Gas Reg. - What Pressure Is What?

[Cocko]

Hello All,

I am trying to help a mate in NZ set up his new kegging system, and as we all were, he is pretty excited to pour one!

Anyway, here the issue; He bought a Gas Regulator form Trade Me [NZ Ebay] from a welding supplier... The welding supplier said they sell heaps into the brewing market... Anyway, see the pic below.

Can anyone tell me where 300kpa is? The gauge says x100 KPA so it goes up to 70, thats 7000kpa WTF?

I am thinking 30 is 300 but I don't want to blow him up :unsure:

Any advice would be awesome:

View attachment 29357

 

[Frank]

I would assume that gauge is the one for bottle pressure.
Tell him to turn the regulator all the way anti-clockwise and then turn the bottle on. Slowly turn the regulator clockwise and you should see the other gauge start move.

 

[Cocko]

I would assume that gauge is the one for bottle pressure.
Tell him to turn the regulator all the way anti-clockwise and then turn the bottle on. Slowly turn the regulator clockwise and you should see the other gauge start move.

Thanks Boston,

Yeah, the LPM gauge would be the bottle pressure/volume.

But what about the KPA gauge, when it does move what is 300 kpa? It says "x100" so 30 is 3,000 Kpa... surely not but I am just trying to be sure for him...

 

[Frank]

Ask your mate to send you the model number on the regulator box.
I would be guessing the LPM gauge is Litres per Minute, (flow rate) and the KPA gauge is for bottle pressure. I would say this is not the right regulator for brewing. I would guess it is the type used for a constant flow rate of CO2.

 

[paulwolf350]

Thanks Boston,

Yeah, the LPM gauge would be the bottle pressure/volume.

But what about the KPA gauge, when it does move what is 300 kpa? It says "x100" so 30 is 3,000 Kpa... surely not but I am just trying to be sure for him...

Lpm is litres per minute, a welding thing for how much gas is being let out of the end of the welding torch. The guage on the right is the bottle pressure.

for a home brew application you need to work out how many lpm you need through trial and error. Probably be a PITA because LPM is Flow whereas for kegging you really want pressure.

I threw mine away and bought a pressure guage, because i could not get it to work properly. someone with more patience might have more success though


hope this helps
Paul





edit : crap i am always just a bit too slow, double crap

 

[Cocko]

Thanks heaps guys.... Lucky it was cheap!

Ok, now to break the news! Lucky he is across the ditch!

Thanks again :icon_cheers:

 

[krusty_oz]

Since the supplier claims to have supplied brewers, he may know what the pressure each lpm is equavalent to on this gauge. If not I suspect there are a few brewers pulling their hair out trying to get their beer carbed up and dispensing right. I this case it might be possible to replace the lpm gauge with a kPa (say 0-700 kPa range) but would probably cost as much as a regulator with the right dials in the first place.

 

[Cocko]

Since the supplier claims to have supplied brewers, he may know what the pressure each lpm is equavalent to on this gauge. If not I suspect there are a few brewers pulling their hair out trying to get their beer carbed up and dispensing right. I this case it might be possible to replace the lpm gauge with a kPa (say 0-700 kPa range) but would probably cost as much as a regulator with the right dials in the first place.

Cheers Krusty_oz,

Agreed, I told him he has to ask the supplier for a conversion chart or something....

Poor dude, has his beer kegged, all ready to go and cant carb it or pour it!!

 

[Sammus]

surely there is no conversion for LPM to kpa... one is flow, as soon as the keg is pressurized the flow will drop to zero? or if it regulates the flow instead of pressure, well itll just keep filling up till it explodes.

if it does actually regulate the pressure (I don't know much about regs, like if you can even get one that regulates the flow) then just tell him to dial in just enough pressure to be able to fill a pint in about 10s or something (like a normal pour rate, whatever that might be) and just leave it at that pressure for a week and itll be good to go.

if it does regulate flow instead of pressure i dont think it could be safely adapted to work at all...as i said though, im not even sure such regulators exist, at least not cheap ones

 

[Gavo]

Yep LPM = litres per minute. I was looking at using my welding reg for beer but it had the wrong fitting. By lowering the LPM/flow rate you would be effectively lowering the pressure as the gas would need a higher pressure to flow at a higher rate. Us welding types need to know the flow rate of the gas rather than the pressure. I reckon you could still use it if you could fugure it out with a little PITA trial and error.

Gavo.

 

[krusty_oz]

You could try hooking up some hose to a tyre pressure gauge to convert the lpm dial to kPa/psi. The dial gauges, like Gavo said, assume more pressure = more flow, they are cheaper to make but not as accurate for flow as the floating ball type flowmeters.

For those thinking of getting a welding regulator - if it has a floating ball type flow meter make sure you do your research in to the specs for the model your looking at as some regulators have a fixed outlet pressure (between 20 and 50psi depending on make and model) that may not be adjustable. If the price is right and its output pressure is above what you want to put to the keg then a cheap mini compressed air regulator may make it usable. Remember to check the treads on the fittings as they can be different sizes and type - air fittings tend to be BSP, some regulators have NPT. bigger hardware shops have them in the compressed air fitting section (was relieved to find a NPT to BSP adapter for my reg in Bunnos for $2).