Industrial valves · Криогенный запорный клапан

Cryogenic Shut-off Valves: High-Tech Solutions

Cryogenic shut-off valves (Cryogenic Globe Valve) from EV Group China are high-tech pipeline fittings specially designed for operation in conditions of extremely low temperatures, reaching -150°C and below. These devices are critically important for ensuring the tightness and precise regulation of liquefied gas flows, including nitrogen, oxygen, hydrogen, and liquefied natural gas (LNG), in the most demanding industrial applications.

The design of EV Group China cryogenic valves takes into account all critical physicochemical changes that occur with materials at ultra-low temperatures. This guarantees stable and safe operation of cryogenic media transportation and storage systems, preventing material embrittlement and ensuring long-term operation.

Key Design Features of Cryogenic Valves

Unlike standard pipeline fittings, EV Group China cryogenic valves feature a number of unique engineering solutions that ensure their reliability in deep cold conditions:

High-strength cryogenic-resistant materials: Specialized alloys are used for the manufacture of bodies and internal elements, which retain high ductility, impact strength, and plasticity at cryogenic temperatures. This prevents phase transitions and embrittlement that are characteristic of ordinary metals in cold conditions.
Extended stem (bonnet): The design with an extended bonnet moves the packing assembly and drive mechanism (handwheel, gearbox, pneumatic or electric actuator) out of the zone of direct exposure to low temperatures. This solution eliminates freezing of seals, ensures easy operation, and prevents loss of stem tightness, which is critically important for safe and efficient operation.
Effective thermal insulation: Advanced methods and materials are used to minimize heat input from the environment to the working cryogenic medium. This not only reduces cold losses but also protects operating personnel from thermal burns upon contact with the valve body.
Specialized seals: Modern polymer and composite materials, such as PTFE (fluoroplastic) and PCTFE, are used as sealing elements. These materials retain their elasticity and sealing properties over a wide range of cryogenic temperatures, ensuring flawless operation in contact with liquefied gases.

Materials of Manufacture and Their Selection

The selection of materials for EV Group China cryogenic valves is carried out based on a thorough analysis of operating conditions, including the type of medium, temperature regime, and required pressure. This ensures maximum compatibility and durability:

Corrosion-resistant steel (AISI 316/316L): This is the optimal choice for most cryogenic applications due to its high nickel and molybdenum content, which provides excellent strength, corrosion resistance, and retention of mechanical properties at low temperatures.
Nickel-based alloys (Inconel): Used in the most critical components and at extremely low temperatures, where enhanced heat resistance, cryogenic ductility, and creep resistance are required.
Bronze and brass: Used in limited cases for certain components where their unique properties (e.g., low friction) may be an advantage, with strict adherence to pressure and temperature tolerances.
Fluoroplastics (PTFE/PCTFE): Are the standard for sealing elements due to their chemical inertness, low coefficient of friction, and ability to retain elasticity at ultra-low temperatures, guaranteeing reliable sealing.

Where Applied

EV Group China cryogenic shut-off valves are widely used in critically important industries where reliable control over the flows of ultra-cold media is required:

Oil and gas industry: In LNG terminal infrastructure, gas processing plants, liquefied natural gas storage and transportation systems, as well as in gas separation units.
Chemical and petrochemical industry: For the processing, storage, and transportation of cryogenic chemical reagents, such as liquid oxygen, nitrogen, argon, hydrogen, and helium.
Aerospace industry: In rocket fueling systems with liquid propellant (e.g., liquid oxygen and hydrogen), test benches, and equipment for spacecraft.
Medicine and biology: In cryostorage facilities for biomaterials, medical gasifiers, and medical gas supply systems.
Research centers: In cryogenic installations, experimental setups, and laboratories for research in the field of low-temperature physics.

What to Replace / Analogues

When it is necessary to replace cryogenic shut-off valves or select analogues, several key aspects should be considered:

Body material: Alternatives to AISI 316/316L may include other austenitic stainless steels with high nickel and chromium content, such as AISI 304L for less aggressive media or specialized nickel alloys (Hastelloy, Monel) for extremely corrosive or ultra-low temperature conditions. It is important to ensure that the selected material has the necessary cryogenic resistance and is not susceptible to cold brittleness.
Seal type: In addition to PTFE and PCTFE, specialized composite seals based on graphite or metal-to-metal seals with cryogenic treatment may be used in some cases, especially for high pressures or abrasive media. However, their application requires careful analysis of compatibility and temperature range.
Design: In addition to standard ball and plug valves, there are also specialized diaphragm valves and bellows valves for cryogenic applications, which may offer enhanced tightness or lower leakage probability, but may have limitations in flow capacity or pressure.
Manufacturers: Various manufacturers of cryogenic fittings are represented on the market. When choosing an analogue, it is important to compare not only technical characteristics but also the manufacturer's reputation, the availability of certificates of compliance with international standards (ISO, ASME, API), and the possibility of obtaining full technical support.

What to Clarify with the Supplier

Before purchasing cryogenic shut-off valves from EV Group China or any other supplier, it is extremely important to obtain comprehensive information to ensure that the equipment meets your technical requirements and safety standards:

Certification and standards: Request full certificates of compliance with international standards (e.g., ISO 9001 for quality management systems, ASME B16.34 for valves, API 600/624 for stem leakage tests) and national regulations. Clarify whether the valves have undergone cryogenic leak tests at operating temperature.
Materials and their origin: Demand confirmation of the steel grades and other materials used in the design, including chemical composition and mechanical properties at low temperatures. Specify raw material suppliers and the availability of relevant material certificates.
Technical documentation: Request detailed drawings, assembly diagrams, product passports, operation and maintenance manuals, as well as graphs of operating characteristics versus temperature and pressure.
Operating conditions: Clearly specify the range of operating temperatures, pressure, type of working medium (liquefied gas), and required flow capacity. Clarify what warranty is provided for the operation of the valves under these conditions.
Testing and quality control: Inquire about quality control procedures during manufacturing, including non-destructive testing (ultrasound, X-ray), hydraulic, and pneumatic tests. Ask for test protocols for a specific batch.
Service life and maintainability: Clarify the estimated service life of the valves, maintenance frequency, availability of spare parts, and the possibility of repair or technical maintenance by the supplier or an authorized service center.
Packaging and transportation: Ensure that the valve packaging complies with the requirements for transporting high-tech equipment and provides protection against damage and contamination.