dont get confused by term journal bearing. any bearing that
supports a shaft laterally is journal bearing.
anti friction bearings are of two major types:-
roller and ball bearing. the balls or cylinders contact area
bears the load. they are used up to DN number ( dia in mm
multiplied with rpm ) 5,00,000. above that hydrodynamic
bearings that use oil film to support load are used. Note
that journal bearing can be anti friction or hydrodynamic.
journal bearings support shaft laterally and take care of
lateral vibration. thrust bearings support shaft axially and
take care of axial displacement ( float).
oh, i am sorry, antifriction bearings cant be journal bearing.
and the other two classifications are :- radial bearing and
up to DN number 500000, antifriction bearings are used,
after that hydrodynamic bearings are used.