Valve Terminology

These terms are largely synomymous. A pressure regulator can be configured to control the upstream pressure, the downstream pressure, or the difference between the two pressures. "Reducing valve" more commonly refers to a downstream pressure regulator.

You are right of course, but I would add that a valve that controls upstream pressure is usually called a back-pressure valve and all three terms distinguish this type of valve from a control valve.

Drew

And a PRV or Pressure Regulating Valve accepts a variable input, below it's max design pressure, and delivers a regulated constant set output.

All responses good. My two cent's.....This is also the point when these various types of valves design should be noted, because there is generally a seat/trim design that relates to the valves function, such as where the process flow enters the valve body - under the seat or on top of the seat, various trim designs,or which side of a diaphragm flow is sensed, etc.

A pressure regulating valve modulates the pressure to a fixed value as does a pressure regulator.

A reducing valve put simply would be like taking your hose to wash your car, turning the water on and cracking the nozzle to a trickle on the end creating a "reducing valve"

By doing this you have effectivley "reduced" the pressure but still have flow.

Its early (0530) here and I have had no coffee yet, my apologies if this doesn't make complete sense, it does to me...LOL