Selecting thermowells

New tool helps users select the right thermowell early in the design process

Emerson Process Management has introduced an online thermowell calculation tool that incorporates the new ASME PTC 19.3 TW standard. The tool is now available free-of-charge on their site. Emerson is the first to make available an online tool offering a more automated approach to thermowell calculation as opposed to the traditional way of utilising spreadsheets.

"The new tool offers preliminary calculations and gives users the option to perform a quick pass or fail thermowell calculation," according to Danjin Zulic, Temperature Marketing Engineer, Emerson Process Management. "Users can save time by performing iterative, preliminary calculations to select the right thermowell earlier in the design process."

In addition to the tool, the web site has a link to an R21 Report request form for official evaluations. "Once the thermowell order is ready to be placed, the official R21 report provides detailed documentation of the thermowell calculation."

A video and white paper are also available on the web site that explains the new ASME PTC 19.3 TW standard. Enhancements in the new standards and thermowell calculation tool include different types of stem profiles, more accurate natural frequency equations, and a calculated Strouhal number. The new standard also provides natural frequency correction factors that take into account different components of the thermowell such as the mounting style and temperature sensor mass.

• Emerson's Jim Cahill has also written on this in his Emerson Process Experts Blog: Online Calculation Tool for Thermowell Installations