Out-of-roundness control method for short-stress-path rolling mill

Abstract

The invention discloses an out-of-roundness control method for a short-stress-path rolling mill. The out-of-roundness control method comprises the following step (1) of designing the size, close to the size of a finished product, of a K3 rolled piece in a rolling procedure; the step (2) of designing a true circle K2 pass, and using a finished circle-circle pass for circle gauging; adopting a circle gauging process of ellipse-circle-circle-circle true circle pass for four passes K4, K3, K2 and K1; the step (3) of modifying a K1 final pass for ensuring that the size of two shoulders of the passis larger 0.5 mm than the size of the groove bottom of the pass; the step (4) of modifying K1 guide wheels, and ensuring that a standard K2 material pattern is consistent with the R arc of the K1 guide wheels, and the material pattern is completely fit with the guide wheel for improving the support effect when the material pattern is clamped by the guide wheels; the step (5) of using double rows of guides for K1 inlet guides, and modifying the guide wheels in the back row; increasing the diameter of the guide wheels in the back row, so that the clearance between the guide wheels in the back row is consistent with the clearance between the guide wheels in the front row when the material pattern is clamped by guide rollers in the front row, and a K2 rolled piece is supported through the double rows of guides; and the material pattern has the support effect of eliminating the axis error of a finished product.

Description

technical field [0001] The invention relates to a method for controlling the out-of-roundness dimensional accuracy of a short stress line rolling mill. Background technique [0002] Spring round steel is special railway equipment for high-speed rail, and the profit per ton of steel has been maintained at 1,000 yuan / t for a long time. However, spring round steel has extremely strict requirements on dimensional accuracy: the out-of-roundness must be controlled within 0.2, otherwise it will seriously affect the fatigue life of 5 million times of high-speed rail spring fasteners. [0003] At present, most of the rolling mills of domestic excellent special steel mills are short stress line rolling mills, which cannot meet the dimensional accuracy requirement of 0.2 out-of-roundness with the traditional production process. Three-roll mill. The rolling mill consists of three rolls distributed at 120° to form a triangular pass. The rolled piece bears three-dimensional compressive ...

AI Technical Summary

Problems solved by technology

However, the method of controlling the dimensional accuracy of the rolling mill has the following problems: 1. The investment of the rolling mill is relatively large. The price of a KOCKS rolling mill imported from Germany is about 56 million RMB, and that of domestic Xizhong is also about 25 million RMB. Manufacturers of special steel long products are discouraged; 2. It is difficult to adjust, and the finished product is prone to three-sided folding and edges and corners

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