Dual plate check valves can be used in pipelines to prevent the backflow of a liquid or gaseous media. Similar to the intermediate flange non-return valve, the dual plate check valve is flanged into the pipeline system. It opens its plates only in one direction. Once the pressure of the medium flowing in the chosen direction exceeds the spring pressure of the plates and the valve resistance, the two semicircular plates open and allow the medium to flow through. As the pressure drops, or if the medium changes its flow direction, the plates close reliably. Since the plates open parallel to the flow direction, the dual plate check valves have a very low resistance and allow you to realize exceptionally high flow rates (KVS). It is mandatory to ensure that no contaminated medium flows through the plates. Contaminations could block the plates or damage the seals, which are permanently vulcanized, which can result in leaks.