Correct option is C
Crankshafts primarily use
plain bearings (also known as journal bearings or sleeve bearings) for supporting rotational motion. These bearings are made of a soft metal alloy (commonly called babbitt) that reduces friction and accommodates slight misalignments. The crankshaft journal rests on the bearing surface, and an oil film forms a lubricating layer to prevent direct metal-to-metal contact.
This bearing is used in high-load applications like crankshafts due to their ability to handle large radial loads.
Construction: Comprises an inner sleeve and an outer housing, with a lubricating oil film forming a hydrodynamic wedge.
Hydrodynamic Lubrication: Oil is continuously supplied to the bearing, creating a pressurized film that supports the rotating crankshaft.
Wear Resistance: Plain bearings are resistant to wear and can endure high rotational speeds.
Materials: Common materials include babbitt metal, bronze, and aluminum alloys for durability.
Cooling: Engine oil flowing through the bearing helps dissipate heat generated by friction.
