SCH_RATE is basically the wall thickness of pipe&fittings. The example doesn't work properly in the 3D model, when you switch the pipeline, it changes automatically which is correct. The Pipeline changes from SCH_RATE=120 & SIZE=2 to SCH_RATE=140 & SIZE=2. but the fitting is not replaced.
The fitting should also be replaced because it has another wall thickness which is related to the SCH_RATE.
This is a major concern and I think this needs to be updated to work properly.
There is a PTC case that I created for this issue: C12433195