Determination of dynamic component reactions in support bearings of rotor saws for cutting hot rolled (message 2)

Abstract

For modern rolling production, the issue of strength and reliability of rotary saw designs, which are designed for cutting hot rolled products, is relevant. One of the factors that reduces the reliability of a rotary saw is the insufficient durability of the bearings of the shaft of the high-speed disk, which perceives the cutting forces. Practice shows that the applied methods of calculating the strength of support bearings do not allow taking into account all possible factors that affect the reliability of bearings in the cutting process. First, as it turned out, during operation, the saw blade has a radial beat, possibly due to an error when cutting the teeth of the blade and the eccentric landing of the blade on the seat when replacing it. Also, due to the fact that the process of cutting with a rotary saw is very short-term, the cutting force is considered to be the impact force. The purpose of this work is to determine the durability of the bearings of the disc shaft of a rotary saw, considering such factors as the radial beating of the disc and the shock load during the cutting process. As you know, during long-term operation of the object, the place for landing the cutting disc on the faceplate wears out, sometimes there is an error in the hole when making a new disc. Therefore, there is an eccentricity of the center of gravity of the disc. The presence of this eccentricity is considered in the work when determining the required forces using D'Alembert's principle of conditional balancing of forces. Given that the duration of cutting is a short-term process (lasts 0.105 sec.), when determining the reactions in the supports of the disk shaft that occur under the action of cutting forces, it is possible to consider the cutting process as an impact phenomenon. Due to the fact that the process of cutting with a circular saw is very short-term, the cutting force is considered the impact force. The magnitudes of the reaction forces in the bearings are determined during cutting using the theorems of impact dynamics: the theorem of impulses and the change of kinetic moment. For the possibility of theoretical determination of the effect of disk beating on the reaction in the bearings of the bearing shaft, experimental studies of disk beating and determined cutting forces were carried out