In recent years, the development of foreign nuclear power plants has been relatively rapid. The largest unit has reached 1300MW and is manufactured by KWU of Germany. The Qinshan nuclear power plant produced by China is a 300MW unit. The Daya Bay Nuclear Power Plant in Guangdong Province is a 900 MW unit imported from France.
The light water reactor is the main reactor of the current nuclear power plant, and it is divided into two types: pressurized water reactor and boiling water reactor. About 70% of the millions of nuclear power plants (over 900 MW) in the world are pressurized water reactors, and about 20% are boiling water reactors. The main large forgings of nuclear power plants can be divided into two major categories: pressure shells and internal components.
The pressure shell is a key component of the nuclear equipment. It is formed by welding the forgings of the cylinder flange, the nozzle section, the nozzle, the upper cylinder, the lower cylinder, the cylinder transition section and the bolt. The material of the pressure shell is mostly SA508C1.3. The dimensions of the 1100MW boiling water reactor pressure shell cylinder flange parts produced by Japan Casting and Forging Steel Co., Ltd. are: outer diameter 7080mm, inner diameter 6400mm, height 848mm, and forged by 190t steel ingot on 8000kN press. In cooperation with Japan KWU, Nippon Steel Works Co., Ltd. forged four 1200-1300MW four-circuit pressurized water reactor pressure vessel cylinder forgings with four 400t steel ingots. The forgings are 5750mm in outer diameter, 527mm in wall thickness and 2550mm in height. Up to 190t, its material is SA508C1.2.
The internal components of the reactor are operated under severe conditions such as high temperature, high pressure, strong neutron irradiation, boric acid water corrosion, erosion and hydraulic vibration, so 18-8 austenitic stainless steel is used for the production. China's Qinshan nuclear power plant is a pressurized water reactor nuclear power plant. The stainless steel forgings used in the pile are produced by the former Beijing Heavy Machinery Plant. The weight of the basket bottom forgings is 22.4t, the size is 3100mmx360mm, and it is produced with 43t weight 0Crl8Ni9Ti steel. It is now installed and connected to the grid at the end of 1991.