RollerThe bearing mill is developed on the basis of replacing the bearing bush used before. Compared with the bearing mill, its stability has been greatly improved. At present, my country's rolling mills need to widely use bearings to replace bearing bushes, but it is found that roll bearings often fail during use, which will have a great impact on production. According to statistics, the main factors that cause the failure of the roller shaft are: assembly influence, improper lubrication influence, improper protection of foreign matter and overload. The following will analyze the causes of roll bearing failure and introduce measures to reduce roll bearing failure.

1. Failure caused by improper assembly of roll bearing

One end of the roll bearing is composed of a four-row radial short column roll bearing and a single-row radial ball bearing. In the steel rolling production process, the radial force is mainly the main rolling force and the radial force generated during the rolling process, and the axial force generated during the rolling process. The radial force is shared by the two bearings, and the axial force is mainly borne by the single row radial bearing. Through analysis, it is found that this bearing distribution method has high carrying capacity, bearing size is smaller than other bearing methods, and shaft positioning is more accurate. In particular, the four-row short cylindrical bearings have high centering performance and high manufacturing accuracy.

After consulting the bearing manual, it is found that the bearing clearance is less than 0.25mm, which can meet the requirements of multiple disassembly. It was discovered after disintegration,RollerThe bearing uses a threaded half ring and a lock nut to fix the inner ring of the bearing, and the bearing end cover is used to compress the outer ring of the bearing to ensure that the roller will not move axially. According to statistics, when the bearing end cover is not compressed and the bearing moves in the bearing seat, it will have a great impact on the product quality during the rolling process, and the requirements cannot be met during the rolling process. On the contrary, when the bearing end cover is pressed too tightly, the bearing axial clearance is too small and the bearing preload is too large, which causes the radial ball bearing outer ring to move axially to a certain extent, thereby eliminating a certain clearance of the bearing. When the preload exceeds a certain range, in addition to the clearance of the bearing itself has been eliminated, the ball of the radial ball bearing will be offset from the raceway, resulting in accelerated wear of the bearing. When the bearing rotates at high speed, the overheating of the bearing will cause the bearing to expand and deform, which will easily cause the bearing to burn. Excessive preload will also cause the bearing to jam. Therefore, when assembling the bearing, it is necessary to control the amount of press-in and retain a certain amount of heat. According to statistics, when the dial indicator measured the assembled roll bearing clearance between 0.15~0.25mm, the bearing use time is longer.

2. Influence caused by improper lubrication of roll bearing

Good lubrication will greatly improveRollerThe service life of the bearing. Lubrication is achieved through the use of lubricants. By using lubricants to improve the friction state of the friction pair, reduce friction resistance and slow down wear. During the operation of roller bearings, there are both flow friction and sliding friction. The roll body of the bearing is made of very hard bearing steel. When moving under force, it is only necessary to maintain a certain oil film between the inner ring and the outer ring of the bearing. However, in actual work, it is found that many bearing damages are caused by the deterioration of bearing lubrication performance. The factors leading to deterioration of lubrication are as follows:

(1) improper lubrication method.

(2) The lubrication pipeline is improperly arranged and the oil circuit is blocked.

(3) improper selection of lubricating oil.

(4) The amount of lubricating oil cannot meet the lubrication demand. At present, the lubricating oil used in rolling mill bearings has a high oil absorption capacity, which forms a certain strength oil film during work. However, studies have found that grease lubrication has a better lubrication effect than oil lubrication.