Finite Element Analysis And Research Of Grinding Procedure Of Back-up Roll In Hot Rolling 1880

Regular back-up roll grinding is performed in practice to remove surface and sub-surface initiated cracks. If removal amount is not sufficient enough during the grinding operation, cracks could propagate and even the flaking and spalling may occur later, causing significant economy losses. However, the effective service life of back-up roll will be reduced if removal amount is excessive, which is also wasteful in economy. The objective of this dissertation is to research and optimize grinding procedure to assure sufficient and logical stock removal.Based on the methods and procedures of establishment and analysis of ABAQUS finite element model, model data processing by using Matlab, studying on the contact stress distribution and normalization rules in back-up roll and between rolls, establishing grinding idea by taking cumulative fatigue damage value as parameter of back-up roll’s damage, and accurate simulation of roll grinding procedure by using Matlab, the whole idea of back-up roll’s grinding system on condition of load spectrum example is built. In order to test and verify the grinding system, the actual statistical load spectrums of frame F1-F4 is applied to replace the load spectrum example. At last, the new back-up roll’s grinding system is feasible enough in the actual case(random in roll’s changing tonnage and frame).The main research contents and results can be summarized in the following points:①Establish and analyse ABAQUS finite element model. On condition that the results of model are correct, the factors of rolls’ curve, chamfering, PC crossing angle, temperature field, rolling torque and so on must be considered when building ABAQUS models.②Process ABAQUS model’s stress data by using Matlab. Determine the leading contact stress which leads to fatigue damage of back-up roll by comparing with the stress results of Hertz theory, at the same time, circumferential, radial and axial distribution of the leading contact stress in back-up roll are required.③Based on normalization rules of contact stress distribution in back-up roll on different loading conditions, contact stress distribution of all positions in loading spectrum example table can be ascertained. The distribution of fatigue damage and cumulative fatigue damage can be obtained simultaneously by transformed via S-N curve.④Simulate roll grinding procedure by using Matlab accurately. After steady grinding system in ideal case(fixed in roll’s changing tonnage and frame) is established, the new grinding system of back-up roll in practical situations(random in roll’s changing tonnage and frame) can also be established by researching the relationship between roll’s changing tonnage and back-up roll’s grinding amount on frame F1-F4.⑤The new grinding system of back-up roll is tested and verified by the actual statistical load spectrums of frame F1-F4 replacing the load spectrum example.