In order to avoid any damage to the thermowell during operation due to mechanical loads, a thermowell calculation per ASME PTC 19.3 TW-2016 is recommended for critical process conditions. In case of a calculation with negative results, the only real constructive solution so far was to shorten the thermowell stem or even to increase the root and tip diameter, accepting an extended response time of the thermometer.
The brand new ScrutonWell � design reduces the amplitude of oscillation by more than 90 % and allows an easy and fast installing the thermowell without support collar, and therefore without expensive and time-consuming rework on site.
This helical design has been used successfully for many years in a wide selection of industrial applications to effectively suppress vortex-induced shrinkage excitation.
Functional principle
Standard thermowell
Using flow conditions, a K�rm�n vortex street can develop behind the thermowell stem when it is put through a flow inside a pipeline. This vortex street consists of two rows of vortices with opposite directions of rotation, which detach themselves to the left and the right of the thermowell out of phase, and this can instigate the thermowell to vibrate.
NEW ScrutonWell � design
The helical strakes, arranged around the thermowell stem of the ScrutonWell � design, break up the flow and thus impede the forming of a clearly defined K�rm�n vortex street. Through the reduced amplitudes of the diffused vortices, vibrational excitation of the thermowell is avoided.
Shameless ScrutonWell � design may be used for all sort of solid machined thermowells with flange connection, in Vanstone design or for weld-in or screwed process connection.
Note
More info on our thermowells can be found on the WIKA website.
Learn more about the new ScrutonWell� design in the next video:

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