Time：2020.01.01 Source：Roller Bearings Suppliers
Self-aligning ball bearings are double row bearings with spherical outer ring raceways. Its inner ring, ball, and cage can rotate freely around the center of the bearing and have self-aligning properties. Its self-aligning ability can compensate for alignment errors, shaft deformation, and bearing seat deformation.
The bearings are suitable for transmission bearings, in which the shaft and the upper shell are difficult to center, and the shaft is prone to deflection. Self-aligning ball bearings are able to support axial and radial loads in both directions.
Self-aligning ball bearings were invented by SKF. This SKF bearing has two rows of balls and a common concave spherical raceway on the outer ring.
There are several designs of self-aligning ball bearings manufactured by SKF. They are the basic design of open bearings, sealed bearings, and open bearings.
Structure of self-aligning ball bearings:
Self-aligning ball bearings have two types of structure: cylindrical hole and conical hole. The material of the cage is steel plate, synthetic resin, etc. The characteristic is the outer ring raceway is spherical, with self-alignment, which can compensate for errors caused by different heart degrees and shaft deflections. Still, the relative inclination of the inner and outer rings must not exceed 3 degrees.
Self-aligning roller bearings can support radial loads and axial loads in two directions — large radial load capacity, which is suitable for heavy load and impact load. The inner diameter of the inner ring is a bearing with a tapered bore, which can be directly installed. Or use an adapter sleeve and a disassembly cylinder for installation on a cylindrical shaft. The cage is made of a steel sheet pressed cage, a polyamide formed cage and a copper alloy car cage.
Feature of self-aligning ball bearings:
Self-aligning ball bearings mainly bear radial loads and can withstand small axial loads. The axial displacement of the shaft (housing) is limited to the clearance limit, and it has self-aligning performance, allowing regular work under the condition that the inner and outer sides are relatively inclined. It is suitable for parts where the support seat hole cannot strictly guarantee coaxiality.
The bearings are self-aligning and are not affected by misalignment of the shaft relative to the bearing housing. It is particularly suitable for bearing applications where considerable shaft deflection or misalignment is possible. In addition, SKF self-aligning ball bearings have the lowest friction among all rolling bearings, so that they can maintain a low temperature even at high speeds.
SKF self-aligning ball bearings are also available with seals with contact seals on both sides of the bearing – designation suffix 2RS1. These sheet steel reinforced seals are made of oil- and abrasion-resistant acrylonitrile-butadiene rubber (NBR rubber). These seals allow operating temperatures ranging from -40 ° C to + 100 ° C, as well as temperatures up to + 120 ° C for a short period of time.
The sealing lip touches a smooth chamfer on the inner ring with light pressure.
Self-aligning ball bearings with dust caps and seals are filled with an appropriate amount of grease during assembly. The bearings should not be heated or cleaned before installation, and need not be relubricated during use. They are suitable for operating temperatures between -30 ℃ and 120 ℃. Self-aligning ball bearings are mainly used for precision instruments, low-noise motors, automobiles, motorcycles, and general machinery. They are the most widely used bearings in the machinery industry.