Hydraulic Rate of Flow & Pressure Sustaining Valve - 40-25 & 640-25 | Cla-Val

Cla-Val 40-25 / 640-25 – Flow Control & Upstream Pressure Sustaining Valve

The Cla-Val 40-25 / 640-25 is a hydraulically operated, diaphragm-actuated, pilot-controlled valve designed for applications requiring downstream flow limitation while maintaining upstream supply pressure above a preset threshold.

Control Function

This valve integrates two control modes:

• Flow regulation via differential pressure across an X52E orifice plate.
• Pressure sustaining using a CRL/CRL60 pilot, which modulates in response to upstream pressure fluctuations.

If downstream flow exceeds the setpoint, the main valve throttles. Should upstream pressure approach the setpoint, the pressure sustaining pilot further restricts valve opening to prevent supply pressure drop.

Typical Applications

• District water supply zones with controlled flow rates.
• Main pipeline protection against pressure drops.
• Industrial process water distribution networks.
• Tank filling lines requiring regulated flow.
• Systems where downstream demand must not destabilize upstream networks.

Construction / Options

• 40-25: Full internal port, base valve 100-01.
• 640-25: Reduced internal port, base valve 100-20.
• Body: Ductile iron ASTM A536, cast steel ASTM A216-WCB, or bronze UNS 87850.
• Flanges: ANSI B16.42, B16.5, or B16.24, Class 150 and 300.
• Disc and diaphragm: Buna-N, reinforced diaphragm.
• Stem, nut, spring: Stainless steel.
• Water temperature: up to 180°F (approx. 82°C).

Optional Accessories

Available options include pilot line strainer, isolation valves, position indicator, pressure gauge, adjustable opening/closing speed, and check feature to prevent reverse flow.