This is a direct-acting pressure-reducing valve with an adjustable spring operating against a flexible elastomeric diaphragm subjected to the reduced outlet pressure of the valve.
This valve is used for medium to low flow applications. See flow data below. For larger capacities refer to model PRS-09-FLG with offset flanges. Corresponding threaded NPT models are also available.
This valve can be used for water, air, gases, chemicals, solvents, and fluids including steam, depending on the materials selected (consult factory). Only clean, filtered, or strained liquids and gases should be used for best operation of the valve. A strainer or filter, depending on the degree of contamination, should be installed before the inlet of the valve. Strainers or filters can be purchased from Stra-Val to provide some degree of protection.
Features & Benefits
- Pressure-containing parts made from solid bar stock materials — unlike castings which have wall thickness variations.
- Body and flanges: Standard material is type 316 stainless steel. Special alloys (e.g. Monel, titanium, and Hastelloy) also available.
- Trim: Stainless steel for main valve and seat is standard. Teflon sealing option is also available for air or gas service.
- Teflon-Viton composite reinforced diaphragm is rated pressure of 100 PSI and minimum burst pressure of 300 PSI. Teflon film on the wetted side provides good corrosion resistance to a wide range of fluids and gases including steam. Viton is the elastomeric backing on the non-wetted side and is rated to 350 °F for most applications. Buna backing is available for lower temperatures.
- In-line flanges: 150 ANSI RF standard for this model with face-to-face dimensions as illustrated. Custom flange facing can also be made available. Bolt holes straddle centerline. Standard inlet flanges and outlet flanges are equal in size. Unequal flange combinations (larger outlet than inlet) are also available to compensate for expansion of gases at reduced pressures.