This video covers the common types of thermowell process connections. The styles are referred to by what their process connection is.
The types are threaded thermowell, a flanged thermowell, a welded or weld-in thermowell, and a sanitary thermowell.
Threaded thermowells are commonly used when thermowell removal occurs infrequently. These wells are typically threaded into a welded fitting widely referred to as a weldolet on the pipe or vessel. Typical installations include smaller pipes or vessels where corrosion is not an issue.
Flanged thermowells are the preferred well for applications that require frequent removal or replacement due to corrosion or other hazards. Flanged wells will bolt to a mating flange installed on the process piping. Typical installations include large pipes with high pressure and high corrosion.
Weld-in thermowells are welded directly to the pipe or tank and provide a high-quality connection. Because being welded in, their removal is not easy, and they should only be installed when quick access is not required, and corrosion is not an issue. Typical installations include very high temperature and high-pressure applications, for example, a steam line or other non-corrosive applications.
Sanitary thermowells are generally fitted with a Tri-clamp or other clean-in-place connection. These thermowells also have a smooth surface which allows for easy cleaning and prevents contamination of the process: typical installations include dairy, food processing, and pharmaceutical industries.
