1. Size Range:

Typically available in sizes ranging from 1/4" to 24" (DN 6 to DN 600) or larger depending on the application.

2. Pressure Ratings:

• Cryogenic valves are available in pressure classes from 150# to 1500# (PN 10 to PN 100).

• Pressure ranges typically cover up to 50 bar (725 psi) but can vary based on the valve type and material.

3. Temperature Range:

Cryogenic valves are capable of functioning at extremely low temperatures, typically from -196°C (-320°F) up to ambient temperatures. They are designed to perform in temperatures as low as -269°C (for applications like liquid helium).

4. Material Specifications:

Body Materials:

• Stainless Steel: 304, 316, 316L (common due to excellent low-temperature properties)

• Carbon Steel: Often with austenitic stainless steel internals for strength and cryogenic stability

• Bronze and Brass: For lower-pressure and non-corrosive applications

• Monel, Inconel, Hastelloy: For highly corrosive cryogenic media

Seating Materials:

PTFE (Teflon), PCTFE (Kel-F), or other soft seat materials suitable for cryogenic conditions to ensure bubble-tight sealing.

5. Valve Types:

• Globe Valves: For precise control of flow in cryogenic systems.

• Ball Valves: Often used for quick on/off control in cryogenic systems.

• Gate Valves: Typically used for isolation in larger cryogenic systems.

• Check Valves: Ensures unidirectional flow in cryogenic pipelines.

• Butterfly Valves: Used in larger cryogenic applications for flow control.

• Needle Valves: For fine-tuned control in cryogenic instrumentation systems.

6. Design Features:

• Extended Bonnet: Most cryogenic valves feature an extended bonnet to ensure that the stem packing stays well above the cold zone, preventing freezing and ensuring the integrity of the seal.

• Low Emission Sealing: Ensures that emissions are minimized, meeting strict environmental regulations like ISO 15848.

• Double Sealing System: A secondary seal is often incorporated to ensure safety in case of failure of the primary sealing system.

• Fire-Safe Design: Fire-safe cryogenic valves are designed to contain pressure and prevent leakage during fire exposure.

• Anti-static Device: For ball valves, especially those used in cryogenic services, to prevent static electricity buildup.

7. End Connections:

• Butt Weld Ends: Common in high-pressure cryogenic systems to avoid leakage.

• Socket Weld Ends

• Flanged Ends: ASME, ANSI, DIN, and JIS standards are followed.

• Threaded Connections: NPT, BSP, etc. (usually for smaller valves).

8. Applications:

• Liquefied Natural Gas (LNG): Valves used in LNG storage tanks, pipelines, and marine applications.

• Air Separation Plants: For gases like oxygen, nitrogen, and argon.

• Cryogenic Tankers: Used in transportation of liquefied gases at very low temperatures.

• Medical Gas Supply: For oxygen and other medical gases used in healthcare systems.

• Space and Aerospace Applications: Handling liquid oxygen and hydrogen in space exploration.

9. Standards & Certifications:

Standards:

• BS 6364: Cryogenic Valve Standard

• ASME B16.34: Valves for pressure-temperature ratings

• ISO 21011: Cryogenic vessels and equipment standard

• API 6D: Pipeline valve standards

Certifications:

• Fire-Safe certification as per API 607 or ISO 10497.

• Fugitive Emission testing to ISO 15848.

• Low-Temperature Pressure Testing: Ensures the valve’s integrity at cryogenic temperatures.

10. Testing:

• Cryogenic Testing: Performed at specified cryogenic temperatures to ensure the valve operates effectively under extreme cold.

• Pressure Testing: Hydrostatic and pneumatic tests under ambient and cryogenic temperatures.

• Leak Testing: Usually helium leak testing is performed to detect any possible leakage from the valve body or seat.

• Seat Leak Test: Conducted as per API 598 to ensure bubble-tight sealing under cryogenic conditions.