Journal bearings provide radial support for the rotating equipment and thrust bearings provide axial positioning for them. Ball and roller bearings are used in some aircraft jet engines. However, all industrial gas turbines use journal bearings.
Journal bearings can be split or full-round. Large-size bearings used for heavy machinery normally have heavy lining. Precision insert-type bearings used commonly in internal combustion engines have a thin lining. The majority of sleeve bearings are of the split type for convenience in maintenance and replacement.