Came to my possession an old argon regulator. the outlet flow gauge installed on it is a "Smith's H70D" gauge and it's funny because there isn't any indication of the units it showing, only 0 to 400. could you tell in which units and what will be the correct setting for argon on stainless steel welding? note - it's not on "0" because I've installed it on a cylinder, not because it's faulty.
- Thread starter amron
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The H70D gauge displays pressure in PSI (pounds per square inch). If this is the cylinder pressure gauge, then the range is rather low for argon, for which filled pressure will typically be somewhere between 100 and 200 Bar (1500 to 3000 PSI), or more.
0-400PSI would be more applicable for an acetylene cylinder, in which case, the bullnose fitting clamp screw should have a left hand thread (at least in the UK), whereas argon cylinders have a right hand threaded fitting.
0-400PSI would be more applicable for an acetylene cylinder, in which case, the bullnose fitting clamp screw should have a left hand thread (at least in the UK), whereas argon cylinders have a right hand threaded fitting.
BrokenBiker
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You don't set flow in psi...psi is pressure, not flow...you set flow to LPM (litres per minute) or CFH (cubic feet per hour)
Right, my mistake, what is the output pressure on PSI from the regulator that should be set on this gauge?
BrokenBiker
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There is no outlet pressure...there is flow...you need a gauge that reads flow.
A typical shielding gas regulator will have 1 non adjustable dial that reads bottle content pressure and one that is adjustable and reads flow. You set the flow to around 10lpm for mig welding or set it based on cup size for tig welding
A typical shielding gas regulator will have 1 non adjustable dial that reads bottle content pressure and one that is adjustable and reads flow. You set the flow to around 10lpm for mig welding or set it based on cup size for tig welding
I have a flowmeter installed on the regulator output (it's the one with the steel ball). what I meant (and maybe I'm not using the right terms) is to what pressure the regulator should be set (on the gauge that I've asked about) to which point between the 0 to 400 PSI for welding SS?
Judging by the replies, the regulator has been altered by someone who has put an entirely inappropriate gauge on the outlet pressure side. There is no knowing what else might have been done. The best thing to do would be to bin the regulator (or give it to a museum, with strict instructions for display only) and start afresh. The argon cylinder pressures are not to be messed with, and regulators have a finite useful and safe life. If a regulator goes "bang" it can literally blow your face off. Better to be safe than sorry, or worse!
BrokenBiker
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You don't set the pressure...throw the reg in the bin and get a proper one
Please help me to understand. attached a pic of the regulator and it's gauges. as far as I can understand - the right gauge exhibits the cylinder's pressure. the gauge on the left exhibits the pressure that is reduced by the regulator (it's done by turning the screw with the handle on the center of the regulator) and then, after the reduced pressure was set, there is on the extreme left the vertical transparent flow meter which controls the amount of the gas flown to the torch. where am I wrong?
BrokenBiker
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Gonna say this 1 more time in the hope you read it slowly...you do not set the pressure coming out of the regulator...you set the flow, and that gauge does not read flow, which means it's the wrong gauge. The regulator has been tampered with or badly repaired and is no longer safe to use. Change it for a proper shielding gas regulator that reads flow. They are plenty cheap enough.
I've understood what you've wrote the first time. all I want now is to understand how it worked. I've got it from someone that worked with it for many years. it's not the question of buying a new one, it's not an issue, again, I would like to understand how it worked and logic of it.
BrokenBiker
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It is the wrong gauge, that's all there is to it. You say you understand but repeatedly ask the same question after being told why it's wrong...it may work, but it's not correct and the values in that dial are completely meaningless for a welder...
Looking at the state/age of that regulator it should have gone in the bin a fair while ago, they are not lifetime items
Erie Fred
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Ussually the regulator is fixed, there is no handle to twist.
IIRC those pre-set regulators are approx. 50 psi.
Try 50 psi and then set your flow using the needle valve at the bottom of the flowmeter.
Your flowmeter might even say on it what pressure to run it at.
BrokenBiker
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According to Wikipedia, it was around 2000 they merged with TI so possibly around then
hotponyshoes
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I'm not scared of blowing part of my face away by a pre war regulator exploding but I would be worried it was leaking the £130 argon out without me knowing about it..
With the gas flowing freely (outlet pipe disconnected or torch trigger pulled)
Open the tap on the pea shooter (ball tube gauge) all the way.
Open the bottle valve all the way.
Turn the knob on the regulator slowly until the ball is at the top marking on the tube.
From then on, don't touch the regulator again, adjust the flow with the knob on the ball tube.
If you really want to use that regulator and have a blank handy I'd take that gauge off as it's just a potential leak point.
With the gas flowing freely (outlet pipe disconnected or torch trigger pulled)
Open the tap on the pea shooter (ball tube gauge) all the way.
Open the bottle valve all the way.
Turn the knob on the regulator slowly until the ball is at the top marking on the tube.
From then on, don't touch the regulator again, adjust the flow with the knob on the ball tube.
If you really want to use that regulator and have a blank handy I'd take that gauge off as it's just a potential leak point.
