Bimetallic strip works on the principle of co-effiecient of thermal expansion.This content describes the working principle and advantages/disadvantages of bi-metallic strips as temperature indicators.
Working principles Bimetallic strip
A bi-metallic strip consists of two different metals joined together. It bends when exposed to temperature changes due to the differing rates of thermal expansion of the metals. This bending is used to deflect a pointer over a calibrated scale to indicate temperature.
Advantages of bi-metallic strips include low cost. Durability, ease of installation and maintenance. Good accuracy relative to cost, and a fairly wide temperature range.
However, they have limitations in terms of mounting options, are typically only used for indicating temperature.And may experience calibration changes if handled roughly. Their accuracy is also not as high as glass stem thermometers.
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