Check valves are essential in wastewater treatment. They are used in lift stations for preventing reverse flow when the pumps are not in operation. There are as many types of check valves as pumps, so it is important to understand the essential characteristics that affect performance in wastewater service. Dervos’ swing check valve is produced in accordance with American Water Works Association (AWWA) C508. The valves are made of iron with corrosion-resistant internal mechanisms. Swing check valves use a 90-degree seat and are typically provided with a lever and weight to assist with closure and provide position indication. The valves also can be equipped with springs, air cushions or oil dashpot arrangements to reduce the valve’s propensity to slam.
A variation of the traditional swing check is the resilient hinge design, which has a much shorter disc stroke that can greatly reduce the slamming problems, especially for higher head applications. Additional benefits of the resilient hinge design include a corrosion-resistant disc, an encapsulated hinge pin, the option for position indication and a top access cover for ease of maintenance.
