During the operation of the bearing, the retainer must withstand stress caused by friction, impact, centrifugal force, and inertial force. They may also be chemically affected by certain organic solvents or coolants, lubricants, and lubricating additives. Therefore, the cage is easily damaged. Below, Fuhai He's editor will explain the reasons for abnormal heating of the lower bearing and cage damage:

(1) The coaxiality of the bearing seat hole, the stiffness of the seat hole wall, and the strength and sequence of tightening bolts can all cause deformation of the bearing seat hole and bearing, leading to abnormal heating and vibration, causing irregular vibration impact, compression, uneven wear, and even fracture of the cage.

(2) Due to the misalignment of the tape wheels, the shaft is subjected to additional axial force, while the self-aligning ball bearing installed on the optical shaft is not suitable for bearing axial force, resulting in abnormal temperature rise of the bearing and accelerated wear of the cage.

(3) When assembling and adjusting the inner cone sleeve, the temperature rises from 30 ℃ before changing the tape to 43 ℃, and then drops below 40 ℃ after a week.

(4) The reason for the high bearing temperature is not only related to the assembly quality, but also directly related to the cleanliness, quality, variety, and viscosity of the oil (grease), especially high speed bearings are more sensitive to the viscosity of the oil. For example, the room fan has a high speed, small air volume, high air pressure and small torque. It is reasonable to use thin oil for equipment and bearings with high speed and light load. Because of the high speed, it is easy to form a bearing oil film, reduce the friction resistance of rolling elements, and facilitate cleaning and heat dissipation. However, the bearing box of No. 1 fan has used N320 medium load process Gear oil since it was put into production. After the problem was raised, it was changed to N22O, but the viscosity is still large. It would be better if it could be changed to HJ20HJ3012, The temperature will also drop from around 60 ℃ for a long time.

(5) Due to the lack of oil drainage holes in the bearing seat, excess oil can only be squeezed out of the journal, and the refueling interval is short. Although not much is injected each time, the oil chamber quickly fills up, causing a sudden increase in the bearing operating temperature of 25-35 ℃. This is the reason for the sudden increase in bearing temperature during normal operation. This situation continues for several days and improves with the extrusion of oil. Prolonged repetition not only wastes and affects the bearing life, but also increases the difficulty of fault diagnosis. Due to the increase in bearing temperature, the rolling contact stress increases, the viscosity and adsorption of grease decrease, and wear increases; In addition, due to the temperature of the bearing ring being higher than adjacent parts such as the cone sleeve, thermal expansion may cause loose fits that were not too tight. The temperature rise caused by excessive oil and the temperature rise caused by loose sleeves are difficult to distinguish at the beginning, and sometimes the impact of thermal expansion causes both to exist simultaneously. In short, repeated results will inevitably make the hole and shaft fit tend to loosen. This situation often occurs mainly due to inadequate lubrication regulations, and at the same time, the operator also has the idea of "more than less" when refueling. It is not necessary to frequently refuel in a closed oil chamber, as long as there is oil in the raceway, normal operation will not cause a shortage of oil fault. In addition, oil drain holes can also be installed at appropriate positions on the bearing seat to facilitate regular refueling and avoid the phenomenon of temperature rising for several days each time.

(6) Too much tension on the tape can also increase the temperature of the bearing, intensify vibration, and make the tape more susceptible to damage. Due to the increase in radial load of the bearing, elastic deformation occurs at the contact between the rolling element and the raceway, increasing frictional heat and wear, and easily causing pitting corrosion.

(7) Abnormal vibration or shaft bending of the fan often causes rapid temperature rise and easy damage to the bearings. 2. Abnormal bearing is related to misunderstanding. For a long time, the working temperature of bearings has similar provisions in almost all equipment technical documents. Some people have misconceptions and misunderstandings about the issue of bearing temperature rise. I have encountered this situation in several factories. In many technical documents, it is stipulated that the working temperature rise of bearings shall not exceed 30 ℃, 40 ℃, or 65 ℃, 75 ℃, 80 ℃, and 90 ℃ without distinction or distinction between equipment objects.

Regular maintenance and upkeep should be carried out during the use of the cage to extend its service life!