As its name suggests, cryogenic valves are designed for very cold applications. As a result, they are most commonly used by companies working with liquefied natural gas (LNG) or compressed natural gas (CNG). For example, the oil and gas industry generally uses cryogenic temperature range -238 degrees Fahrenheit (-150 degrees Celsius). In addition, some gases are not considered cryogenic because the temperature is not very low, but because it takes more than just increasing pressure to compress the volume. The cryogenic valve is designed to store and transport safely and effectively this cryogenic gases.kp-lok.com
Cryogenic valves are different from other standard valves on the modern market because they can operate at temperatures as low as -196 degrees Celsius and a maximum pressure of 750 psi.
Working cryogenic valve
The cryogenic valve remains in its naturally closed position to maintain cryogenic gas or other safe media. Cryogenic valves are often designed to respond to the high pressure that pushes the valve to the open position to allow gas or other fluid to flow easily. In this way, the flow continues to open until the pressure drops again; it is sealed with a hermetically sealed metal barrier to prevent leaking leaks at this time.
Working Mechanism of the Cryogenic valve
In the oil and gas industry, the low temperature zone begins at -150 ° C (-238 ° F). In addition to this temperature range, some gases are considered cryogenic (low temperature) because they must exceed the pressure increase to compress their volume. A temperature higher than a cryogenic temperature up to 37 ° F (3 ° C) is called refrigeration.
Knowing where the cryogenic temperature starts is very important for selecting the valve. When planning to choose a valve for long periods of operation, there are several things you need to know about low temperatures.
“The valve industry is moderate,” said Nathaniel Paxton, TBV product manager. Continuous temperatures below -100 ° F (-73 ° C) are considered a cryogenic service, and the usual rule is to ensure that special valves are prepared.
Choose the right cryogenic valve
There are five types of cryogenic valves that are suitable for use in cryogenic media. Each of these types has its own properties that apply to certain applications and do not apply to other types.
- Globe Valves: Due to its sphericalvalve, it has an internal movable disc and then rotates 90 degrees to the coordinated body plane. These cryogenic valves offer greater reliability in terms of long-term sealing performance, are prone to moisture, and flow is very important in most situations and is not very good.
- Ball Valves: These valves use balls as closures and usually contain a Teflon body layer. It has better flow characteristics than a globe valve, but it tends to move along the joint and the ball itself. Therefore, it is very useful for applications that require unlimited traffic paths.
- Top Entry Ball Valves: Like the standard ball cryogenic valve, this new model has a one-piece design and a butt welded connection for easy maintenance. The lack of mechanical connections is also ideal for fire protection applications.
- Gate Valves: The gate valve uses a wedge-type gate as a shutter that pivots parallel to the seat of the engaged body. They have good flow properties but are similar in ball valves because they are subject to tear and wear.
- Butterfly valve: The butterfly valve is part of a quarter-circle house and uses a disc in the middle. The disc can make the cryogenic valve shorter than the above options, low cost, light weight, simple and easy to use. However, excessive use can lead to a short life.