flowmeters

[oilcooled :)]

when i bought my mig, it came with the regulator that tells you whats in the bottle, but not whats going out, i bought a flowmeter, and have it set to 7 litres a min. the flowmeter is a c02 flowmeter, if im using that with cougar 5 20% c02 80%Ar would that be giving me a false reading, c02 would be a heavier gas wouldnt it? just curious the gas doesnt seem to last too long, if ive done a full hour of welding continualliously, id be amazed, and yet the pressure is at 120 bar, and when full it was 240, maybe i should open the machine and check inside, ??? its a new machine? using half size industrial bottle, the biggest 3 foot one

 

[mike 109444]

CO2 is a liquid under pressure so you get more gas for the same size of cylinder as argon CO2 mix (rem you have only 20% CO2 ) I have tried mix myself and though the weld was nicer that just CO2 I found the mix went a lot quicker. Also if you have even a slight leak/poor fitting then at 150 to 200 bar of mix compaired to 30(ish) bar of CO2 your losses will be more. I went back to CO2 as it's dirt cheep and easy to get.

 

[Rick]

7 litres a minute you used half a half size bottle in 1 hour?

That doesn't seem correct. IIRC the big bottles hold 11 m^3. or 11,000 litres. Half that, 5500litres. It should last you 12 hours of welding at that flow. You'd heave a leak if it was using that much gas.

 

[Robotstar5]

Pick up a peashooter type flow gauge, it checks the gas flow at the shroud.