hi,
you can alternate try this method
use WRC 107
select local loading method
take vessel dia= 1.8 Dia of vessel ( this is done to convert Cyllindrical vessel to sperical shape considering crown radius 0.9 D )
P= axial force
calculated Resulatant of VL and Vc == put in either in Vl or in VC
if you put resultant value in Vl=Vr then Vc=0
now calculate resultant of Ml and MC
put Mr in Ml=o and MC= MR
by this way you can get closer result.
this is my understanding
correct me if i am wrong!!