Gas bottle

admin

How is a good way to tell how much gas is in bottle.This is a large bottle used for mig welding.   thanks for your help
Reply:What kind of gas are we talking about? If its a mix gas just look on the high pressure gauge on the regulator or flowmeter. I use straight CO2 and it stays on 600# until it`s real low it starts showing below 600. It comes in liquid form in the bottle so the pressure stays the same until there is no more liquid.
Reply:And you can determine how full a CO2 bottle is by weighing it.  Weigh it on an accurate scale when it is full, then weigh it again when it is empty and mark the weights on the bottle.  The weight of the cylinder decreases linearly from full to empty weight in proportion to the amount of gas used.  Of course, always weigh in the same configuration (with or without regulator).awright
Reply:I weighed the bottle & it weigh's 185# without regulator The bottle is 75% argon &25% c02  I have only used a little couple times.This weight is with screw cap on   thanks for your help
Reply:The weight changes alot from full to empty for a liquid cylinder.   Compressed gas, which is what 75/25 is, doesn't change much in weight from full to empty.   I don't know that you would get a reading accurate enough to indicate anything on a compressed gas cylinder.MM350P/Python/Q300MM175/Q300DialarcHFHTP MIG200PowCon300SMHypertherm380ThermalArc185Purox oaF350CrewCab4x4LoadNGo utilitybedBobcat250XMT304/Optima/SpoolmaticSuitcase12RC/Q300Suitcase8RC/Q400Passport/Q300Smith op
Reply:The best way that I know of is to just check to gas pressure in the bottle.The simplest, and cheapest, way is to just use the HP gauge on the regulator as suggested above. If you don't have a HP gauge on the reg set, see if it has a port for one. You can build a "tank checker". However, as everything in the unit will be exposed to HP gas, expect to pay big $$ for all the parts. Basically you need the correct CGA fitting and nut, a HP port that will accept the gauge, A gauge, and some sort of HP bleeder/valve to reduce the pressure so it can be removed. Remember if you try and do this yourself, If you use the wrong parts, chances are high that it will blow apart under the pressure of a full tank, and injure or kill anyone nearby!I build HP gas systems, if you really need one pm me. I don't have any prices for what the parts would cost off the top of my head. My guess is $75+ at a minimum unless you can find one ready made.
Reply:My comment about weighing a bottle to determine its contents was specifically referring to pure CO2.  I know nothing about the behavior of gas mixes, but it will certainly not be as simple as straight CO2.As mentioned by Bob, CO2 liquifies at room temperature at a modest (by gas cylinder standards, at least) pressure of several hundred PSI.  As you draw off gas, the pressure in the bottle is slightly reduced and the liquid CO2 boils off more gas to bring the pressure back up to the equilibrium pressure for the present temperature of the liquid in the cylinder.  This is the reason you can't determine the contents of a pure CO2 bottle by reading pressure.  The pressure doesn't start dropping (at constant temperature) until the liquid is gone and the bottle is almost empty.The boiling of the liquid CO2 absorbs a definite amount of heat (the Latent Heat of Vaporization) from the surroundings, cooling the remaining liquid and the bottle.  At this lower temperature the pressure IS lower, but only temporarily until the tank and contents reach temperature equilibrium with the surroundings again.Because most other welding gasses do not liquify at room temperature at practical pressures, cylinder pressure is directly related to volume of gas in the cylinder (at constant temperature), so it is very practical to determine contents by simply reading the high pressure gauge on your regulator.  You could probably determine gaseous contents of a cylinder with a high precision scale and careful weighing, but why bother if you can do it with an inexpensive pressure gauge that is already at hand?awright
Reply:when your wire starts sputtering, and your welds are porous, your empty haha