Please can someone explain the basic operation of a pressure regulator valve in a pneumatic system.?

Question

Please can someone explain the basic operation of a pressure regulator valve in a pneumatic system.?

Answer 1

Yeow. You sure got more than a "basic" understanding now huh? "Basically", pressure regulator valves in aircraft pneumatic systems are of the butterfly type. Simply a gate that pivots on a shaft inside the duct. An electric motor typically operates the movement.

Answer 2

As the name signifies, the job of a pressure regulator valve is to regulate the pneumatic pressure in  a system. The valve merely maintains the pressure at which it is set. A sensor within the system feeds a signal to the valve which then mechanically opens or closes to adjust the pneumatic pressure within the desired range. The valve is actuated either mechanicaly or via a solenoid which may be electrical or hydraulically operated.

Answer 3

Hopefully, this will help.

http://www.plastomatic.com/pr101.pps

I hate to disagree with John, but butterfly valves are control valves, not regulators. A separate regulator might be used to control the butterfly valve.

Of course, this is all semantics...

Answer 4

The engine has two bleed ports for pneumatic use: 1 from low stage compressor (9th stage) and the other from the high stage compressor(14th stage). At idle and low engine throttle lever setting the bleed from the low stage is not sufficient to supply the demands of aircraft users so 14th stage will open and supplies as high as 70psi-110psi. the high pressure from the 14th stage closes the 9th stage bleed port. This is the time the pressure regulator functions, it see to it that pressure is regulated to 23-48psi as working pressure for pneumatics, pack flow valve (for aircon).

Add'l tip: when you see a pilot flight remarks which say "split duct pressure (most pressure gauges are dual for 2 engines) LH needle at 23 while RH needle at 60." Chk first the log book which phase of the flight it occured. Ex. at cruise then low stage bleed supplies so  Rh press.reg.valve is at fault perhaps the butterfly valve doen't modulate to a more close position.