Aluminum rolling mill rolls and roll bearings are important parts of the rolling mill. In rolling production,RollerDirect contact with rolled metal, resulting in plastic deformation of the metal. Therefore, the roll is the main deformation tool of the rolling mill, and the roll is supported by various bearings. The quality and service life of rolls and roll bearings are directly related to the product quality, production efficiency and production cost of the rolling mill. Therefore, the maintenance of the roller bearing is particularly important.

Working Characteristics of 1. Roller Bearings

Roll bearings are used to support the rolls. Compared with general bearings, roll bearings have the following characteristics:

1. Strong pressure bearing capacity. Due to the limitation of the overall size of the bearing seat, it cannot be larger than the smaller diameter of the roller body, and the length of the roll neck is shorter, and the unit load on the bearing is larger. The unit pressure of the general roller bearing is as high as 2000 ~ 4800Mpa, which is 2~5 times that of the ordinary bearing, and the PV value (the product of the unit pressure and the linear velocity) is 3~20 times that of the ordinary bearing.

2. The speed difference is large. The operating speed of different rolling mills varies greatly. For example, the export speed of modern six-stand cold rolling mill has reached 42 m/s, the export speed of high-speed wire rod mill has reached 100 m/s, while the export speed of some low-speed rolling mills is only 0.2 m/s. Obviously, different types of bearings should be used for rolling mills with different speeds.

3. Poor working environment. When hot rolling,RollerApplication of water, sewage, oxide and other cooling. It is easy to fall into the bearing. The cold rolling mill uses process lubricants (emulsion, etc.) to lubricate and cool the rolls and rolled parts, and cannot be mixed with bearing lubricants. Therefore, the seal of the bearing put forward higher requirements.

Therefore, the requirements for roll bearings are large carrying capacity, low friction coefficient, impact resistance, and ability to work at different speeds. Structurally, the radial dimension should be as small as possible (so that a larger roll neck diameter can be used), with good lubrication and cooling conditions.

Maintenance of 2. Roller Bearings

Roller bearings need to be taken out of the mill regularly for inspection and maintenance to improve the service life of roller bearings. The frequency of bearing maintenance should be adjusted according to the operation of the rolling mill, mainly based on experience. The usual maintenance frequency is once every three months at full load, most rolling mills once every six months, and light rolling mills once a year in December. After the first 1000 hours of operation, the roller bearings should be disassembled and inspected. During operation, it is necessary to clean the bearing and check the oil seal. If necessary, replace the oil seal completely. If no abnormality is found, the interval of the secondary examination may be extended.

　　RollerThe general steps of bearing maintenance are: 1. Track and record the position of the bearing in the rolling mill. It is recommended to use a special record card for roller bearing maintenance services. It is also necessary to pay attention to special lifting methods and tools when removing the bearing from the bearing seat or inspecting the bearing. 2. Clean the bearing. During the cleaning of the bearing, all flaking, water, residual lubricant and any other dirt that can cause serious bearing wear should be removed. 3. Check the bearings, including visual inspection and minor repairs. Pay attention to check and repair the bearing seat, and put the bearing back into the bearing seat as needed. 4. Lubricate the bearing. The existing common rolling mill has the characteristics of large rolling force and high rolling speed, which requires the lubricant to have excellent viscosity-temperature performance, oxidation stability, rust resistance and wear resistance. Therefore, the lubricant with better performance should be selected as far as possible to lubricate and maintain the roll bearings.