expander suction nozzle as resolution point - Y/N ?

In steam turbine, exhaust is considered force resolution point, having zero co ord in NEMA SM23 calc in Caesar-II.

In centrifugal compressor, suction nozzle of largest dia - is considered force resolution point, having zero co ord in API-617 calc in Caesar-II.

Is expander, alike steam turbine and exhaust nozzle be the load resolution point.

In our case, we have a reducer at expander suction and both suction and discharge nozzles at terminal points have same diameter.

Isn't the lower pressure end be the resolution point for external load chk for 3X NEMA23 allowable from expander vendor!
reg,
sam