Round steel rod continuous rolling method with diameter less than Phi 100 mm, and hole type system

Abstract

The present invention relates to a light-size round steel continuous-rolling method. It adopts a box-square-oval-round-oval-round system and makes the blank undergo the process of continuous rolling treatment by means of alternative six stands of vertical mills and horizontal mills so as to obtain the finished product, and before intermediate round pass stand and round former stand an inlet guide wheel is set.

Description

technical field [0001] The invention relates to a round steel continuous rolling method, in particular to a round steel continuous rolling method with a diameter less than φ100mm. Background technique [0002] At present, the conventional small round steel and wire bar steel mills at home and abroad are multi-stand rolling mills (the number of stands is generally greater than 12), which is similar to the continuous rolling mill of 6V-H (large stand spacing, large roll diameter, and long roll body length). The rolling mill generally rolls larger-sized round steel (see "Metal Plastic Processing", Wang Tingpu, Metallurgical Industry Press, 1988), and adopts a single guide wheel D 0 The box-square-ellipse-round hole system is shown in Figure 1. The 6V-H continuous rolling mill is arranged alternately between vertical and horizontal, the torsion tendency of the rolled piece is small, and the speed of each stand can be adjusted independently, and the extension can be distributed ...

AI Technical Summary

Problems solved by technology

However, there are limitations in the specification range of round steel products. According to the original design regulations, the minimum diameter specification of round steel that can be rolled by 6V-H continuous rolling equipment is φ100mm. In the past, due to the limitation of technological conditions and other factors, the actual round steel that could be rolled The lower limit of diameter size is φ110mm, and the specification of φ90mm has exceeded the lower limit of the original design specification of the six-rolling continuous rolling mill. According to the conventional design, the smooth rolling of φ90mm round steel cannot be guaranteed, and all six-stand passes must be redesigned.

During the continuous rolling of conventional small round steel and wire rods, the distance between the rolling mills is generally 2-3 meters, while the 6V-H continuous rolling mill for preliminary rolling was originally designed to roll larger-sized continuous rolling billets, and the distance between the stands is relatively large (5.5 meters), and the original design of the rolling mill adopts a single guide wheel system for round billet rolling. The biggest difficulties for small-size rolling are: large stand spacing, large torsional moment on the rolled piece, small clamping force, poor stability, and poor rolling stability. Pieces are prone to fall and twist in the rolling mill, resulting in defects such as ears and folds on the surface of the round steel. In severe cases, it may cause serious accidents

[0003] Generally, the roll diameter of small round steel mills at home and abroad is 500-650mm, and the length of the roll body is relatively short (about 800mm), while the length of the roll body of the 6V-H continuous rolling mill for preliminary rolling is 1100-1300mm, the roll diameter is 700-800mm, and the rolling torque is large. The roll bounces a lot during rolling, especially according to the original design that there is no rolling guide wheel at the entrance of the H4 pass, which makes the operation and adjustment more difficult, and is not conducive to stable rolling. This constitutes a contradiction with the high precision required for small-sized round steel. Higher requirements are put forward for the pass design, and the pass design must take into account the three factors of rolling stability, dimensional accuracy, and operation adjustment

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