Liquid oxygen

admin

Liquid oxygen, that is what a coworker told me you would get if you used an oxygen cylinder in the horizontal position. I'm not one to argue when I'm pretty sure I know the reality of the situation so I moved on to another subject. I know for a fact I have seen and used more than one rig setup with the O2 horizontal.I know acetylene must not be horizontal, acetone blah, blah, blah. And yes I used the search feature and read other threads about horizontal bottles before posting, one in particular turned into a "you're a big fat stupid head" match. Let us please avoid such, the net and this forum in particular, should at all times be a place of zen and enlightenment. Ranger 250 GXTSmith Gas Axe
Reply:O2 goes liquid at high pressure or low temps. O2 liquefies at -175 deg Celsius and at pressures over about 3800psi IIRC.Welding cylinders are seldom more than 2400 psi, well below the pressure threshold to liquefy O2.Liquid or cryo O2 is used in some manifold systems, but the O2 supplied is gaseous. The O2 evaporates from the liquid and is used that way.Liquid O2 is extremely dangerous as almost any material can ignite in the presence of 100% liquid O2 if conditions are right..No government ever voluntarily reduces itself in size. Government programs, once launched, never disappear. Actually, a government bureau is the nearest thing to eternal life we'll ever see on this earth! Ronald Reagan
Reply:But you won't get that out of a high pressure gas bottle. You'd need a special dewar container to hold and store the liquid.
Reply:Only compressed gasses are found in compressed gas cylinders.   There are bulk liquid tanks for oxygen, argon, nitrogen, propane and others.  CO2 and propane are the ones usually stored as a liquid in small cylinders.Last edited by DesertRider33; 08-20-2009 at 07:40 AM.MM350P/Python/Q300MM175/Q300DialarcHFHTP MIG200PowCon300SMHypertherm380ThermalArc185Purox oaF350CrewCab4x4LoadNGo utilitybedBobcat250XMT304/Optima/SpoolmaticSuitcase12RC/Q300Suitcase8RC/Q400Passport/Q300Smith op
Reply:Not much pressure in Liquid O2 containers.  We used liquid O2 to refill oxygen reservoirs on military aircraft.  Max pressure was about 35psi, refill pressures were always between 12-18psi.  Special containers with a vacuum liner were used to house the O2 in a liquid state.  Use of liquid O2 allowed for longer times between refills which in turn allowed longer flight times if inflight refueling is considered.MarkI haven't always been a nurse........Craftsman 12"x36" LatheEnco G-30B MillHobart Handler 175Lincoln WeldandPower 225 AC/DC G-7 CV/CCAdd a Foot Pedal to a Harbor Freight Chicago Electric 165A DC TIG PapaLion's Gate Build
Reply:Interesting Mark. I used to run a gaseous O2 booster where I worked. After we had an issue with the unit, we called the manufacture and asked about the problem. Their response was that the units were frequently used by airlines to refill in flight O2 bottles and that what we experienced happened rather frequently with them so it was no big surprise. I wonder why they didn't use liquid O2 for the same reasons you suggested..No government ever voluntarily reduces itself in size. Government programs, once launched, never disappear. Actually, a government bureau is the nearest thing to eternal life we'll ever see on this earth! Ronald Reagan
Reply:The O2 "tanks" were actually a rubbery material wrapped in a sphere shape with Stainless Steel wire to form the ball.  Then there was a (don't know exact dimension) approximately 1/2" between the stainless steel ball & outer housing.  This space allowed for a vacuum to be created (about -17 atmospheres) to maintain the shape of the inner liner.I don't know exactly what the inner liner was made of, but I do know it was flexible.  F-4 Phantoms held 7 liters of Liquid Oxygen, F-111's held 11 Liters.  If I remember correct the F-14 Tomcat held the same 11 liters of O2.Any liquid oxygen coming in contact with even a drop of any type of petroleum product will explode violently.  In fact in WWII special incendiary bombs were dropped with the rear half filled with any type of oil, the front portion held about 2 gallons of Liquid Oxygen.  Upon impact the oxygen instantly mixed with the oil & major fireball.  With the extra oxygen it burned even when the blast created a vacuum.  Almost like a mix of napalm & magnesium.  