Spherical Roller Bearing
Spherical roller bearings are double row inseparable bearings. Their structure includes a solid outer ring with a spherical raceway, a solid inner ring and a drum roller with a cage. The inner ring has a cylindrical hole or a tapered hole. The symmetrical drum rollers can be freely adjusted in the outer spherical raceway. This makes it possible to compensate for shaft bending and mating surface misalignment.
Aligning Ball Bearings
The self-aligning ball bearing is a double-row ball bearing with an outer ring raceway processed into a spherical shape and an inner ring with two deep groove raceways. It has self-aligning performance and is a non-separable bearing. It is mainly used to bear radial load. While bearing radial load, it can also bear a small amount of axial load, but generally cannot bear pure axial load, and its limit speed is lower than that of deep groove ball bearings.
The similarities between spherical roller bearings and spherical ball bearings:
Both have automatic self-aligning functions and are double-row rolling elements.
The difference between spherical roller bearings and spherical ball bearings:
1. The rolling elements have different shapes. The rolling elements of spherical roller bearings are rollers, and the rolling elements of spherical ball bearings are balls.
2. Different bearing capacities. Aligning ball bearings mainly bear radial load. While bearing radial load, they can also bear a small amount of axial load, but generally cannot bear pure axial load. The rated load ratio is 0.6~0.9. Spherical roller bearings mainly bear radial loads and can also bear a certain axial load. The rated load ratio is 1.8~4.0.
3. The use environment is different. The bearing capacity of spherical roller bearings is greater than that of self-aligning ball bearings. They are suitable for low-speed and heavy-load working conditions, while self-aligning ball bearings are suitable for high-speed and light-load working conditions.
Factors to consider when selecting spherical ball bearings and spherical roller bearings:
1. Allow space
That is, the external parameters that allow the installation of bearings;
2. Load size and direction
There are both radial and axial combined loads, as well as large deformation of the shaft or housing and poor installation alignment. Aligning ball bearings or spherical roller bearings can be used.
3. Working speed of bearings
Spherical roller bearings are suitable for heavy loads and medium speeds, and self-aligning ball bearings are suitable for light loads and high speeds;
4. Rotation accuracy
Generally, G-level precision bearings can be used
5. Generally, the rigidity of roller bearings is greater than that of ball bearings. The rigidity of the bearings can be improved by preloading, but it must be appropriate;
6. Friction torque
Generally speaking, when carrying low friction torque, self-aligning ball bearings should be used as much as possible.
7. Installation and disassembly
When disassembly is frequent, spherical roller bearings or spherical ball bearings with a tapered inner ring and an adapter sleeve or withdrawal sleeve can be used.