Gate Valve - Cryogenic | Neway

Neway Cryogenic Gate Valve

The Neway cryogenic gate valve is utilized for flow isolation in LNG, liquid nitrogen, liquid oxygen, argon, and other low-temperature industrial gas lines. Its operation is on/off; it is not used for throttling as a partially open position increases wear on seats and wedge.

Operating Range

• Pressure rating: ASME Class 150–2500 / PN16–PN250
• Ends: RF, RTJ, BW
• Body material: stainless steel
• Actuation: manual, pneumatic, electric, or hydraulic
• Cryogenic gate valve series in technical brochure: 2"–42", Class 150–2500, temperature -196 to 400 °C

Cryogenic Design

The valve features an extended bonnet / extended stuffing box to keep the packing outside the extremely cold zone. This reduces the risk of freezing and maintains more stable sealing behavior at the stem. The technical brochure also mentions a PCTFE sleeve on the stem, welded seats, and Stellite hard facing on sealing surfaces.

Materials and Standards

For temperatures -110 to -196 °C, materials such as CF3M, CF3, CF8M, CF8, F316L, F304L, F316, F304 and dual certified versions are recommended. The bonnet extension meets BS 6364 and SPE 77/200 requirements, while documentation mentions ASME B16.34, related API/ASME/ISO standards, and MDMT per ASME B31.3.

Selection Points

• Fluid type: LNG, LIN, LOX, or other cryogenic medium
• Minimum design metal temperature
• RF/RTJ/BW connection
• Relief hole or self-relief seat to avoid overpressure in the cavity
• Low emission packing requirement per ISO 15848 / SHELL 77/312

FAQ

Why is an extended bonnet required?
To keep the packing at a higher temperature than the line.

When is cavity relief needed?
In cryogenic liquids, as trapped liquid can increase pressure upon warming.

Is it suitable for oxygen service?
Only with confirmation of cleaning, materials, and procedures for oxygen use.