Bimetallic thermometer in low temperature and what is the use of high temperature category mistake?

Bimetallic thermometer is a kind of field detection instrument of high temperature measurement, in many industries are bound to use. Bimetallic thermometer in the process of application also poses a misunderstanding, the misunderstanding will seriously affect the application of the bimetallic thermometer. So what are detailed error? Bimetallic thermometer is used two different temperature contraction coefficient of metal, and made into a thermal sensor, adequate application of the heat bilges cold everybody understands the reason, handle in WenJinCheng measuring temperature accuracy, in order to measure the bimetallic thermometer acuity, everyday will be made of metal spiral coil shape, when multi-layer metal temperature changes, the layers of metal contraction or compression quantity, makes the spiral coil rolled up or let go, because the one end of the spiral coil and are connected with a can freely move the pointer to the other end. Therefore, when the temperature of the bimetallic strip touch changes, Pointers can be on a circular dividing scale showing the temperature, the bimetallic thermometer WenFanChou is - Deviation: 40 ~ 550 ℃, promise & plusmn; 1. 6 degrees. This form the following two kind of erroneous zone: 1, category WenFanChou bimetallic thermometer measured at low temperature is 200 ~ 650 ℃, promised to deviation are the scale range of less than 1%. True this is wrong, because, this made spiral coil shape metal thermal sensors, in 650 ℃ low temperature circumstances easily fatigue, temperature difference is very apparent, with is that when the temperature above 550 ℃, consider using thermocouple to measure. 2. Category of the highest temperature in some records show that the bimetallic thermometer WenFanChou measurement is 200 ~ 650 ℃ ( This is not accurate) The highest temperature, can test to 650 ℃. This is rare, bimetallic thermometer temperature up to 550 degrees in the production process, so that we in use process should be used according to the actual situation.