What is the function of a thermowell in a liquid thermometer system?

A thermowell serves primarily as a protective barrier between the thermometer and the liquid it is measuring. In a liquid thermometer system, the thermowell is inserted into the liquid and acts as a sheath that encases the sensing element of the thermometer. This design protects the thermometer from potential damage that can occur from the harsh conditions of the process, such as high pressure, corrosive materials, or mechanical impact.

By using a thermowell, the integrity and functionality of the thermometer are preserved, which allows for accurate and reliable temperature measurements over time. This is especially crucial in environments where frequent maintenance or replacements would be disruptive or costly. Additionally, thermowells can be designed to allow for easy replacement of thermometers without interrupting the process flow, further highlighting their protective and practical utility in liquid temperature measurement systems.