The structure of the pressure type thermometer mainly by thermal bubble, capillary tube, the coil spring tube ( Or more lap spiral pipe) A closed system composed of three parts, the temperature measurement system based on closed in saturated vapor pressure of liquid evaporation ( Or gas pressure) And the change of the relationship between temperature, closed system internal work principle of the volume of a material change with the temperature or pressure, suitable for measuring the within 20 meters of which do not corrode copper and copper alloy liquids, gases and steam temperature. Pressure type thermometer can be divided into three types of steam pressure type thermometer, gas pressure type thermometer, liquid pressure type thermometer, are classified according to different forms.
steam pressure type thermometer, temperature measuring system, the evaporation part filled with low boiling point liquid heat medium pressure type thermometer. The pressure type thermometer is the use of low boiling point of liquid evaporation hatosy vapor pressure varies with the temperature for temperature measurement, so hatosy vapor pressure changing with temperature is line. Gas pressure type thermometer, all full of gas in the temperature measuring system of heat medium pressure type thermometer, the thermometer is equal scale, but the bulb volume is larger, so the thermal inertia. Temperature measurement system in all filled with liquid heat medium pressure type thermometer, the thermometer is equal scale, small bulb, thermal inertia is small.