Insulation thermometer temperature measurement on the lid is what principle

Heat preservation and the thermometer on the lid will generally choose bimetallic thermometer, because the temperature stability is better, and long service life. The bimetallic thermometer works by using two different metal expansion degree during temperature change the principle of work. The main component is a use two or more pieces of metal laminate composed of multilayer metal together. To improve the temperature measuring sensitivity, is usually made of metal spiral coil shape. When multi-layer metal temperature change, the layers of metal expansion or contraction, makes the spiral coil rolled up or let go. As a result of the spiral coil end fixed and the other end connected to a free rotating pointer, therefore, when the bimetallic strip feel the temperature change, Pointers can be on a circular dividing scale to indicate the temperature. Bimetallic thermometer is a kind of field detection instrument suitable for the measurement of low temperature, and can be used to directly measure the temperature of the gas, liquid and steam, features: no mercury pollution, easy reading, long service life. （ Heat preservation pot thermometer generally adopt the thermometer, so don't worry there are mercury pollution) 。