Cryogenic stainless steel ball valves are mainly used in chemical plants, such as ethylene and liquefied natural gas, and output liquid cryogenic media, such as ethylene, liquid oxygen and liquid hydrogen. These types of media are not only flammable and explosive, but also vaporize as the temperature increases, and the vaporized volume is hundreds of times the volume expansion. Additionally, these media are highly penetrating, leaky and difficult to process and manufacture.

1. The material of the pressure-resistant part can withstand the expansion and contraction caused by the change of the medium temperature, and the structure of the sealing part will not be deformed when the temperature changes. When used in operating conditions below -100°C, valve parts must be cold treated after completion. That is, the part must be cooled by immersing it in a tank of liquid nitrogen. When the temperature of the part reaches -192°C, hold it for 1-2 hours before taking it out. The exterior of the box is naturally machined to room temperature and has two reheat cycles.

2. The bonnet adopts a long-strength structure, which is designed to protect the function of the stuffing box, keep the stuffing box away from low temperature, and ensure the sealing effect of the packing. At the same time, cold insulation materials can be wrapped to prevent loss of cold energy. The neck length of the long neck can be selected in various lengths according to the operating temperature and the thickness of the insulation material. When reducing the packing sealing effect, grease can be added from the center of the stuffing box to form an oil seal layer, thereby reducing the pressure difference in the stuffing box and improving the sealing performance.

3. If the working temperature is lower than -100°C, the valve stem material is chrome-plated or nitrided to increase the surface hardness of the valve stem and improve the reliability of the packing seal.

4. The low temperature stainless steel ball valve has a structure to prevent abnormal pressure rise. When the low temperature valve medium evaporates, the volume expands rapidly and the pressure rises abnormally. When the pressure in the valve chamber rises, both the valve chamber and the inlet are connected, or a pressure relief valve is installed at the valve inlet to ensure the safe use of the valve.

5. The gasket of the low temperature stainless steel ball valve has reliable sealing and resilience at room temperature, low temperature conditions and temperature changes.

The advantages of low temperature stainless steel ball valve

1. Low fluid resistance

2. Simple structure, relatively small size, light weight and easy maintenance.

3. Good sealing performance.

4. Not limited by the installation direction, the flow direction of the medium is arbitrary.

5. No vibration and low noise.