What is the cause of the bimetallic thermometer calibration often?

Bimetallic thermometer is a kind of measuring instrument in the field of low temperature detection, working principle is different according to constitute the bimetallic thermometer the distortion degree of the piece of metal to judge some of the material temperature, it can be directly measured various - in the process of production 80 ℃ ~ + 500 ℃ temperature range of liquid, steam and gas medium. In the textile industry, the bimetallic thermometer is a kind of simple measuring sensors, is an indispensable textile instrument. Equipment in use process could not go wrong, will certainly be produced in the process of using falloff. Instrument misalignment will lead to the test result error, and is likely to cause a series of losses. In order to avoid this kind of situation, must be regularly for textile instruments such as bimetallic thermometer for metrological verification or calibration, ensure the accuracy of its value. Regular calibration instrument has become many industry regulation, the related department also issued relevant provisions of the state, such as the original textile department from 1985 to 1995, successively issued 69 textile instrument metrological verification procedures. Hope that through these procedures, the standard in the industry of instruments use behavior. These rules of condensing the textile worker's wisdom and experience, of measurement to promote textile instrument scientific, standardized management and the textile testing work smoothly plays a very important role.