Two single stage regulators prevent end of tank dump??

[Nick_593]

Hi would two single stage regulators serve the same function as a dual stage regulator(?), and if so would this prevent end of tank dump?

Thanks

 

[ian_m]

Don't think so.

A dual stage generally drops the tank pressure (say 55bar) to say 10bar in first stage then to 0-5 bar in a controllable second stage.

There are actually a couple of ways single stage regulators are produced. Some actually use pressure regulation (a single stage of above type) but some are just "flow controllers" and reduce the pressure by passing the gas through either a small hole or sometimes a compressed metal sponge. It is the second type that suffer from end of tank dump, as the tank pressure drops the resistance to flow reduces and tank empties out. This is really handy if CO2 welding as increased flow of gas warns you your gas is about to run out, but maybe deadly to fish if your CO2 container is large.

I have a single stage CO2 regulator (CO2Supermarket) and as the CO2 tank runs out, the bubble rate starts dropping off, drop checker no longer as green/yellow as is should be and eventually flow just stops usually 3-4 days after I notice first change in bubble rate. Not as well regulated as a dual stage would probably be, but no end of tank dump and in its favour you get days warning your CO2 tank is running out.

 

[Andy Thurston]

Its not a regulator unless it reduces the pressure, more dodgy sales wording. Also I'd rather have a dual stage reg on my welder then i don't have the hassle of turning the service pressure down after every weld to avoid o2 being sucked into the gas shroud a good operator can tell when the gas is running out, by the appearance of the weld. a dual stage reg is even more critical with gas welding/cutting/brazing operations
Eotd happens with every type of welding gas i've used not just co2
As for op's original question co2art sell a second stage to add to a single stage reg to prevent eotd, so yes it can work