Dresden was bombed with this type of stuff.Most commercial airliners won't allow liquid O2, due to this volatility.  Too dang dangerous for simple ramp jockies.  Military training was different though.  We even had stainless steel "cookie sheets" about 3'x5' to hold the overflow.........just in case we were venting onto an asphalt ramp!  Had to let the liquid boil off before we moved it though.Look here for the Barlow Bomb: http://www.globalsecurity.org/milita...arlow-bomb.htmLast edited by MarkBall2; 08-20-2009 at 10:51 PM.MarkI haven't always been a nurse........Craftsman 12"x36" LatheEnco G-30B MillHobart Handler 175Lincoln WeldandPower 225 AC/DC G-7 CV/CCAdd a Foot Pedal to a Harbor Freight Chicago Electric 165A DC TIG PapaLion's Gate Build
Reply:My buddy that owns my lws has a o2 fill station, fills liquid tanks as well as compressed gas cyls. Liquid containers are stainless and vacuum insulated. Pressures are not high, the vessels relief valves are about 150psi. If liquid warms it turns into gas which is reason for vacuum insulation and relief valve. One of his employees broke a line on storage vessel and he lost about 2000 gallons. He called me to help replumb and braze a few lines that afternoon so new shipment could be sent in morning. The slab under vessel was so cold that I had to keep moving so my boots wouldn't freeze to concrete. When tank was leaking there was a fog about 3-4 feet deep for about 50 feet around. Was a strange sight.Peter
Reply:Yep, when the airplane O2 tank would fill & start venting, it was like a white jet out of the bottom of the plane.  Scared the snot out of a few crewchiefs the first time or two it happened during training.After a while it was expected & we could almost time it when it would start venting.  Stationed at Nellis (Las Vegas) in August, we all wanted to refill the O2 canisters so we could get some relief from the heat......even for a few seconds.Dang Peter, I wouldn't have done it myself and I've done some downright dangerous stuff.MarkI haven't always been a nurse........Craftsman 12"x36" LatheEnco G-30B MillHobart Handler 175Lincoln WeldandPower 225 AC/DC G-7 CV/CCAdd a Foot Pedal to a Harbor Freight Chicago Electric 165A DC TIG PapaLion's Gate Build
Reply:Originally Posted by MarkBall2Yep, when the airplane O2 tank would fill & start venting, it was like a white jet out of the bottom of the plane.  Scared the snot out of a few crewchiefs the first time or two it happened during training.After a while it was expected & we could almost time it when it would start venting.  Stationed at Nellis (Las Vegas) in August, we all wanted to refill the O2 canisters so we could get some relief from the heat......even for a few seconds.Dang Peter, I wouldn't have done it myself and I've done some downright dangerous stuff.
Reply:Originally Posted by MarkBall2Any liquid oxygen coming in contact with even a drop of any type of petroleum product will explode violently.  In fact in WWII special incendiary bombs were dropped with the rear half filled with any type of oil, the front portion held about 2 gallons of Liquid Oxygen.  Upon impact the oxygen instantly mixed with the oil & major fireball.  With the extra oxygen it burned even when the blast created a vacuum.  Almost like a mix of napalm & magnesium.  Dresden was bombed with this type of stuff.
Reply:Well, I was told about Dresden by a WWII vet that was also a bomber mechanic.  Don't know if it's true, but the blast area was much more powerful than many conventional weapons at the time.  It was also one of the early "air burst" bombs.Here's a couple pics of Liquid Oxygen I'm familiar with.............1.  Filling an F-16 with LOX2.  LOX container Attached ImagesMarkI haven't always been a nurse........Craftsman 12"x36" LatheEnco G-30B MillHobart Handler 175Lincoln WeldandPower 225 AC/DC G-7 CV/CCAdd a Foot Pedal to a Harbor Freight Chicago Electric 165A DC TIG PapaLion's Gate Build
Reply:Hmm... thinking about this it almost sounds like a thermobaric weapon or fuel-air bomb used today to take out caves and bunkers. The difference being these are usually quite large, where the munitions I have seen dropped on cities in WWII on film looked very small in comparison..No government ever voluntarily reduces itself in size. Government programs, once launched, never disappear. Actually, a government bureau is the nearest thing to eternal life we'll ever see on this earth! Ronald Reagan