APCO Surge Check Valves (CSV)
The APCO Surge Check Valve is designed to prevent critical shock conditions occurring in installations where the operating conditions could cause a regular Air Vacuum Valve to slam open and/or closed. The Surge Check Valve is bolted to the inlet of an APCO AVV Air/Vacuum Valve to protect it from slam.
The Surge Check Valve may be purchased as a complete assembly, or purchased separately to add to a previously installed air/vacuum valve. Because the Air/Vacuum Valve and the Surge Check unit are each self-contained items, the Surge Check can be added to any Air/Vacuum Valve already in service, making it into a Slow Closing Air Vacuum Valve. CSV Surge Check Valves are available in sizes 1-18” (25-450mm)
The Surge Check Valve operates on the interphase between the kinetic energy in the relative velocity flows of air and water. The Surge Check Valve is a normally open valve, so that air passes through unrestricted. When water rushes into the Surge Check Valve, the disc begins to close and reduces the rate of flow of water into the air valve by means of openings in the disc. This ensures normal, gentle closing of the Air/Vacuum Valve regardless of the initial velocity flows and minimizes pressure surges when the valve closes.
As soon as the Air/Vacuum Valve is closed, the pressure on both sides of the Surge Check Valve disc equalizes and the disc automatically returns to its open position. The Air/Vacuum Valve does not need an incipient vacuum to open; it can open at any time the water level drops and the line pressure approaches atmospheric level. This immediately allows the full re-entry flow of air into the pipeline before a vacuum can form.
Where Should Surge Check Valves Be Used?
Because the pipeline media flows through the Surge Check Valve, it should be used in applications containing clean media. Following are locations where Surge Check Valves may be needed:
- High points in pipelines where the hydraulic gradient and flow conditions are such that a negative
- High points on sections of pipelines having water velocities in excess of 10 fps (3.048 m/s).
- Adjacent to any quick-closing valve in a pipeline such as a check or gate valve where a vacuum can be formed upon closure.
- On the discharge of a larger deep well turbine pump, between the pump and the check valve.
Surge Check Valves (CSV) Specifications
Additional sizes and materials available on application. Contact DeZURIK.