The service life of the cardan shaft of the hot-lock generator set is important for the smooth operation of the entire extruder drive system, and is a key component of reducing shutdown time, increasing productivity, and ensuring continuous production.

The hot mill consists of three parts: rough rolling, middle rolling and finishing tying. Take the rough rolling link as an example, in which the rough extruder universal shaft is used in the rough rolling main transmission system of the core components, located in the middle of the main motor and the rough roll, all the normal operation of the motor output torque to the roll, and then the temperature to 1300 degrees above the slab extrusion deformation, output the rolling link required thin thick steel plate.

Because of the special working conditions of the rolling office environment, there are not only very high working temperatures, but also cooling circulating water and site dust erosion of each component of the cardan shaft. When the drive system runs for a long time, the specifications between the flat shaft head of the roll and the flat head of the cardan shaft sleeve will expand. Under such conditions, the radial constraint of the flat head hole on the roller at work will be reduced, which will cause the flat head cover to cause the left and right swing of the radial force not the same, endangering the reliability of the whole transmission system.

For the carbanding of the final two positions, because the speed is generally above 920 RPM, it is more necessary to raise the mutual clearance between the roller sleeve and the roll head. If the mutual clearance is not adjusted immediately, it will cause vibration to the whole transmission system, which will not only destroy the service life of the cross shaft of the cardan shaft, but also continue to greatly reduce the service life of the rolling mill bearing. If the problem is not found immediately, it is very easy to brew a major safety accident.

Therefore, at the beginning of the design scheme should take into account the flat sleeve specifications of the cardan shaft and the flat head specifications of the roll, the flat head clearance is generally 0.05mm-0. In the middle of the millimeter, the gap of the round mouth is in the middle of 0.02mm to 0.05mm, to ensure the relative stable operation of the universal shaft in the whole process of cold rolling, and to increase the relative damage cycle time of the flat head and the flat head cover. To prevent the gap between the jaw plate and the roll flat head is too large, and the relative radial offset is expanded, especially at the moment of bite steel, the roll flat head and the flat head cover of the universal shaft will quickly offset to one side, resulting in the regular yaw of the universal shaft, the impact bearing capacity will be biased to one side, the total distance of the cross shaft will be more serious friction and hot, and the air intake system inside the rolling bearing will be destroyed.

Our technical engineers have basically improved the structure of the original cardan shaft. For the common existence of hard environment in the application of the cardan shaft of hot rolling mill, from the specific application of the extruder cardan shaft, the internal structure of the jaw plate and the rolling bearing of the cardan shaft flat sleeve have been upgraded. The flat head of the bushing is made into a removable liner plate type and the liner plate type is also dried for some unique round bushing, so that when the radial clearance is enlarged, it can be easily adjusted.

We have improved the hydraulic seal of the cross-shaft rolling bearing of the universal shaft of the extrusion machine. The double sealing property is used to strictly block the cooling water and dust of the extrusion machine from entering the inside of the rolling bearing, ensuring that the grease inside the rolling bearing is not easy to lose. In addition, the oil nozzle with a protective shell is dried at the top of the rolling bearing to easily fill the lubricating oil.