There are many kinds of pressure instruments, including pointer display type and digital display type, which can also be used in nuclear power plant in function. Pressure data can be detected when leaving the site. Today we are going to talk about diaphragm pressure instruments. In daily industrial production, various pressure gauges are essential as general measuring meters. Diaphragm pressure gauge is a special product used to measure specific media in pressure gauge. It can measure the medium with strong corrosion, high temperature and high viscosity. At present, fluid medium measurement related places with special properties such as petroleum, chemical industry, chemical fiber and pharmacy are widely used. Diaphragm pressure instruments are widely used in the field of industrial production. Especially in the working environment with high temperature and high corrosion, it plays a very important role.