Cutless bearings refer to rubber lined bearings operating with water lubrication on an elasto-hydrodynamic principle. The fluted design of the bearing utilizes basis lubrication principles to allow formation of hydrodynamic water wedges at the bearing surfaces by flow of water from the grooves.
Cutless bearings have a wide spectrum of marine applications, which include propeller shaft bearings in stern tubes or struts, rudder bearings and cutter bearings, in a variety of craft. Besides marine applications, cutless bearings are also used in hydroelectric turbines, centrifugal pumps and other water submersible devices.
When used in propeller shaft housing, the cutless bearing provides a structural support with built-in resilience that allows the bearing to yield in sympathy with the bending of the boats structure and thus prevents shaft bearing misalignment or shaft wear. These abrasive particles do not embed into the bearing surface and cause little cutting and wearing of the shaft.