A: 

The advantages of needle roller bearings:

1. The friction resistance is small, the power consumption is small, the mechanical efficiency is high, and it is easy to start.

2. The size is standardized, interchangeable, easy to install and remove, and easy to maintain.

3. Compact structure, light weight, and reduced axial size. High precision, high speed, low wear and long service life.

4. Some bearings have self-aligning performance, which is suitable for mass production, with stable and reliable quality and high production efficiency.

5. The transmission friction torque is much lower than that of hydrodynamic bearings, so the friction temperature rise and power consumption are lower;

6. The starting friction torque is only slightly higher than the rotating friction torque;

7. The sensitivity of bearing deformation to load changes is less than that of hydrodynamic bearings;

8. Only a small amount of lubricant is needed for normal operation, and it can provide lubricant for a long time during operation;

9. The axial size is smaller than the traditional hydrodynamic bearing;

10. It can bear combined radial and thrust loads at the same time;

11. In a large load-speed range, the unique design can obtain excellent performance;

12. Bearing performance is relatively insensitive to fluctuations in load, speed and operating speed.