C02 reg freezing

[jimbo84]

I'm using a C02 extinguisher with a C02 reg. Used it the correct way up and it froze so assume it has a dip tube so started using it upside down but it's still getting very cold although not freezing up but it's affecting the output flow by increasing it when it does get cold.

Running at 10-15lpm but when it gets cold this rises to 25-30lpm.

 

[hotponyshoes]

The dip tube is normally spaced up from the bottom to stop it getting clogged up with rust etc so you might have to hold it upside down and discharge the liquid until just gas comes out

 

[Paul.]

Withdrawal rate is too high, in the good old days when we used CO2 for heavy fab work we had heaters on the valves.

 

[jimbo84]

I’ll make sure the dip tube is clear of liquid and try a lower flow rate and see if that helps.

 

[Wallace]

How many Amps is your machine and what thickness of material are you welding?

Run a couple of beads on some scrap material as you are currently welding with the existing setup. Keep turning the regulator down until the beads have bubble holes in them. Up the flow until they improve to find the sweet spot then add a little.

Depending on your regulator you will get a gush of gas when you first pull the trigger, this settles out to the flow rate after a couple of seconds to where you want to be.

 

[roofman]

I'm using a C02 extinguisher with a C02 reg. Used it the correct way up and it froze so assume it has a dip tube so started using it upside down but it's still getting very cold although not freezing up but it's affecting the output flow by increasing it when it does get cold.

Running at 10-15lpm but when it gets cold this rises to 25-30lpm.

The problem is the regulators have no brains and when the reg starts freezing then the pressure drops and this makes the reg think there is a pressure drop and increases pressure...viscous circle and i get this every day with propane in my job we try to insulate the reg from the outside air and we also sit the bottle in a big 30L tub of water which also reduces boil off and freezing of the bottle and reg.

 

[hotponyshoes]

i get this every day with propane in my job we try to insulate the reg from the outside air and we also sit the bottle in a big 30L tub of water which also reduces boil off and freezing of the bottle and reg.

If you get through enough propane to justify the initial outlay get a refillable tank. It will pay for itself (depending on how much you pay for the bottles now) but get a horizontal one as the larger surface area of the liquid gas helps with the cooling. I got one a couple of years ago and it's stopped all the problems I had with high use on the bottles

 

[jimbo84]

How many Amps is your machine and what thickness of material are you welding?

Run a couple of beads on some scrap material as you are currently welding with the existing setup. Keep turning the regulator down until the beads have bubble holes in them. Up the flow until they improve to find the sweet spot then add a little.

Depending on your regulator you will get a gush of gas when you first pull the trigger, this settles out to the flow rate after a couple of seconds to where you want to be.

It’s only a 30/85a transformer machine, I was running it on some 3mm just to practise some mig, not done it in over 10years. I’ll try turning it down and try and set a minimum flow.

The problem is the regulators have no brains and when the reg starts freezing then the pressure drops and this makes the reg think there is a pressure drop and increases pressure...viscous circle and i get this every day with propane in my job we try to insulate the reg from the outside air and we also sit the bottle in a big 30L tub of water which also reduces boil off and freezing of the bottle and reg.

I might try a bit of gentle heat on it, see if it helps.

 

[Badger1bear]

https://www.weldingandwelder.com/gas-regulators-manifold-systems-argonco2-heaters-c-209_449.html

https://www.weldingdirect.co.uk/Welding-Gas-Pre-heater-for-CO2---230Volt

http://www.gys-welding.co.uk/spip.php?page=produit&reference=046511&lang=uk

 

[hotponyshoes]

The c02 heater things will crack the elements if you run liquid co2 through them.

If you need really high flow rates on co2 try a beer regulator set to 50psi then a secondary regulator on a 50cm hose after the first one.
I can pull much higher lpm from one of those with no problems.

If you want to carry on using fire extinguishers and don't want to turn them upside down fit a vaporizer.
Might work out cheaper just to get a regular co2 bottle though.
For the price you could have 2 or 3 set up with quick connects and just swap as they freeze

Edit: not sure how good my beer maths is.
It might not actually be a very high flow rate at all...

 

[jimbo84]

I'm only using a fire extinguisher as I had a part discharged one and wasn't sure how well the welder would work so thought I'd use up the extinguisher before getting a cylinder but once it's run out it'll be on a proper cylinder.

 

[hotponyshoes]

If it's part discharged and upside down you shouldn't be getting any liquid out of it (once you have purged out what's in the tube which might be more than you think!)

Have you got a regular co2 regulator attached to it?
Is the regulator mounted the correct way up when in use?

 

[jimbo84]

I've got a c02 reg attached to it but I didn't realise they had to be a certain way up, it's flat at the moment, I guess that may be the issue and now you've mentioned it every reg I've seen always goes dials up, never thought anything of it... D'OH

This is the rig.

 

[hotponyshoes]

Try moving the reg around, might help?
I'm not sure if it will as I have used propane regs in all directions with out problems.
I know co2 beer regs have a small hole in the casing and the instructions always say they must be mounted with that facing down. Doing it that way always leaves the gauges at the top of the reg.

I have used argon regs sideways but that's a different thing altogether. I don't think the position of the actual gauges matter but it might be worth trying it with the adjuster knob rotated 90deg so it's horizontal rather than vertical?

 

[hotponyshoes]

It might also be worth trying to turn the welding wire upside down as well, in the photo it looks like it's bending the tube that goes into the wire feeder?
If you spin it over it might feed in a bit straighter?

An you might want brush off the small bits of swarf on that bench under the welder if there is any near the air intake otherwise it can get sucked in by the cooling fan and cause all sorts of problems

 

[jimbo84]

I'll try the reg in the more upright position and see if it helps.

The tube was naturally bent that way so I kept it that way as the other way with the wire bent it down so thought it best to keep it bent the way it was.

If it had a cooling fan I'd agree with you but it's far too basic for any of that fancy cooling trickery

Thanks for all the pointers, appreciate it, it's a top forum with a very helpful bunch of fellas (and ladies).