Editor's note: With the advancement and development of science and technology, the pace of socio-economic development has been continuously increasing, and the competition in various industries has also become increasingly fierce. After several decades of development, China's valve industry has been developing, performance, quality, and reliability of products. , Services, etc. have made great progress. After entering the year 2000, the valve is more intelligent, more efficient, better equipped, and more automated. Market-oriented, improve the technical content, research and development of high efficiency and low consumption, production and marketing of high-end products and high-tech products, the functional gradually to refine and diversify the direction, has become the current top priority for the development of the valve industry.

1. Valves for oil and gas wellhead devices Valves for oil and gas wellheads are mainly single gate or double gate plates conforming to the United States API6A standard, forged steel parallel gate valves with diversion holes or diversion holes, mud valves, and angled valves. Throttle valves, oilfield-specific parallel-type control valves, oilfield-specific straight-through check valves, water-injection-polymer-specific parallel-type gate valves, clamp-type parallel gate valves, pilot-operated safety valves, and check valves. Nominal pressure levels for API valves for oil and gas wells are API2000psi, 3000psi, 5000psi, 10000psi, 15000psi, 20000psi; nominal diameter is DN46～228mm (113/16in～9in); temperature grade is K (-60～182°C) , L (-42 to 182°C), P (-29 to 182°C), R (room temperature), S (-18 to 166°C), T (-18 to 182°C), U (-18 to 121°C) , V (2 ~ 121 °C); material requirements for AA, BB, CC, DD, EE, FF, HH; material performance requirements by 36K, 45K, 60K, 75K; product technical requirements by PSL1 (product specification level 1), PSL2 (Product Specification Level 2), PSL3 (Product Specification Level 3), PSL4 (Product Specification Level 4).

2. Valves for long-distance oil and gas pipelines Valves for long-distance pipelines for oil and gas are mainly single or dual gate plates that meet US API 6D standards, flat gate valves with diversion holes or non-distribution holes, and forged steel or cast steel. Body-type, top-mounted or all-welded ball ball valve; oil seal or pressure balanced plug valve; swing-type or butterfly check valve, ball check valve; pigging valve. The nominal pressure levels of these valves are CL150 (PN2.0MPa), CL300 (PN5.0MPa), CL400 (PN6.4MPa), CL600 (PN10.0MPa), CL900 (PN15.0MPa), CL1500 (PN25.0MPa), CL2500 (PN42.0MPa); nominal diameter of DN50 ~ 1500mm (2in ~ 60in); fire test technology requirements in accordance with ISO10497; valve pressure test according to ISO5208.

3. Nuclear valve valves for nuclear power use have higher technical features and requirements than conventional valves for large thermal power stations. Valves generally include gate valves, globe valves, check valves, butterfly valves, safety valves, main steam isolation valves, ball valves, diaphragm valves, pressure reducing valves, control valves, etc. The highest technical parameters for representative valves are: maximum diameter DN 1200mm ( Nuclear 3 butterfly valve), DN800mm (core 2 main steam isolation valve), DN350mm (core 1 primary circuit gate valve); maximum pressure: about 1500 pounds; maximum temperature: about 350°C; medium: coolant ( Borated water) etc. The requirements for the production of nuclear-rated valves are generally based on the nuclear industry standard EJ, the American ASME, the IEEE standard, and the Chinese valve product market of the French pressurized water reactor nuclear island mechanical equipment design and construction rules RCC-M. With the continuous development of science and technology, In the direction of high-tech, high parameters, strong corrosion resistance, and long life. Based on the analysis of valve technology at home and abroad and the analysis of valve market demand at home and abroad, we have researched the high-tech development trend and investment direction of industrial valves and valve industries in various industries in recent years.