The principle of the pressure thermometer is based on the change relationship between the saturated vapor pressure and temperature of the evaporating liquid in the closed temperature measurement system, and the temperature measurement is carried out. When the temperature bulb feels the temperature change, the saturated steam in the closed system will generate corresponding pressure, which will cause the change of the curvature of the elastic element, so that the free end will be displaced, and then the displacement will be changed into the indicated value by the gear amplifying mechanism. The package is small in size, fast in response, high in sensitivity, and intuitive in reading. It almost combines all the advantages of glass rod thermometers, bimetal thermometers, and gas pressure thermometers. It can be manufactured into shock-proof and anti-corrosion types, and can realize remote transmission contacts. Signal, RTD signal, 0-10mA or 4-20mA signal. It is currently the most widely used and most comprehensive mechanical temperature measuring instrument. Parameters of pressure thermometer ● Explosion-proof grade: dⅡBT4, dⅡCT5, dⅡBT6, dⅡCT6 ● Ambient temperature: -20～45°C : 34S