Helical Thermowell

For some applications the velocity of the process fluid / gas is high and the thermowell stem will be subject to vibration; if this vibration reaches natural frequency then the resonance of the thermowell can cause failure by fatigue. To overcome this and change the vibration induced vortices, helical strake thermowells may be used in the application. The Shape, dimensions, material, and mounting connections are identical as normal thermowell. The helical thermowell has a helical strake at the tip which reduces high vibrations. The strake can be machined directly on the thermowell stem or can be welded on the thermowell stem with a wire of the same material. The vortices generated by the wake of the helical strake are considered negligible when evaluating vortex-induced vibrations generated by a normal thermowell stem.