The kiln roller of rotary kiln is a solid steel drum, supported by bearings on the basis of the kiln. In order to save materials and reduce the mass, the wheel is equipped with holes in the plate, with the kiln roller center running through a shaft, two shaft necks installing between the two bearings. Wheel diameter is the 1/4 of wheel diameter, and the wheel width is generally 50-100mm higher than the tyre width.
Regarding to tyre and kiln roller material, currently there are two views. Someone keep the view that too large and heavy will not easy to change. In order to extend its service life, the material for tyre should be better than kiln roller and the hardness should be higher. Another think that roller speed should be 4 times faster than the tyre, thus the surface abrasion will be faster. It will affect the lifetime of the tyre, thus the material of kiln roller should be better than tire.
Henan Zhengzhou Mining Machinery currently use the ZG45 manufacturing tyres with the surface hardness not less than 170HB, ZG55 manufacturing roller with the surface hardness less than 210HB, and the supporting wheel hardness is 30-40HB higher than the tyre hardness. When operating, the supporting roller bearing is with great work load, high temperature, the surrounding dust. In order to avoid the heat radiation effect of the kiln body, it’s generally equipped with easily disassemble antipyretic asbestos board on the kiln rollers of the end of the kiln body.
At present, the bearing of large rotary kiln has a sliding bearing, and rolling bearing. ZK adopt the most advanced rolling bearings in the bearing set, which has the following advantages:
1. Running fast, small friction resistance.
The friction factor of the rolling bearing is much smaller than that of the interactive bearing, so the operation is light and the friction resistance is small. Power saving is inevitable. Due to rolling friction, the starting torque of the kiln is reduced relatively.
2. Smooth operation, less maintenance workload.
The manufacturing precision of rolling bearing is high. the operation of the kiln is more stable than that of sliding bearing. Meanwhile, maintenance work is very few, the fault is less than the sliding bearing due to considering the lifetime factor adequately.
3. Good heat resistance
As long as the appropriate grease, bearing roller bearings can be safely operated at 120℃, improved a lot compared with the 65℃of sliding bearing.
