I am not an expert, but I think you have to know the following:

1. The Piping Code you are using,
2. The appropriate flexibility factors for a cladded pipe & fittings,
3. The appropriate Stress Intensification Factor for a cladded pipe & fittings,
4. The appropriate equivalent modulus of elasticity for the composite material,
5. The appropriate equivalent coefficient of thermal expansion for the composite material,
6. The allowable stresses for the composite material,
7. The expansion joint you are using (there are tied expansion joints allowing axial movement, i.e. nuts on one side only)
8. How to model your expansion joint properly (read the CAESAR manuals)
9. The dos and donts when using expansion joints (read EJ manufacturer manuals)

I usually compare the operating loads with the allowable equipment loads.
The tie rods will take care of the thrust force, there should be no thrust force acting on your nozzle.
You should consider the possibility of buckling due to external pressure.
You should also consider the need of using stiffening rings to prevent pipe ovalization.
You should also consider the radial thermal expansion of the pipe.


I still have no experience with that kind of pipe, so let us wait for our teachers to give us a hand & often to correct us with our mistakes.

Hope this helps,