A Multi-pass Curvature Decreasing Straightening Process

Abstract

The invention discloses a multi-pass curvature-decreasing straightening process. The straightening process uses a model to calculate the maximum meshing amount required for straightening the steel plate to be straightened according to the information of the steel plate to be straightened, and combines the straightening with the straightening machine The straightening capacity determines the straightening pass, allocates the setting amount of the entrance roll gap and the exit roll gap of each pass, and calculates the setting amount of the exit side roll by using the elastic recovery deformation model, so as to avoid warping at the head and tail of the steel plate and ensure the smooth connection of each pass. , so that the steel plate can achieve multi-pass curvature decreasing straightening. Using this straightening process can broaden the straightening range of the original design of the straightening machine, and at the same time reduce the uniformity of stress distribution along the thickness direction of the steel plate after straightening, and improve the shape quality of the steel plate.

Description

technical field [0001] The invention relates to a cold straightening process, in particular to a cold straightening process which adopts a multi-pass curvature decreasing method to improve the straightening ability and straightening quality of a straightening machine, and belongs to the technical field of steel rolling. Background technique [0002] Various shape defects often occur in the rolling process or in the subsequent cooling and transportation process, such as bending of bars, profiles and pipes, bending, waves, and buckling of plates and strips. Therefore, it is necessary to eliminate defects such as bending under the action of external force through various straightening processes, so that the product can reach a qualified state. [0003] The straightening machine is the equipment for straightening metal profiles, bars, pipes, wires, etc. The straightening machine squeezes the bars through straightening rollers to change the straightness. The more the number of s...

AI Technical Summary

Problems solved by technology

However, the increase in the number of straightening rollers increases the manufacturing cost of the straightening machine. In order to save the manufacturing cost, the straightening machine manufacturer will try its best to choose the design scheme of the least straightening rollers on the premise of meeting the needs of users.

However, with the continuous upgrading of rolling products in steel mills, the range of strength and thickness of steel plates continues to expand, and the straightening range of the original straightening machine gradually cannot meet the needs of new products, and the flatness of steel plates after straightening cannot meet the needs of users. need

In order to straighten the steel plate beyond the original design capacity of the straightening machine to the greatest extent, most users of the straightening machine adopt the method of increasing the reduction amount of the straightening roller at the entrance side to increase the plastic deformation of the steel plate and improve the straightness of the steel plate after straightening. However, there are two problems in this method: firstly, when the roll gap on the exit side is set to the thickness of the plate to be straightened, it is limited by the maximum inclination of the straightening machine, and the straightening machine will not be able to continue down after the entrance reduction reaches a certain limit. Therefore, the straightening quality of the steel plate cannot be fundamentally improved only by increasing the reduction amount of the straightening machine on the entrance side; secondly, when the straightening machine straightens the steel plate under the state of excessive inclination, its straightening The internal stress gradient of the steel plate along the plate thickness direction is too large, resulting in poor uniformity of internal stress distribution, and the steel plate may be warped again during the cutting process, which will affect the user’s use

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