Caofeidian port is a "diamond" port site, which can build more than 2.6 million ton berths. The surrounding hinterland is the most concentrated area of coal, steel, building materials, electric power, chemical and other energy raw materials production in China, and it is also one of the energy raw materials industrial bases that the state is striving to build. A total of 12 Hertz vacuum contactors are used in this project.