The pressure gauge thermometer is based on the principle of liquid or gas or low boiling point liquid and saturated vapor in a closed container, and it is measured by volume expansion or pressure change after heating, and the pressure is used to measure this change, so as to measure the temperature.
The pressure meter type thermometer consists mainly of the following three parts:
1. - temperature temperature package is directly related to the medium contact to feel the temperature change of the element, so it has high strength, low expansion coefficient, high thermal conductivity and corrosion resistance and other properties, according to the filling of working medium and different medium, temperature of available copper alloy steel or stainless steel.
2. capillary, a seamless tube made of copper or steel, used to transfer pressure changes.
3. spring tube - it is the elastic element used in the general pressure gauge.
The pressure gauge thermometer is an industrial instrument, which is characterized as follows:
(1) for measuring the temperature of 0~300 DEG C, allowing the basic error of no more than 1.5 or 2.5 percent percent.
(2) it can be made into an indicator type, a recording type, and it is easy to make a temperature signal and a temperature regulator.
(3) the temperature can be measured in a long distance.
(4) the structure is simple and the price is cheap.
(5) not afraid of vibration, you can not use power.
(6) when the distance is far away, the hysteresis of the instrument is larger.
Classification of pressure gauge thermometers:
(I) liquid pressure gauge thermometer
(two) a gas gauge thermometer
(three) error analysis of a steam pressure meter type thermometer type thermometer
In addition to the inaccuracy of the size of the pressure gauge thermometer, the clearance of transmission and friction will cause errors, and some of the following factors will cause errors.
(1) the influence of the depth of the partial immersion in temperature;
(2) the influence of ambient temperature;
(3) the influence of the height of the liquid column;
Add: Liuxia Town, Xihu District, Hangzhou, Zhejiang province China