Cryogenic valves buying guide, its uses, and benefits
Cryogenic valves can survive and function successfully at subzero temperatures. They are used in a range of industries, including the petrochemical and aerospace industries, where fluids at such high temperatures must be handled. Although the definition of cryogenic temperature varies by industry, cryogenic valves typically function between -40°F (-40°C) and -320°F (-196°C).
Cryogenic Valves and Their Applications
Cryogenic valves are typically found in industrial facilities to take advantage of the advantages of performing procedures at cryogenic temperatures. As a result, the sections that follow showcase some of these uses.
Terminals and Plants for Liquid Nitrogen Gas (LNG)
Cryogenic valves are used in the oil and gas sector to regulate liquified gases such as liquid nitrogen, methane, and helium. Because of the convenience and safety of non-pressurized storage and transportation, these components drop to cryogenic temperatures and stay liquid. As a consequence, bigger amounts may be delivered or stored for an extended period while the pipe system functions at much lower pressure levels. To avoid corrosion issues downstream, it is vital to remove condensate, moisture, CO2, and H2S before chilling these gases into liquid.
Since World War II, the area of cryogenics has seen rapid advancement, culminating with Ed Busch's commercialization in 1966. Busch increased metal tool design life by up to two to four times by using cryogenic tempering rather than heat treatment. As a consequence, cryogenic valves and associated equipment are now ubiquitous in steel manufacturing facilities. Another use is the freezing of meals and biotech items like vaccinations.
Applications in Aerospace
Cryogenic fuels have achieved widespread acceptance in the aircraft industry throughout the years. Liquid hydrogen and liquid oxygen are often used as space shuttle propellants, either alone or in conjunction with jet fuel. Cryogenic valves must be present in such systems.
Cryogenic Valve Types
As previously stated, there are several cryogenic uses. Similarly, other valve types may be used in similar applications, each with its own set of advantages. As a result, it is critical to pick the appropriate type for a given application. A tight shut-off is a fundamental property of all cryogenic valves. Cryogenic fluids are delicate, and any leakage may cause costly and dangerous damage.
Cryogenic Butterfly Valves
The triple-offset butterfly valve is an excellent choice for cryogenic applications. This is owing to its non-friction, metal-to-metal seal, which guarantees bubble-tight shut-off and the sealing mechanism's long-term integrity. Furthermore, they provide rapid opening and shutting motion and are an excellent alternative for remote control. The Durco TX3 butterfly valve is an example of this, with superior shutdown capabilities, low torque, and decreased wear.
Valves for Cryogenic Globes
These valves are spherical in form and feature a disc that rotates 90 degrees to the plane of their body seat. As a result, it is useful for long-term sealing. However, they may not withstand erosion for long and are not suggested for high-flow systems. To prevent erosion, globes should ideally come with a complete Stellite valve trim. Cryogenic fluids lose their lubricity over time, and Stellite aids in reducing valve wear and tear.
Ball Valves for Cryogenic Environments
Double-seal ball valves such as the L&T and AMPO Poyam are the most often used valves for liquid gas applications. They provide superior flow characteristics to globe valves in general. They are also highly effective at establishing a tight seal. They also have a sufficiently high vapor space to facilitate gasification in the region underneath the gland. As a result, since heat transmission between the interior and outside of the valve is restricted, this maintains the gland packing around the ambient temperature. Nonetheless, because of wear problems along the seals and ball, they are preferred in applications with an unobstructed flow channel.
Gate Valves for Cryogenic Environments
The gate of a conventional cryogenic gate valve is wedge-shaped and opens and closes in line with the mating body seat. As a consequence, there is very little pressure decrease when the valve is completely open. As a result, it has favorable flow properties. Gate valves such as the Poyam, L&T, and the smaller forged NEWCO Douglas-Chero are chosen for larger valve sizes over ball valves, which may be more expensive. However, gates are more difficult and costly to operate than butterfly valves, particularly as their size grows, making them unsuitable for remote control. If gates are often opened and closed, they might suffer from wear and tear. The fact that gate valves have metal-to-metal sealing surfaces means that they are not more vulnerable to cold flow than Teflon seals in ball valves.
