Check Valve - 81-01 & 681-01 | Cla-Val

Cla-Val 81-01 / 681-01 Check Valve

The Cla-Val 81-01 / 681-01 is a hydraulically operated, no-slam check valve designed for water distribution systems. The valve opens when inlet pressure exceeds outlet pressure and closes tightly upon pressure reversal, minimizing hydraulic shock.

Operation

Downstream pressure is routed to the cover chamber via control tubing, enabling controlled closure. Gradual opening reduces surge effects. The Buna-N resilient disc ensures tight shutoff, even in the presence of minor particulates in the water.

Technical Data

• Type: Hydraulically operated no-slam check valve
• Models: 81-01 (globe), 681-01 (angle)
• Body: Ductile iron, ASTM A216 WCB, or bronze
• Connection: ANSI flanged
• Pressure Classes: 150 lbs, 300 lbs
• Water temperature: up to 82°C
• Disc: Buna-N
• Diaphragm: Nylon-reinforced Buna-N
• Stem, nut, spring: Stainless steel

Applications

Suitable for pump discharge (booster pumps), waterworks pump stations, industrial water networks, and lines requiring unidirectional flow with slam mitigation.

Selection Criteria

Valve sizing should be based on flow rate, pipeline velocity, pressure class, globe or angle configuration, and installation location. For velocities above 1.8 m/s, surge analysis and consideration of surge control valves are recommended.

FAQ

Is this a simple mechanical check valve?
No. Closure is hydraulically actuated via a control chamber.

When is it used?
Applied on pumps where reverse flow may cause slam or water hammer.

Are control accessories available?
Yes, options include X141 pressure gauge and X101 position indicator.