APCO Slanting Disc Check Valves (CSD)

With decades of experience to guarantee reliability and outstanding performance, APCO CSD Slanting Disk Check Valves are ruggedly designed with superior flow characteristics, minimal head loss and maximum slam resistance. Slanting disc check valves are the most reliable and efficient check valves available. They are ideally suited for clean municipal/industrial water and other industrial liquid applications.

Because of its unique two-piece body design and slanted disc orientation, the APCO Slanting Disc Check Valve has superior flow characteristics (lowest head loss) when compared to other check valve designs. The angled body seat allows for a 40% expanded cross sectional flow area, so the area occupied by the mass of the disc is more than compensated for by the expanded flow area. Each body half has an o-ring seal and valves sizes 6″ (150mm) and larger have an access cover for internal inspection on each body half.

The airfoil design of the disc, like the wing on an airplane, offers minimal resistance to flow while lifting and stabilizing in the full open position. Flow characteristics are further improved because the long laying length of the valve body allows water to smoothly enter and pass through without turbulence, eddies or cavitation.

The unbalanced disc weight (heavier below the pivot point) causes the slanting disc to free fall into shut-off position with minimal reverse flow and open with a slight pressure differential. This results in excellent slam resistance combined with lowest head loss.

APCO CSD Slanting Disc Check Valves close with precise clearance around pivot pins, ensuring self-centering, 360° seating between the concentric disc and body seat rings. These rings are precisely machined and move together or apart with minimum interference, thus eliminating wearing and leakage for many years of service. This movement allows tight seating to meet AWWA C508 standard for metal-to-metal seated valves and virtually eliminates seat maintenance and replacement.