To guard against erosion, gate valves should have a Full Stellite Trim (Stellite on both the seat and the disc). Cryogenic fluids lose their lubricity over time, and Stellite aids in reducing valve wear and tear.
Testing of Cryogenic Valves
Cryogenic valves, like any other form of valve, are subjected to valve testing based on the type of valve in use. Nonetheless, some of the tests that are usually required are as follows:
- Shell Strength Test: Depending on the system's operating pressure and other features, this might be hydrostatic or pneumatic. According to the guidelines, it should be done at 1.5 times the system's maximum operating pressure.
- Shell and Seat Leak Test: The system is inflated to 1.1 times the maximum operating pressure for pneumatic testing. The threshold for hydrostatic testing is 1.3 times the maximum operating pressure.
- Cryogenic Prototype and Production Test: These tests are carried out in line with the BS 6364 method.
Why is cryogenic valve stems so long?
Cryogenic Valves Design Consideration
All cryogenic valves for liquid natural gas, methane, oxygen, ammonia, and other uses are custom-made. Cryogenic valves often feature long bonnets to keep the valve stem seals away from the cold source. This will serve two critical purposes:
- The valve stem seals will be quite hot, and there will be enough distance between the pipeline and the lever/handwheel that operates the valve to provide insulation.
Cryogenic Valves Dimensions and Pressure Rating
Cryogenic valves for industrial use are available in a variety of sizes and pressure classifications. Sizes typically vary from 1/8 inch to 88 inches (3 mm to 2240 mm). Cryogenic valves have pressure ratings ranging from ultra-high vacuum pressure to 700 bar. All of these valves can operate at temperatures as low as -2540 C. (-4250F).
Cryogenic Valves Characteristics
- Cryogenic valves should be lightweight because the lightweight valve mass is simpler to cool from ambient to cryogenic temperature.
- Lighter cryogenic valves often have lower conductivity, which aids in decreasing heat inflow when compared to heavier structures. Welded valves, on the other hand, are superior.
- Cryogenic valves should be installed in a clean environment and should be lubricant-free or use cold-service suitable lubricants. Documented cleaning techniques must be obtained when buying a cryogenic valve to verify and follow correct processes throughout the assembly process.
How is a Cryogenic Valve placed in a piping system?
The valve is positioned such that the stem has a minimum inclination of 15 degrees to the horizontality to maintain a warm gas seal. To simplify piping arrangements, the valve should be installed in a horizontal pipeline.
What does GMK provide?
GMK provides you with the best quality cryogenic valves. They have different types of valves. They have a cryogenic ball valve, Cryogenic triple offset butterfly valve, forged steel cryogenic ball valve, forged steel cryogenic ball valve, forged steel cryogenic globe valve, cryogenic gate valve, cryogenic globe valve, and many more.
Check the features of the cryogenic triple offset butterfly valve:
Cryogenic Triple Offset Butterfly Valve
GMK cryogenic triple offset butterfly valve switches important operations. GMK butterfly valves use three offsets for bubble-free shut-off. Our passion is shown in the high quality of our items, which may be customized and survive harsh climates.
- Metallic seat.
- The body and disc have been RT-tested for quality.
- Designed for low temperatures.
- Extensions protect actuators.
- The package is designed for cold settings.
- The unusual structure of the seat and seal function well together.
- Possesses dignity, a reliable seal, and a nice surface.
GMC’s unique customer service will ease your interactions with the facility. They provide affordable valve services. Cryogenic valves find widespread use in the liquefied natural gas (LNG), petrochemical, food processing, or air separation sectors. GMC’s cryogenic valves feature stainless steel bodies. GMK constantly enhances its goods and seeks new ideas to be ahead of the market. With their expertise and experience, they can help you expand you