Several installation forms of bimetallic thermometer

The working principle of bimetallic thermometer is to use two metals with different temperature expansion coefficients. One end is welded at the fixed point, and the other end is twisted and deformed when the temperature changes, which is converted into the deflection angle of the pointer to indicate the temperature. The core pulling type refers to that the bimetallic temperature sensing element can be pulled out and replaced from the outer protective tube. It is the most widely used field indicating thermometer.

According to the connection direction between the bimetallic thermometer dial and the protective tube, the bimetallic thermometer can be divided into four types: axial type, radial type, 135 ° direction type and universal type.

1. Radial bimetallic thermometer: the pointer plate is connected in parallel with the protective tube;

2. 135 ° bi metal thermometer: the pointer plate is connected with the protective tube at 135 °;

3. Universal bimetallic thermometer: the connection angle between the pointer plate and the protective tube can be adjusted arbitrarily;

4. Axial bimetallic thermometer: the pointer plate is vertically connected with the protective tube.