Dial Guage vs. Flowmeter

[Michael Nutt]

Which is better, Dial Guage or Flow meter? Also, how important is a Surge Check Valve?

[cope]

In theory the flow meter is more accurate than the gauge, but for welding I doubt it makes much difference. I have a flow meter on my MM210 and a gauge on my HH140. I already had the meter or I would have used the gauge that Miller supplied.

[Wheat]

Repeating the other posts. The flowmeter will be more accurate. Got a flowmeter on my bottle of argon for the tig. Got the regulator for the mig. Never noticed much difference from the regulator vs. flowmeter on the mig. If you got a few extra bucks, buy the flowmeter....IMHO

[CPB]

A check valve allows gasses to travel in one direction only, so if pressure on the torch side of the check valve exceeds the pressure on the supply side, the springed valve closes. Supposably this is will stop one flashback and then will have to be replaced for new check valves. They may stop one flash back but in doing so the springs are most likely destroyed making the valve useless. If a person is new to oxyfuel welding or cutting he may not recognize a flashback if it were to occur and continue welding or cutting with an 'unsafe line'. The next flashback could go past the burnt check valves into the regulators then into the supply tanks. I personally don't trust this setup.
The answer to this is to get a set of flashback arrestors.They stop the flame and are reusable. Even if your torch has them built in you should get a set mount on your guages if for example you or someone else were to change torches with one that does not have them already built in. Sometimes we do things without thinking, or at least I do. The cheaper ones stop the flame using a pourous stainless steel filter.More expensive ones use a water block to stop the flames.
CPB

[hankj]

The ball-in-tube flowmeter has been around for a long time in a lot of flow monitoring applications besides welding. It is recognized as the most accurate of the ball vs. guage comparison, simply beacause there is no variable, just the weight of the ball vs. spring, bearing and needle in the guage type. The precision is more important at very low flows. At flows as high as 25SCFH, it ain't no biggie.

As for the "Surge Check Valve", I've never heard of it. Someone, of course, has, and will respond, but my guess is it is intended to limit the initial flow as you transition from static pressure to residual pressure so there's no "puff". To me, it's superfluous.

Hank

[CPB]

Michael, Scratch my answer. I believe I made mistake. I also never heard of a Surge Check Valve and thought you were talking about something else. Sorry!
CPB