What are the different types of gearbox bearings?

Different types of gearbox bearings are used for different purposes. They can be Needle bearings, Torrington bearings, Planet carrier bearings, and Compact aligning roller bearings.

Needle bearings
Needle bearings are widely used in planetary reducers and cage assembly bearings of hydraulic excavators. These bearings are subjected to heavy loads and extremely harsh operating conditions. The lubricating oil used to mount these bearings often mixes with abrasion powder. The planetary gear is particularly abrasive, and the long bearing operating life has been a recurring issue.

Needle bearings are available in single and double row designs and with either solid or split cage assemblies. Compared to single row bearings, needle rollers can handle larger shafts and have excellent rolling characteristics within their small cross sections. Generally, needle bearings are produced in drawn-cup designs because they are more economical than machined versions. Loose needle bearings are assembled between a hardened shaft and hardened end washers to provide axial location.

Planet carrier bearings
Using planet carrier bearings is an efficient way to reduce the number of lubricants required by gearboxes. The gears are placed in a helical arrangement and should be symmetric in their load distribution. To calculate the proper size of planet bearings, the maximum input torque must be determined. Moreover, the load distribution of planetary gears should be determined using the lead modification method on planetary stage gears.

Compact aligning roller bearings
Self-aligning ball bearings are double-row ball bearings that operate in a single spherical outer ring raceway. Their self-aligning feature compensates for mounting errors, deflections, and whipping forces of the outer ring and shaft. This design helps prevent misalignment and ensures that the gearbox bearings function as they should.

In gearbox applications, compact aligning roller bearings are single-row, non-locating roller bearings. These bearings benefit from their low cross-section and high radial load-carrying capacity, making them an excellent solution for heavily loaded shafts. They can reach over 30 percent greater load capacity than standard bearings and can be installed with a simple interference fit. These bearings are designed for a variety of different applications, from gearbox shafts to planetary gearboxes.