In the production process, it is necessary to measure the crystalline density of sodium alum dihydrate salt, and the foreign brand nuclear densitometer was originally used. The equipment needs to be maintained regularly, and it needs to be subject to the annual inspection and supervision of the Emergency Bureau and the Public Security Bureau, and the maintenance personnel must also have corresponding qualifications. The mass flowmeter of Tianxin Instrument, a subsidiary of Jinka Intelligent, can directly measure the mass flow, density and temperature of the medium. While accurately measuring the crystal density of sodium alum dihydrate, it can also additionally measure the mass flow. Therefore, it replaces the traditional nuclear density meter, completely eliminates radiation risks, simplifies the production management process, and wins customer recognition.