Gas pressure

[Richard.]

Just below 6lpm on the reg just below 5lpm on the pea shooter. I'm sure they are both accurate where they are but there is a discrepancy somewhere. My reg was very expensive and every joint is leak tested. My line is over 2 metres long I'm sure it's possible at these low flow rates a reduction can be achieved through the line.

 

[backpurge]

I use a TVC digital flowmeter which is re calibrated annually at the torch end to test actual flow rates on a regular basis and more often than not there is a difference between the figure registered at the torch and that at the regulator mounted flowmeter.

 

[Richard.]

I'll be buying one of those I've heard they are really good

 

[Richard.]

I'll be buying one of those I've heard they are really good

For work Mind I've no need for kit that precise at home.

 

[Welderpaul]

People seem to get hung up on having the perfect gas flow rate.....For MIG, and even TIG to a degree, i don't think it really matters is you are a few L/M either way?

 

[Richard.]

People seem to get hung up on having the perfect gas flow rate.....For MIG, and even TIG to a degree, i don't think it really matters is you are a few L/M either way?

Your right Paul I guess I'm just phonetic about it because I like accuracy and I buy my own gas so I don't want to be using any more than I have to.

 

[eSCHEn]

A question for you: why do you need such an accurate flow rate?

Is it because you have to record that information for regulatory reasons or when you're running twenty welding stations the costs add up or something else?

Not a snide comment, I'm just a hobby welder so if it doesn't look like worm sign then I'm happy so I'm genuinely interested to know.

 

[Richard.]

A question for you: why do you need such an accurate flow rate?

Is it because you have to record that information for regulatory reasons or when you're running twenty welding stations the costs add up or something else?

Not a snide comment, I'm just a hobby welder so if it doesn't look like worm sign then I'm happy so I'm genuinely interested to know.

My job requires that sort of accuracy with all welding conditions and I take that same level of accuracy when welding from my own gear. I am technical support for a welding company and I do a lot of trials with conditions , consumables, process,equipment, gas, and accuracy is vital, also I'm a bit of a perfectionist with my own work and I like things to be bang on.

 

[Welderpaul]

My job requires that sort of accuracy with all welding conditions and I take that same level of accuracy when welding from my own gear. I am technical support for a welding company and I do a lot of trials with conditions , consumables, process,equipment, gas, and accuracy is vital, also I'm a bit of a perfectionist with my own work and I like things to be bang on.

The right attitude to have too.
Before we had multi stage regs i'd often find regs with sky high flow rates due to the speed at which we empty cylinders - never affected the welds, just my pocket.

 

[eSCHEn]

Thanks both for the posts, very interesting.

 

[backpurge]

It is normally for the benefit of the guy who signs the cheque for the gas at the end of the month, regularly see flow gas rates well over 20 ltr/min, highest I've come across is 75ltr/min. If you think about it, 20 guys all running at 25ltr/min are wasting around a cylinder of gas per hour

Also excessively low flow rates will allow nitrogen ingress into the weld pool which will reduce the strength in and around the HAZ long before you see porosity in the weld. I totally agree with the comments about people getting hung up about the accuracy of flow rates, more so with MIG/MAG than TIG and root purging

 

[Richard.]

The right attitude to have too.
Before we had twin stage regs i'd often find regs with sky high flow rates due to the speed at which we empty cylinders - never affected the welds, just my pocket.

Yeah some people don't give a t0$$ if it's not costing them. Good move with the multi stages.

 

[eSCHEn]

It is normally for the benefit of the guy who signs the cheque for the gas at the end of the month, regularly see flow gas rates well over 20 ltr/min, highest I've come across is 75ltr/min. If you think about it, 20 guys all running at 25ltr/min are wasting around a cylinder of gas per hour

Also excessively low flow rates will allow nitrogen ingress into the weld pool which will reduce the strength in and around the HAZ long before you see porosity in the weld. I totally agree with the comments about people getting hung up about the accuracy of flow rates, more so with MIG/MAG than TIG and root purging

I'd reckoned on it being cost related for exactly the reason you say but I'd not realised that there could be a strength issue that is unknown if you don't have the correct flow.

 

[Wallace]

View attachment 57216 Just below 6lpm on the reg View attachment 57217 just below 5lpm on the pea shooter. I'm sure they are both accurate where they are but there is a discrepancy somewhere. My reg was very expensive and every joint is leak tested. My line is over 2 metres long I'm sure it's possible at these low flow rates a reduction can be achieved through the line.

Differences in calibration between the flowmeters would be my first thought unless there is a leak within the machine, only way to tell is to check each flowmeter against a known source but the difference is negligible for the use. I found internal gas leaks on my Tig and Mig by upping the flowrate to increase the line pressure, blocking the torch and checking the regulator flowmeter had dropped to the bottom (which they didn't) and I could hear the leaks. Likely that under normal use there would have been minimal if any gas loss through the leaks but still annoying to find them in the first place, an overtightened hose clamp on the Tig and incorrect hose fitting for hose size on the Mig.

People seem to get hung up on having the perfect gas flow rate.....For MIG, and even TIG to a degree, i don't think it really matters is you are a few L/M either way?

Only from the cost point of view. I spent years adjusting the Mig by gas hiss sound and test welds, still do by habit and my gas usage has always been good but when I bought a gas guzzling Tig I decided some better control was needed.

 

[Richard.]

No leaks on my system I've throughly checked it with leak detector at every joint in the machine and the cooler and the torch unions. I'm happy with my gas usage I keep it to a minimum without compromising weld quality . I'll continue to set the flow on my reg and continue to check it with my pea shooter and fine tune it to that because it works well for me.

 

[Robotstar5]

Before we had multi stage regs i'd often find regs with sky high flow rates due to the speed at which we empty cylinders - never affected the welds, just my pocket.

In production welding it is common to find the flowguages maxed out (40+ lpm) as they believe the higher they can turn something up (weldsets included) the quicker they can finish we fitted tamperproof flow regs to all our manual welding booths.

 

[Richard.]

I think the calibration on my reg should be ok given its a £250 lump of brass. You can get flow decrease over the length of a 2 metre line and a 8 mtr Tig torch. That's 10mtrs it's flowing so I'd expect some reduction.

 

[eSCHEn]

In production welding it is common to find the flowguages maxed out (40+ lpm) as they believe the higher they can turn something up (weldsets included) the quicker they can finish we fitted tamperproof flow regs to all our manual welding booths.

What do you mean, it not like computers where the more times you press the button the faster it works? Gutted

 

[Wallace]

8m Tig torch? That's a long walk back to tweak the flowrate, does the £250 regulator include a remote control?

 

[Richard.]

What's wrong with an 8m Tig torch such things do exist for a reason. I don't have to have all 8 mtr unraveled but it's there if I need it. And no it doesn't have a remote. There is nothing wrong with my equipment or how it's used. I don't see what the issue is with using equipment properly and buying good gear to serve my purpose. The reg is brand new to replace my beloved murex saffire and I bought a multi stage optiflow to save my gas usage.