Aviation High Level Shut-Off Valve type 129-26 | Cla-Val

Cla-Val 129-26 High-Level Shut-Off Valve

The Cla-Val 129-26 is a hydraulically operated diaphragm valve designed for automatic high-level shut-off in fuel storage tank fill lines, both aboveground and underground. It is primarily used in aviation fuel storage systems where mechanical shut-off is required when the tank reaches a predetermined level.

Operating Principle

The valve is controlled by a CFM2 float pilot and operates using line pressure. When pressure is applied to the diaphragm chamber, the main valve closes tightly. When pressure is vented to a lower pressure zone, the valve opens. In the event of diaphragm failure, the valve defaults to the closed position, providing a fail-safe shut-off. Position indicator X101 is supplied as standard.

Construction and Connections

• Body type: Globe or angle pattern
• Sizes: Globe 1½”–16”, Angle 2”–16”
• Connection: ANSI flanged
• Pressure classes: 150, 250, 300 lbs
• Maximum pressure: up to 400 psi, depending on class/material
• Temperature range for light petroleum products: -40 to +140 °F
• Elastomers: Buna-N or Viton

Body Materials

Available body materials:

• Cast Aluminum 356-T6
• Cast Bronze ASTM B62
• Ductile Iron ASTM A536
• Cast Stainless Steel 303
• Cast Steel ASTM A216 WCB

Trim available in Bronze ASTM B61 or Stainless Steel 303. Material selection is based on fuel type, operating pressure, installation environment, and corrosion requirements.

Optional Control Accessories

Optional equipment includes X46A strainer, CK2 isolation valves, CV opening/closing speed controls, 81-01 check valve, quick connect assembly, and 55F thermal relief control. X105L switch assembly is available for electrical position indication to control or alarm systems.

Applications

• Filling of Jet A-1 or other light petroleum product tanks
• Airport fuel farms
• Fuel receipt lines requiring independent high-level shut-off
• Aboveground and underground storage tanks

FAQ

What data is required for valve selection?
Size, body type, pressure class, temperature, fuel type, static and dynamic line pressure, pilot operating pressure, body/trim material, and flange type.

Can maintenance be performed without removing the valve from the line?
Yes. The design allows for servicing without removing the valve from the piping.