Disc check valves

Marine disc check valves are used to prevent reverse flow in pump discharge lines, cooling water systems, auxiliary water circuits, and piping networks where closing speed affects hydraulic shock. Operation is based on a pivoting disc that opens under forward flow and returns toward the seat as flow rate decreases or reverses.

This category includes the Cla-Val Series 586 pivoting disc check valve, with ANSI flanged ends, a ductile iron body, and available pressure classes of 125, 150, 250, and 300 lb. The two-piece body design provides an enlarged flow area at the seat section, replaceable seat and disc rings, metal-to-metal shutoff, and body inspection openings for maintenance access.

The valve is available in 586CT configuration with a top-mounted control arrangement for slow opening and controlled closing, and in 586CB configuration with a bottom-mounted buffer arrangement for free opening and controlled final-stage closing. These variants are evaluated in pump service where slam reduction, pressure surge control, and adjustment of closing time to actual system conditions are required.

Published construction data lists body material as ductile iron ASTM A536 65-45-12, disc material as bronze alloy C90700 for sizes 3 in. to 10 in. and ductile iron for 12 in. to 14 in., seat and disc rings in bronze ASTM B16 C36000, and hinge pins in stainless steel ASTM A582 Type 303. Selection should consider ANSI pressure class, design flow rate, available differential pressure, allowable head loss, installation orientation, access for inspection, and material compatibility with the service fluid. For pump-system duty, review closure characteristics, surge behavior, leakage expectations for metal seating, and maintenance requirements for seat ring and hinge components.