Having casually passed this topic a number of times, I've come across the first time I need to actually model it.

The documentation indicates the load case setup requires using a CS variable (as well as modify it by 2/3 and 4/3), but I'm not sure I see a location to input cold spring to cause this CS variable to appear.

Notionally, I'd expect I could use our favorite linear thermal expansion equation to back out a dummy element length and temperature and turn it rigid, and set temperatures to all else to 70F, and use this
the neutral temperature case.

But I wanted to make sure that I'm not missing something that's obvious.

It's easier to use the cold spring materials (#18 and #19) for the cold spring element. One is cut-long the other is cut-short.

Make sure you change the material back to the piping material on the following element.