Horizontal Motors: Application Of Angular Contact Ball Bearings

Angular contact ball bearings can also be adopted in horizontal motors when necessary, and they are not exclusively applicable to vertical motors. Vertical motors utilize angular contact ball bearings mainly to bear the axial force generated by the self-weight of the rotor. Although such equipment is free from continuous axial load caused by rotor self-weight, the application of angular contact ball bearings is a common and mature design solution when the motors are subjected to operational axial thrust, require precise axial positioning, or pursue high rigidity and high-speed performance.

In horizontal motors, angular contact ball bearings are rarely used alone. They are mostly installed in pairs in back-to-back or face-to-face arrangements to withstand bidirectional axial loads and improve operational rigidity. Another widely adopted structural configuration equips the positioning end with an angular contact ball bearing and the floating end with a deep groove ball bearing or cylindrical roller bearing. This structure can effectively limit rotor axial play and compensate for thermal elongation of the motor shaft. Compared with deep groove ball bearings, angular contact ball bearings can better bear loads such as fan suction and pump axial thrust. With reasonable preloading and standardized installation, they can operate stably in horizontal structures while ensuring the precision and reliability of motors.

The adoption of angular contact ball bearings in motors delivers significant improvements in performance and working condition adaptability compared with deep groove ball bearings, but it also imposes higher requirements on design, assembly and service conditions.

Angular contact ball bearings can bear both radial loads and unidirectional or bidirectional axial loads, and can accurately limit rotor axial play. They are especially suitable for horizontal motors with axial force loads, such as fan motors, pump motors and gear-driven motors. Featuring higher rigidity and better operational precision, they exhibit superior stability over ordinary deep groove ball bearings under high-speed working conditions, which helps reduce vibration and noise and improve the operational stability of motors. Paired angular contact bearings can also withstand overturning moments, making them suitable for scenarios with fluctuating loads or high coaxiality requirements. Meanwhile, they have generally better service life and load-bearing capacity, which effectively improves the overall reliability and durability of the complete machine.

Nevertheless, angular contact ball bearings usually require paired installation and reasonable preload setting. Improper installation direction and preload control may lead to overheating, abnormal noise and even early failure, placing higher demands on machining accuracy and assembly processes. A single angular contact bearing can only bear unidirectional axial force and must be matched with paired bearings or positioning structures, resulting in a relatively complex structural design. In addition, they are more costly than deep groove ball bearings of the same specification and are more sensitive to lubrication conditions and alignment. Misalignment or insufficient lubrication will easily cause bearing failures. In general, angular contact ball bearings are more suitable for motors with high requirements for rigidity, precision and axial load capacity, while deep groove ball bearings are more economical and practical for ordinary light-load, low-speed and low-cost application scenarios.