Problem of air pressure regulator with enormous turn-down

[DAlbertson]

I'm building a test jig that needs an air pressure regulator with a very large turn-down:
Inlet pressure range = 80 to 120 psig
Discharge pressure range = 1 to 130 inches of water (0.036 to 4.7 psig)
Discharge flow rate demand = 0 to 150 CFM, with the maximum d(flow)/dt = 800 CFM/s

I've sent an RFQ to a specialist company that manufactures electrically actuated regulators. They did not bid, saying that they did not feel they could reach the low end of the discharge pressure spec (1 inch of water). They were willing to specify 5 inches of water, but unfortunately that is too high for my application.

The worst-case turn-down for this regulator is about 4000:1. Not exactly a pretty sight. But I am pretty flexible on how the regulation is accomplished: multi-stage regulators, intermediate accumulators, no piping size constraints...whatever.

Does anyone have an idea as to how I should proceed here?

Thank you very much!
Dave

 

[SNORGY]

Look into Fisher Y692 or Itron B34 / B38 style valves.

 

[Latexman]

Look at the Emerson/Fisher/Appalachian Controls 95 series (ACE95).

http://www.documentation.emersonprocess.com/groups/public/documents/bulletins/d102720x012.pdf

Good luck,
Latexman

Technically, the glass is always full - 1/2 air and 1/2 water.