Forged steel low-temperature gate valve

The forged steel low-temperature gate valve is a high-performance industrial shut-off device specially designed for extreme low-temperature and cryogenic medium storage and transportation systems. Its core application temperature can be as low as -196℃ (-320℉), and it can be reliably applied to the harsh working conditions of liquefied natural gas (LNG), liquid oxygen, liquid nitrogen, liquid argon, liquid ethylene, etc. The main body of this valve is made of high-quality forged steel, which has a more compact and uniform metal structure, higher mechanical strength, and better low-temperature impact toughness compared to traditional castings. This fundamentally avoids the risk of brittle fracture of the material in ultra-low temperature environments, ensuring the intrinsic safety of the valve under cryogenic conditions. 

To address the core challenges of the low-temperature system - minimizing heat transfer and ensuring operational reliability, this valve typically adopts a long-stem design. This slender neck structure forms an effective "thermal barrier" between the valve body and the upper operating mechanism, significantly increasing the length of the heat dissipation path, thereby minimizing the conduction of ambient heat to the low-temperature medium. This design not only effectively prevents the risk of abnormal vaporization and pressure rise of the medium inside the valve due to continuous external heat input, but more importantly, it elevates the key operating components such as the packing gland, valve stem nut, and handwheel to a position far away from the cryogenic fluid, keeping them in an area close to the ambient temperature. This ensures the sealing performance of the packing, the flexible movement of the valve stem, and the convenience and safety of operation, completely solving the problems of component freezing and jamming caused by low temperatures. 

According to the different requirements of users for sealing reliability, maintainability and installation specifications, the valve provides two classic high-end valve cover connection schemes: The bolted valve cover is connected by a group of high-strength bolts and is combined with an annular gasket made of 316 stainless steel wrapped with flexible graphite to achieve static sealing. This structure is convenient for inspection and internal maintenance of the valve after use. The welded valve cover is sealed by pre-tightening with threads or directly by full welding, achieving a permanent and absolutely reliable seal between the valve cover and the valve body, completely eliminating the possibility of external leakage at this location. It is especially suitable for critical situations where no leakage points are allowed or for direct burial installation environments. 

The design and manufacture of this valve strictly follow international authoritative standards such as API 602, MSS-SP-118 and BS 6364 (specific standards for low-temperature valves). Its inspection and testing are carried out strictly in accordance with API 598 standards. The valve adopts a exposed stem support design, making the opening and closing status clearly visible; it provides options for full-diameter or reduced-diameter flow channels; the end connection can use socket-welding in compliance with ASME B16.11 or NPT threads in compliance with ANSI/ASME B1.20.1, demonstrating excellent system adaptability. In addition, its detailed designs such as the integral upper sealing seat and valve seat pressure balance holes further enhance its safety and functionality, and are indispensable key safety equipment in liquefied natural gas receiving stations, air separation units, low-temperature storage and transportation, and chemical processes.

1. Professional deep cooling design and elongated valve cover structure 

The valve is specifically optimized for ultra-low temperature conditions. Its distinctive elongated valve cover is the core factor ensuring its low-temperature performance. This structure significantly reduces heat loss and heat intrusion by increasing the length of the cold bridge. It not only protects the upper operating mechanism but also prevents the packing from failing due to low temperatures. At the same time, it ensures that the valve can still be opened and closed easily and reliably in an extreme environment of -196℃, achieving the unity of operational safety and operational convenience. 

2. Dual-combination valve cover sealing solution, balancing maintainability with absolute sealing 

We offer two top-level valve cover solutions: the bolt-wrapped gasket type and the fully welded threaded type. The former is easy to disassemble and maintain, making it convenient for upkeep; the latter provides a permanent static seal, achieving "zero leakage". Users can choose flexibly based on the importance of the pipeline, maintenance strategies, and safety levels, to meet various needs ranging from routine maintenance to lifetime maintenance-free. 

3. The forged steel valve body and reinforced structure provide outstanding low-temperature toughness. 

The valve body is made of forged steel, with no defects in its internal structure and excellent pressure-bearing capacity. Its low-temperature impact toughness is much better than that of castings. Combined with self-centering pressure plates, integral upper sealing seats (facilitating on-site replacement of packing under pressure), and forged valve stems, etc., these enhanced designs ensure the overall structural integrity and extremely long service life of the valve under low-temperature, high-pressure, and temperature fluctuation conditions. 

4. Adhere to strict international standards and support deep customization 

The product fully complies with standards such as API, ASME, and BS, ensuring the universality and quality reliability of global projects. At the same time, it supports highly customized services such as extending the length of special valve covers, conducting special low-temperature performance tests, and selecting PTFE packing. It can also design soft-sealed gate plates according to customer needs, precisely matching specific media and process requirements. 

5. Convenient operation and high system integration capability 

The exposed stem structure makes the switch position clearly visible. The valve can easily be adapted to manual gearboxes or electric and pneumatic actuators, covering the full range from local operation to remote automatic control. The design of the valve seat pressure balance hole can effectively reduce the operating torque under high pressure differences, making the opening and closing of large-diameter valves more effortless.