Valves are essential fluid control equipment in various sectors of the national economy, including petroleum, chemical, power plants, long-distance pipelines, shipbuilding, nuclear industry, various low-temperature engineering, aerospace, and offshore oil extraction. The development and needs of the above-mentioned industries have driven the development of the valve industry. In recent years, while meeting the new requirements for high parameters in various aspects, close attention has been paid to the structure, materials, and production process of valves, as well as how to better improve performance, feasibility, and reduce costs.?



Valves are products that involve a wide range of categories, complex varieties, and large quantities. Their quality and technical level directly affect the development of various sectors of the national economy. Therefore, strict control of internal quality is required for valves. Some valves need to be recognized by international authoritative institutions in order to open up sales channels. For example, some power engineering valves and nuclear power valves require approval marks from the American Society of Mechanical Engineers (ASME) in order to be purchased. ASME currently uses five markings, including "NPT". Valves used in the petroleum industry must obtain the American Petroleum Institutes "API" mark in order to open up sales channels.?




With the rapid development of modern industries abroad, the production of valve industry has also developed rapidly. Before the 1950s, many countries had formed independent valve specialties and their industry systems, with valve industry organizations or academic organizations for valve specialties. For example, valve industry associations exist in Europe, the United States, the United Kingdom, and other countries; Japan has valve industry associations and valve research associations; Dong Europe and the former Soviet Union have valves. Design and Research Institute. These valve industries and professional organizations are all established to improve production technology and meet the needs of external competition