Booster question

[Jimmer]

A random thought popped into my head just now. Do any of the single stage, single acting boosters use drive gas to cycle in both directions, or do they use the gas pressure from the supply bottle to cycle back?

Thanks,
Jim

 

[rjack321]

You kinda answered your own question... "Single Acting"
The drive gas is vented to the atmosphere and the supply gas (pressure) returns the piston to the starting position.

 

[Jimmer]

Fair enough, but to me, "single acting" means it only pumps gas in one direction, and has nothing to do with the drive section. Obviously double acting and two stage boosters are driven in both directions, so I am curious if the single piston (AG-30 for example) are driven both ways. It makes sense that they dont need to be driven back tho.

 

[dannobee]

A random thought popped into my head just now. Do any of the single stage, single acting boosters use drive gas to cycle in both directions, or do they use the gas pressure from the supply bottle to cycle back?

Thanks,
Jim

They use pilot valves to redirect drive gas to the other side of the piston. (Otherwise they would never cycle with ambient inlet, which they obviously do-it's one of the checks to determine proper outlet pressure)

 

[dannobee]

Oh, and Single Acting boosters have one high pressure gas barrel and piston. Double Action and Two Stage boosters have two high pressure gas barrels and pistons.

Double action boosters can also have two drive gas pistons. The AGD-32 is one of those boosters.

 

[Zodiacdiverdave]

Double acting means that it will compress the gas in both directions of the cycle, these boosters will have a piston on both sides of the barrel, single stage boosters will have 2 compression pistons that are the same size and volume and work in parallel. The advantage here is that the output volume is doubled. A two stage unit will have the second piston that is smaller in diameter, the gas is first pumped in the larger cylinder, compressed and then sent to the second cylinder where it is compressed even further thus working in series, the advantage here is higher pressures.
The large piston in the barrel uses LP gas to compress the high pressure gas by the machanical advantage of the larger surface area of the piston. When it reaches maximum stroke the piston makes contact with a pin which activates the cycling valve and dumps the LP gas from the barrel and then the piston is forced back back to the starting position where it makes contact with another pin and the process is repeated. The pilot valve is used to control maximum output pressure.
ZDD

 

[Jimmer]

Yep, I know all of that. Just wanted to know if single stage, single piston boosters use drive gas in both directions or just one. Just seemed to me that using it in both directions would be a waste of drive gas, but since I have never put my hands on a booster before, I figured I'd ask the experts.

Double acting means that it will compress the gas in both directions of the cycle, these boosters will have a piston on both sides of the barrel, single stage boosters will have 2 compression pistons that are the same size and volume and work in parallel. The advantage here is that the output volume is doubled. A two stage unit will have the second piston that is smaller in diameter, the gas is first pumped in the larger cylinder, compressed and then sent to the second cylinder where it is compressed even further thus working in series, the advantage here is higher pressures.
The large piston in the barrel uses LP gas to compress the high pressure gas by the machanical advantage of the larger surface area of the piston. When it reaches maximum stroke the piston makes contact with a pin which activates the cycling valve and dumps the LP gas from the barrel and then the piston is forced back back to the starting position where it makes contact with another pin and the process is repeated. The pilot valve is used to control maximum output pressure.
ZDD