Hello,

please remember,
the full force from pressure thrust don't act on the nozzle of the pump. The force from pressure acts on the inside area of the pump and indicates a horizontal force and a moment on the anchor of the pump.
The nozzle of the pump is nearly free from forces because of the expansion joint in front of the nozzle.
At the nozzle acts only a horizontal force from the inside pressure and the "ring-area" of the bellows (Outsidediameter of bellow - Insidediameter of bellow). In the other direction the forces act on the end of the pipe (bend) and so on the Fixpoint besides the expansion joint.

If you use an expansion joint with tie rods, then the forces from pressure stay in the expansion joint and the tie rods.
But ... if you have some thermal expansion between fixpoint and pump then the tie rods dont't fit closely and the full pressure thrust acts again on the body of the pump.

The problem of expansion joints with fixpoints in front of a pump nozzle should be coordinated with the manufacturer of the pump.