one gallon becomes 50% when it expands into two gallons.

A non-intuitive property of gases is that they ignore the presence of
other gases and each behave as if they were alone in the container,
like songbirds and rabbits living on the same land.
https://chemistry.osu.edu/~woodward/...10_mixture.htm

I've sloshed LPS-3 around inside steel air and water tanks and baked
them dry in the sun. The water tank rusted through after a few years.
The drain water from the air tanks shows only slight rust
discoloration.

jsw