A rubber disc check valve is a valve device that automatically opens and closes based on the flow of the medium itself. Its core function is to ensure unidirectional flow of the medium in the pipeline. When the fluid flows in the forward direction, the medium pressure acts on the rubber sealing surface of the valve disc, overcoming the valve disc's own weight and possible spring resistance, causing the valve disc to open and forming a smooth flow path. During this process, the 45° upward angle design of the valve disc enables rapid response and significantly reduces fluid resistance loss.
When the medium stops flowing or a reverse flow trend occurs, the valve disc undergoes a crucial closing process. At this time, the fluid kinetic energy gradually weakens, and the valve disc begins to fall back under the combined action of its own weight, spring force (if configured), and reverse fluid pressure. The rubber sealing surface forms a tight seal with the valve seat, completely blocking the backflow of the medium. It is particularly noteworthy that the elastic properties of the rubber material allow the valve disc to adapt to a certain degree of deformation, thereby compensating for gaps caused by manufacturing tolerances and wear, ensuring sealing reliability during long-term use.
Water hammer effect is an operating condition that requires special attention for this type of valve. When the pump suddenly stops, the inertia of the fluid in the pipeline causes a sharp fluctuation in pressure. Rubber flap check valves achieve rapid yet abrupt closing characteristics through optimized valve flap quality and structural design, keeping water hammer pressure within the system's tolerance range. Some high-end models are also equipped with a buffer mechanism, using hydraulic damping principles to further smooth the closing process.
Structural Components
Rubber Flange Check Valve Body: Made of ductile iron, stainless steel, or plastic (such as PVC/CPVC), designed with a straight-through or right-angle flow path and a smooth inner wall to reduce fluid resistance.
Rubber Flange (Valve Core): The core functional component, made of elastic rubber (such as NBR or EPDM), in shapes including disc, duckbill, or multi-flange. It opens and closes based on its own elasticity and the pressure of the medium.
Valve Seat: Seals in conjunction with the rubber flap, typically made of stainless steel, with a high-precision machined sealing surface to ensure a tight fit.
Spring (Optional): Some models are equipped with a stainless steel spring to assist in the rapid closing of the rubber flap, especially preventing delayed closure under low flow conditions.
Seal: A sealing ring (such as an NBR ring) is installed at the connection between the valve body and the pipeline to prevent medium leakage.
Forward Flow: The medium pressure pushes open the rubber flap, opening the flow path.
Reverse Flow: The rubber flap, under its own elasticity and the reverse medium pressure, presses tightly against the valve seat, preventing backflow. Water Hammer Suppression: The 45° upward-angle valve design or duckbill-shaped structure shortens the closing time and reduces the impact of water hammer on the pipeline.
Applications of Rubber Disc Check Valve:
Water Supply and Drainage Engineering
Installed at the outlet of water pumps to prevent backflow and water hammer damage to the pump.
Configured on the bypass pipes of the inlet and outlet pipes of water storage tanks to prevent backflow of tank water into the water supply system.
Petrochemical Industry
Suitable for operating conditions with pressures of 1.0-4MPa and temperatures of -29℃ to +80℃, for conveying media such as clean water and oil.
Highly corrosion resistant, capable of handling acid and alkaline solutions and high-viscosity media (such as mud and crude oil).
Rubber Disc Check Valve Factory
