Imagine I have a simple square block made into a pipe threaded elbow.  In the right face and the top face, I drill a hole to intersect one other and thread the ends.  If I want to analyze just the PART, I can "fix" the bottom face and apply pressure to the holes.  I will get a resultant net force trying to push the block to the left.  FBD would makes this obvious.  So in reality the part doesn't go flying off because the area is counter-balanced down stream by the connecting hydraulic hoses.  So how do you like to model this sort of thing correctly?  We toy'ed with modeling a fake plug in the ports but that un-realistically stiffens the port.  We tried adding a net axial force on the port to counter-act the pressure force but that was clunky and not super accurate.  I'm really hoping there is a special SW tool that I just haven't found yet for these sorts of areas.  Any ideas/ suggestions would be appreciated!  Thanks!