This is a direct-acting diaphragm pressure-reducing valve (most often referred to as a pressure regulator) with an adjustable spring operating against a flexible elastomeric diaphragm subjected to the reduced outlet pressure of the valve which is controlled through an internal sensing port. This makes the valve an accurate pressure-sensing valve, or pressure control valve used to control outlet pressures with a wide range of inlet pressures.
Unlike unbalanced diaphragm pressure-reducing valves, this pressure valve is a balanced inlet design and will work quite well on applications where the inlet pressure will fluctuate widely and will have little effect on outlet pressure. The valve will operate in a vertical orientation as illustrated, horizontal, or any other orientation.
This valve is designed for use with corrosive liquids, depending on the materials selected. See material display notes in pricing section to help select materials
When this pressure reducing valve is selected, it is always recommended that a relief valve be installed on the downstream side of the valve to protect the diaphragm and other equipment downstream of the valve in case of excessive pressure buildup. This is especially necessary when high inlet pressures are present. Therefore, do not attempt to use this as a shutoff valve. For prolonged or even momentary periods of shutoff, install separate shutoff or isolation valves to keep the relief valve from tripping. The standard construction for this pressure-reducing valve is with a soft seat which will provide class ANSI VI (Bubble tight) seal.
This in-line pressure regulator has fairly adequate Cv values for most applications. See below.
Select the valve size, spring range, material options in the customized pricing and ordering section indicated by the red arrows. You have the ability to customize your valve choices by selecting the wetted materials, and choice of seat materials to suit your requirements. The standard nonwetted materials are PVC and Stainless steel as indicated in the Material List. Once your selections are made a price quote can be generated and printed directly to your computer or immediately e-mailed to you. Or you may proceed to "Order and Checkout" to order online.
The valve operates on the principle of balancing the spring force that is set by the user against the outlet pressure acting under the diaphragm. There is an internal pressure balancing port that subjects the outlet pressure directly to the underside of the diaphragm. When the outlet pressure falls below the set pressure required by the system on the outlet side of the valve, the spring force overcomes the force balance under the diaphragm causing the poppet and diaphragm assembly to drop down causing the valve to open and allow higher pressure at the valve inlet to pass through the valve. When the pressure rises to a sufficient level to restore the force balance against the spring, the valve will move toward the closed position. The valve is completely self-regulating and the poppet is constantly moving to respond to pressure changes on the outlet side of the valve, not the inlet. The only time the poppet closes completely is when the outlet pressure has been reached to its set point. As long as the valve is able to shut off properly without solids or other material build up in the seat or because of seat wear, the valve should be able to maintain and hold the outlet pressure and keep it from rising for brief periods of time. If the valve is set with no flow passing through the system, there will be some drop (drop in outlet pressure) caused by relaxation of the spring when the valve first has to open. This occurs with all direct spring operated valves and can be compensated by making a slight readjustment to the set pressure once the desired capacity has been achieved.