Nuclear power valves are essentially identical to those used for thermal power generation. High-pressure and large-diameter pipes mainly use gate valves. Low-pressure large-diameter pipes use butterfly valves. Small-diameter auxiliary pipes are mostly used with stop valves or angle stop valves. There are almost no differences between check valves, safety valves and regulating valves used in other fields. However, among the valves for nuclear power, the valves used in the primary cooling system are not allowed because of the radioactivity in the internal medium Leakage is a valve product that requires high reliability and is stricter than other valves in quality management. In addition the valve environment also has radioactive energy, be sure to consider the use of special materials and structures suitable for atomic furnace. For the occasion of molten metal and gas penalties, the valve for water cooling furnace, the technical standards in ASME have detailed provisions of the standard valve as a pressure vessel, set forth the technical standards to ensure its performance. Nuclear valve features are as follows: 1. Requires a high degree of reliability 2. To take measures to eliminate external leakage 3. The composition of materials selected radioactive materials