Aviation Hydrant Pit Valve type 352GF | Cla-Val

Cla-Val 352GF Hydrant Pit Valve

The Cla-Val 352GF is a below-ground hydrant pit valve designed for aircraft refueling systems. It is a pilot-operated, piston-type on/off valve, typically installed at the end of an underground fuel line, upstream of a 4” API hydrant pit coupler. The valve serves as the final shutoff device in accordance with NFPA 30 requirements.

Deadman Operation

The 352GF can be specified with the following pilot actuation options:

• manual deadman pilot
• pneumatic deadman pilot
• pneumatic pilot with defuel function
• pneumatic pilot with emergency air release lanyard

For pneumatic versions, the optional emergency air release enables manual closure even if air pressure remains in the deadman circuit.

Hydraulic and Mechanical Data

• Compliance: EI Specification 1584 Fourth Edition
• Operating temperature: -40 to +180 °F / -40 to +80 °C
• Design pressure: 275 psi
• Operating pressure: -1.5 to 200 psi
• Opening to 90% flow: 5–10 s
• Closure time from 1189 gpm / 4500 l/min: 3–5 s
• Pressure drop at 1189 gpm: 23.5 psi
• Fits 13” diameter pits

Construction Materials

Lower body: ductile iron ASTM A536 65-45-12. Upper API adapter: stainless steel Grade 410, Brinell 345/365. Piston: stainless steel. Seals: nitrile and fluorocarbon. Corrosion protection: electroless nickel plating per MIL-C-26047. No aluminum is used in pressure-containing components, supporting durability in fuel, moisture, and high mechanical load environments.

Ordering Options

• 4: 4” ANSI 150 inlet flange
• 6: 6” ANSI 150 inlet flange
• A: air/fuel pilot
• AD: air pilot with defuel
• M: manual pilot
• AL: air pilot with override
• S4/S6: stone guard
• I: 20 mesh strainer for 4” and 6”

Maintenance

The integrated servicing valve allows pilot removal for maintenance without depressurizing the delivery system, minimizing intervention on buried piping and reducing pit downtime.

FAQ

Compatible couplers:
4” API hydrant pit couplers, e.g., Cla-Val 351GF-15 and 353GF pressure control coupler.

When to specify emergency air release?
Required when independent closure of the pit valve is needed in pneumatic deadman systems, regardless of air supply status.