Finite Element Analysis Of Strength Influence Of The Spindle Balance Mode Of Heavy Plate Mill On Spindle

Heavy plate mill is a significant equipment in steel rolling production. Universal spindle and universal coupling are core components of main transmission system. The cross shaft universal spindle is widely used due to its characteristics of big driving torque, big placed dip and stable transmission. Balancing device is often used to counteract gravity due to the large mass of the spindle and coupling. To ensure the stabilization of universal spindle, overbalance is generally used and balance coefficient is from1.1to1.6.This article takes universal spindle and coupling as the research objects, using finite element software ANSYS Workbench to analyze their static strength and trying changing the balance mode (a balance force is split into two) to improve the force situation of them. The fork structure optimization has improved its stress concentration. The main contents and conclusions of the article include the following points.1．Mechanics analysis of universal spindle draws the conclusion that shear and moment in the middle part of the spindle are maximum. The static strength analysis of the spindle shows that equivalent stress value on the shoulder fillet in the middle part of the spindle is largest, and there is stress concentration in this position. Bending moment on the spindle sharply decreases after changing balance mode. But the maximum equivalent stress value after changing balance mode on the spindle decreases less than before. It is concluded that changing balance mode improves the force situation of the spindle to a certain extent.2．Torque makes the spindle generate torsional deformation and balance force makes it generate deflection deformation. Changing balance mode can substantially decrease the deflection of universal spindle, but almost has no effect on spindle’s torsional deformation.3．The strength analysis of the universal coupling has showed no matter whether to change balance mode, the maximum equivalent stress of the fork is much larger than cross shaft’s. So the fork is easier to be destroyed than the cross shaft. After changing balance mode, the maximum equivalent stress value of the fork doesn’t decrease, but the cross shaft’s reduces by5.9%. So, changing balance mode can reduce the tension of the coupling and the impact to the cross shaft, improving the mechanical situation of universal coupling.Universal spindle will be out of shape under the role of balance force and torque. The larger the balance force is, the larger their deformation will be. So, small balance coefficient is advised. Deflection deformation of the spindle generates large tension on universal coupling. In addition of the role of large torque, the coupling comes about stress concentration because its structure is complex, and it is easy to have failure including deformation and fracture. Changing balance mode can decrease the maximum bending moment of the spindle, reducing the maximum equivalent stress of the spindle and the coupling, improving the force situation of them. Relatively speaking, the spindle and the coupling strength is improved. Structure improvement of the fork has improved the stress concentration and increased the structure strength of the fork.