Swing Check Valves

A swing check valve has a disc mounted on a hinge or shaft that swings. When forward flow is allowed, the disc swings off the seat, and when flow is stopped, the disc swings back onto the seat, blocking reverse flow. The valve's shut-off characteristics are influenced by the weight of the disc and the return flow.

To achieve optimum performance, a lever and weight or a lever and spring are frequently mounted. Swing check valves with a lever and weight are suitable for installations where water hammer is a concern at standard velocities. Swing check valves with an external spring and a lever are ideal for high pressure, minimal back pressure, and high flow rates.

When installing a swing check valve, it's crucial to remember that it's not fully maintenance-free because the disc needs to be cleaned every now and again. In addition, a lever is frequently installed to allow for visual inspection. As a result, swing check valves are frequently fitted in areas where people are present.

AVK manufactures swing check valves that can be maintained easily. The bonnet assembly, including the hinge and disc, can be removed from the body and maintained by unscrewing a few bolts.

When mounted with weight and lever, the swing check valves in small dimensions allow for priming with the manual movement of the lever. The weight on the lever can be adjusted to provide a soft closure on the seat as well as the best closing speed to avoid water hammer. As an added precaution, a guard covering the lever and weight is offered, which removes the possibility of injury. Limit switches for remote monitoring are available with the guard.

Main features summary for AVK swing check valves

  • Bonnet/disc design gives easy access to maintenance 
  • Disc with steel insert is fully vulcanized with EPDM rubber (up to DN 300) ensuring optimum sealing ability 
  • Lip sealing on the disc ensures tightness 
  • Light-weight disc requires a minimum of force to open and close the valve 
  • The disc is able to move slightly both horizontally and vertically to close completely tight 
  • Hinge tightened around the shaft with bolts to eliminate play and thus ensure durability 
  • Full bore ensures low head loss 
  • Ductile iron with epoxy coating in compliance with DIN 3476 part 1 and EN 14901