Wafer Check Valve

• The KOSEN series dual plate check valves feature a short face-to-face dimension and a dual-plate design. End connection options include wafer type, lug type, and double-flange type.
• These valves are available in sizes from 2 Inches to 60 Inches, with pressure ratings ranging from ASME Class 150 through 2500 LB. A wide range of body and trim materials is also available upon customer request.
• Compared with conventional swing check valves, KOSEN dual plate check valves offer several advantages, including zero external leakage due to the absence of bolted or threaded body connections, cost savings, and installation flexibility in any pipeline orientation. They also provide superior sealing performance, minimal line shock, lower pressure loss, and zero seat wear.
• This series of valves is widely used in oil and gas production, petroleum refining, petrochemical processing, pulp and paper industries, shipbuilding, and other applications requiring reliable prevention of fluid backflow.

» Retainerless Body Design (Patent Protected): KOSEN dual plate check valve bodies feature a one-piece, short-cylinder design without holes through the body wall. This eliminates the need for external pins or plugs and prevents external leakage. For critical service applications involving hazardous or toxic media, this design is an excellent choice for minimizing unwanted atmospheric leakage.

» Body Slot Design for Hinge Pin Fitment: A disc slot with carefully calculated clearance is designed to fit the hinge pin and allow movement only in the direction of flow. This design eliminates the possibility of friction caused by the heel of the dual plate during operation.

» Shock Bumpers: Integral cast bumpers on the back of the dual plates effectively prevent repeated impact and reduce the force exerted by the dual plates against the stop pin when the valve is fully open. This extends valve service life and minimizes maintenance costs.

» Two Independent Torsion Springs: Two high-torsion springs ensure rapid valve closure and reduce water hammer effects, thereby extending valve life and improving overall system performance.

» Uninterrupted Gasket Sealing Surface: The KOSEN dual plate design incorporates an internal retention fitting that does not interfere with the gasket sealing surface, ensuring an effective seal between the valve and the pipeline.

» Lightweight and Compact Wafer Design: The dual plate wafer design makes the valve significantly lighter, typically only 10–25% of the weight of a conventional swing check valve. This reduces initial valve costs and lowers installation expenses.

» Flexible Installation Position: The spring-assisted closure feature, combined with the lightweight structure that minimizes pipeline bending loads, allows the valve to be installed in any position. This provides greater flexibility for designing efficient and cost-effective piping layouts.

» Dual Plate and Flat Seat Design: When the valve opens, the heel of the dual plate lifts in the direction of flow, preventing the heel from dragging across the seating surface and causing wear. During valve closure, the two high-torsion springs and back pressure force both the disc toe and heel back onto the flat seat in sequence to achieve reliable sealing.

» Wide Size Range: Due to the lightweight wafer design, compact installation space, spring-assisted operation, and effective sealing performance, these valves are suitable for large-diameter piping systems, including sizes up to 60" and above.