As an important part of modern energy supply, the safety performance of nuclear power plants is very important. In the complex system of a nuclear power plant, the valve is only an accessory, but its role cannot be ignored. The valve plays a vital role in the normal and safe operation of the nuclear power plant and is an essential and important part of the safe operation of the nuclear power plant.

The operating environment of nuclear power plants has the characteristics of high radiation, high temperature and high pressure, which requires the valve to have good radiation resistance, high temperature resistance and high pressure resistance. The medium in the nuclear power plant, whether it is the coolant water in the primary circuit, or the steam and water in the second circuit, contains certain corrosive substances. Therefore, the material of the valve has excellent corrosion resistance to resist the erosion of the medium on the valve. At the same time, the valve also needs to be used in a variety of design conditions (including normal, abnormal, critical and accident), and even in extreme situations such as earthquake disasters or LOCA water loss accidents, to maintain the integrity and operability of the valve equipment.

The safety role of valves in nuclear power plants is mainly reflected in the following aspects:

First of all, the valve is the key control equipment for the transmission of media in nuclear power plants. Various systems in a nuclear power plant, such as the reactor cooling system, steam generator system, main water supply system, etc., need to control and regulate the flow of media through valves. The precise control and rapid response of the valve can ensure the stability and safety of the various systems in the normal operation of the nuclear power plant and in emergency situations.

Secondly, the valve plays an important role in the emergency treatment of nuclear power plant accidents. In the event of an accident at a nuclear power plant, the valve can quickly cut off the accident source and prevent the accident from expanding. For example, in the reactor cooling system, safety valves and shut-off valves can be quickly closed at high temperatures and pressures to prevent reactor explosions. The accuracy of these valves is directly related to the effect and safety of nuclear power plant accident emergency treatment.

In addition, the valve also undertakes the prevention and control of radioactive material leakage in the nuclear power plant. The coolant in the primary circuit of a nuclear power plant will carry strong radioactive materials as it passes through the reactor core. Therefore, the valve in contact with the primary coolant has good radioactive shielding capability and radiation resistance to prevent radioactive substances from leaking into the surrounding environment and causing harm to personnel and equipment. These valves are usually double-sealed and are equipped with a radioactivity monitoring device to monitor the sealing status of the valve in real time and ensure that the radioactive leakage is controlled at a very low level throughout the service life of the valve.