How to differentiate between industrial bimetallic thermometer and mercury thermometer?

Our daily life and the relationship of the thermometer is becoming more and more closely. All kinds of full of beautiful things in eyes of thermometer. Today we're going to teach you how to distinguish between industrial bimetallic thermometer and mercury thermometer used in industry. Bimetallic thermometer is used in industry of two different metal expansion degree during temperature change the principle of work, its main component is a use two or more pieces of metal laminate composed of multilayer metal together, in order 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. This kind of instrument of temperature measurement range is - 50 ~ 550 ℃, the precision of the commonly used is 1. Level 0 and 1. Level 5. Is it used for industrial thermometer with a glass rod and similar, but can be used under the condition of higher mechanical strength. Mercury thermometer, is a kind of expansion type thermometer, mercury freezing point is - 39 ℃, the boiling point is 356. 7 ℃, temperature range is - 39° C— 357° C, it can only serve as on-site monitoring instrument. Use it to measure temperature, not only simple and intuitive, but also can avoid external remote transmission error of the thermometer.