757/757DCDA - In normal flowing operation, the independent Link-check remains closed until there is a water demand. Each check will then open and maintain an approximate 1 PSI differential in the direction of flow. In a nonflow or backflow condition, both checks will close until the resumption of normal flow.
957/957RPDA - In normal flowing operation the independent check valves will be open and the pressure differential relief valve located between the two check valves, the area called the zone, will automatically open and close to maintain the zone pressure at least 2 PSI lower than the inlet pressure. If demand for flow stops, the differential pressure relief valve will automatically open and discharge water to maintain the zone at a pressure of 2 PSI lower than the inlet pressure. After the pressure differential is reestablished, the differential pressure relief valve will automatically close.
Specifications - 757/757DCDA
The Double Check Valve Assembly shall consist of two independent torsion spring check modules within a single housing with sleeve access, required test cocks and drip tight shut-off valves. Torsion spring checks may be removed and reinstalled in housing without any special tools. The housing shall be constructed of 300 Series stainless steel with groove end connections. Torsion spring checks shall have reversible elastomer discs and in operation shall produce drip tight closure against reverse flow caused by backpressure or backsiphonage. Assembly shall be a Watts Regulator Company 757 or 757DCDA.
Specifications - 957/957RPDA
The Reduced Pressure Zone Assembly shall consist of two independent torsion spring check modules, a differentialpressure relief valve located between and below the two modules, drip tight inlet and outlet shutoff valves, and required test cocks. Both torsion spring check modules shall be contained within a sleeve housing constructed from 300 series stainless steel. Torsion spring checks shall have reversible elastomer discs and in operation shall produce drip tight closure against reverse flow caused by backpressure or backsiphonage. Assembly shall be a Watts Regulator Company 957 or 957RPDA.
|Rated Working Pressure 175 PSI||Rated Working Pressure : 175 PSI|
|Hydrostatic Test Pressure : 350 PSI||Hydrostatic Test Pressure : 350 PSI|
|Temperature Range : 33 F - 110 F||Temperature Range : 33 F - 110 F|
|Body Construction : 300 Series Stainless Steel||Body Construction : 300 Series Stainless Steel|
|End Connection : Groove per AWWA C-606 (IPS) or Flange per ANSI B16.1, Class 125||End Connection : Groove per AWWA C-606 (IPS) or Flange per ANSI B16.1, Class 125|
|757/957 Series Specification Sheets||Download|
|957 RPDA/957N RPDA/957Z RPDA|
|757/957 Series Installation Sheets|
Features of the SilverEagle Series
- 70% lighter than traditional designs
- Most compact design in the industry
- Entire valve body and quick access sleeve manufactured from 300 Series Stainless Steel
- Approved with gate valves or UL/FM butterfly valves
- Approved for horizontal, vertical or "N" patterns, 957 also available in "Z" pattern
- Utilizes groove connections for ease of installation & pipe alignment
- Patented Link-check assemblies allow ease of serviceability
- Replacable check disc rubber
- Smallest Enclosure