Definition - What does Thermowell mean?
A thermowell is a closed-end tube that transmits temperature information from a remote location to an analog or digital device while protecting the instrument from harsh environmental factors, flows or pressure variations.
Corrosionpedia explains Thermowell
Thermowells are generally used for applications that require precise temperature readings and possess a threat such as corrosion, high pressure or shear forces. Therefore, the correct thermowell metal must be selected according to the environmental conditions where it will be used.
There are three main types of thermowells: threaded, socket weld and flange welded.