Lumberg said:
The Pressure Reducing Valve is an automatic control valve designed to reduce a higher inlet pressure to a lower constant outlet pressure regardless of fluctuating flow rates and/or varying inlet pressure.
It is a pilot controlled, hydraulically operated, diaphragm actuated globe valve in either the oblique (Y) or angle pattern design. Valve differential pressure powers the diaphragm actuator open or closed.
The lower control chamber is connected through a fixed orifice to the downstream pressure, which serves to cushion the closing of the valve.
The upper control chamber, which operates on a two-way control principle, has varying pressure produced by the regulating pilot and the pilot's internal upstream restriction needle valve.
The pressure regulating pilot senses downstream pressure and modulates open or closed. This varies the pressure in the upper control chamber causing the main valve to throttle thus maintaining constant delivery pressure.
When the downstream pressure falls below the pilot setting, the pilot opens, pressure in the upper control chamber decreases, and the main valve modulates open to increase downstream pressure and maintain pilot setting.
Should the downstream pressure rise above the pilot setting, the pilot closes, pressure in the upper chamber increases and the main valve throttles close to decrease downstream pressure to the pilot setting.
The Pressure Reducing pilot has an adjusting screw to preset the desired downstream pressure and an internal needle valve to control the closing speed.
For easy identification the pressure reducing pilot is stamped with the number "2" on the side of the pilot body .
Another note:
You may have debris built up in your pipes. That needs to be blown out!
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