The tubesheet is not gasketed on both sides. It's used as a flange too.
Construction:
- shell
- flange
- gasket
- tubesheet

The tubesheet has a bolted channel, but this channel is smaller than the actual shell. That's why I find it not OK to model it as a 2-sided gasketed tubesheet. There will be bending stresses due to bolt forces too.
I want the in practice bolted channel modelled as a normal channel on the outside of the tubesheet (configuration e). Maybe a little less stiff cause of the difference in connection. I can't seem to find a correct way to model the channel though. I can model the tubesheet using the tubesheet input screen and choose configuration e there, but how do I set the size of the channel (which is the measurement for the area where the difference in pressure is).