Natural Gas Pressure (Self-contained) Regulator Chatter
Natural Gas Pressure (Self-contained) Regulator Chatter
(OP)
Hello all,
I am designing a natural gas pressure reducing valve system which is utilizing self-contained pressure regulators to reduce the pressure of incoming gas. The flows through the system are such that I cannot size a single regulator to control over the full range of flow (the turndown is greater than 100:1). So, I must design both a "High-flow" and "Low-flow" pressure reducing train and install them in parallel.
I believe this is commonly accomplished, however, my question is this: During cases of low flow, what will keep the larger, "High-flow" valves from chattering and trying to control pressure when the "Low-flow" valves should be operating and controlling pressure.
I believe this can be done by setting the “Low-flow” valves to a control to a higher pressure (say 130 psig) and set the “High-flow” valves to a slightly lower pressure (say 125 psig). This way, during periods of low flow, the “High-flow” valves will be closed since the “Low-flow” valves will be controlling to a higher pressure downstream. Once the system demands more flow, the pressure will drop and the “High-flow” valves will open.
Any thoughts or previous experience is always appreciated.
Regards,
GHB
I am designing a natural gas pressure reducing valve system which is utilizing self-contained pressure regulators to reduce the pressure of incoming gas. The flows through the system are such that I cannot size a single regulator to control over the full range of flow (the turndown is greater than 100:1). So, I must design both a "High-flow" and "Low-flow" pressure reducing train and install them in parallel.
I believe this is commonly accomplished, however, my question is this: During cases of low flow, what will keep the larger, "High-flow" valves from chattering and trying to control pressure when the "Low-flow" valves should be operating and controlling pressure.
I believe this can be done by setting the “Low-flow” valves to a control to a higher pressure (say 130 psig) and set the “High-flow” valves to a slightly lower pressure (say 125 psig). This way, during periods of low flow, the “High-flow” valves will be closed since the “Low-flow” valves will be controlling to a higher pressure downstream. Once the system demands more flow, the pressure will drop and the “High-flow” valves will open.
Any thoughts or previous experience is always appreciated.
Regards,
GHB





RE: Natural Gas Pressure (Self-contained) Regulator Chatter
the lower flow regulator should have the higher pressure setpoint than the high-flow regulator as you so describe. the difference in setpoints may need be verified/tested, but 5-7-psi is adequate for similar systems i'm aware of.
good luck!
-pmover
RE: Natural Gas Pressure (Self-contained) Regulator Chatter