Installation requirements for cryogenic valves
Because of the special structure of the cryogenic valve, the installation of cryogenic valve also has its special requirements. Because of the long neck bonnet design of the cryogenic valve, the valve stem must be installed at a 45-degree Angle vertically up and should be avoided in vertical lines. Otherwise, the cryogenic medium will fill the extended portion of the bonnet, causing valve packing failure and passing the cold amount to the valve handle, causing personal injury to the operator. For low-temperature valve with pressure relief structure, special attention should be paid to the requirements of pressure relief direction when installing the valve. The direction of valve pressure relief should be marked on the process flow chart, and reflected in the pipeline axial diagram (this is extremely important, extremely important, extremely important), if it is necessary to set a pressure relief hole and not set, the valve closed, the liquid in the valve cavity by heat gasification, easy to cause the valve body burst. If the direction of pressure relief is wrong, the combustible or toxic process medium may be discharged to the side of operation and maintenance, causing casualties.
Cryogenic valve manufacturing
The strict manufacturing process and special equipment are adopted for the low-temperature valves produced, and strict quality control is carried out for the processing of parts. After special low-temperature treatment, the rough parts are placed in the cooling medium for several hours (2-6 hours) to release the stress, ensure the low-temperature performance of the material, ensure the precision machining size, to prevent the valve in low-temperature working conditions, due to temperature changes caused by deformation and leakage. Valve assembly and the common valve is also different, the parts need to undergo strict cleaning, remove any grease, to ensure the performance.
