The best way to solve the problem of linear shaft failure is to avoid failure. This can be achieved by considering key performance characteristics during the selection process. These characteristics include noise, starting and running torque, stiffness, non-repetitive runout, and radial and axial play.

Torque requirements are determined by lubricant, cage, bearing ring quality (roundness of curved parts and surface finish quality) and whether a seal or shield is used. The viscosity of the lubricant must be chosen carefully, as unsuitable lubricants can generate excessive torque, especially in small bearings. In addition, the noise characteristics of different lubricants are also different. For example, grease produces a little more noise than oil. Therefore, lubricants should be selected according to their different uses.

During bearing rotation, if a random eccentric toe exists between the inner and outer rings, non-repetitive runout (NRR) very similar to cam motion occurs. The dimensional error of the cage and the eccentricity of the bearing ring and the ball can cause NRR. Unlike repetitive runouts, NRR has no way to compensate.

In the industry, bearings of different types and accuracy grades are generally selected according to the specific application. For example, when minimum runout is required, the non-repetitive runout of the bearing cannot exceed 0.3 microns. Likewise, machine tool spindles can only tolerate minimal runout to ensure cutting accuracy. Therefore, bearings with less non-repetitive runout should be used in machine tool applications.

In many industrial products, contamination is unavoidable, so seals or shields are often used to protect bearings from dust or dirt. However, due to the movement of the inner and outer rings of the bearing, the sealing of the bearing cannot be perfect, so the leakage and pollution of lubricating oil is always an unsolved problem.

Once the bearing is contaminated, the lubricant will deteriorate and the operating noise will also become louder. If the bearing overheats, it will seize. When contamination is between the balls and the bearing ring, it acts like abrasive particles between the metal surfaces, causing the bearing to lose its price. Using seals and shields to keep out dirt is one way to control contamination.

Ningbo Shitai Precision Machinery Co., Ltd. is a linear shaft factory and a spindle shaft factory, welcome to visit our official website.