- Radial ball bearings are designed to support radial loads, which are forces acting perpendicular to the shaft's axis. They are commonly used in applications where the primary load is radial, such as in electric motors, pumps, and gearboxes.

   - Spherical Roller Bearings: Spherical roller bearings are well-suited for applications where heavy radial loads, shock loads, and moderate axial loads are present, and where misalignment accommodation is required.

In summary, main bearings are primarily responsible for supporting the rotational motion of the crankshaft and withstanding radial loads, while thrust bearings are designed to counteract axial forces and maintain the axial position of the crankshaft. Both types of bearings play critical roles in ensuring the smooth and reliable operation of engines and machinery.