Method for processing profiled bar with asymmetrical cross section

Abstract

The invention discloses a method for processing a profiled bar with an asymmetrical cross section. The method is characterized in that a to-be-rolled profiled bar with the asymmetrical cross section is subjected to mirror pairing and combining in the direction of a vertical axis (Y axis), converting the asymmetrical cross section into a symmetrical cross section, improving the rolling condition, then rolling the bar with a symmetrical cross section by a four-roll universal mill, and finally dissecting the rolled semi-finished product with the symmetrical cross section by a metal dissecting device, so as to obtain two qualified finished bars which have the asymmetrical cross sections and are the same in size and shape. The method has the advantages that the rolling condition of the profiled bar with the asymmetrical cross section is improved, so the rolling by the four-roll universal mill is realized; and the rolling speed is high, the rolling efficiency is high, and the production capability is greatly improved.

Description

technical field [0001] The present invention improves the rolling conditions of the asymmetric complex-section profiled material and adopts a four-roller universal rolling mill for rolling processing. The method can realize efficient, economical and high-quality processing of such difficult-to-roll hot-rolled profiled material. Background technique [0002] Hot-rolled section steel is a solid strip of steel with a specific cross-section shape, which can be divided into simple section, special-shaped section and other categories. Except for a small number of section steel products such as square, round, and flat, which belong to simple sections, most section steel products are special-shaped sections. Because of the obvious convex and concave branch parts of the cross-section, the special-shaped bar (special-shaped cross-section steel) has a complicated cross-sectional shape and is difficult to roll and form. Whether the product appearance is symmetrical or not is one of the...

AI Technical Summary

Problems solved by technology

[0004] 1. There are obvious roll diameter differences in each part of the pass pattern. The metal in each part of the rolled piece contacts the roll and participates in the deformation time in sequence. There is mutual transfer of metal between parts of the section, and the temperature, deformation and relative speed of different parts are different. , there is serious non-uniform deformation, each part of the cross-section is restrained by each other during the deformation process, and the temperature distribution of the cross-section is not uniform

[0005] 2. The passes of the asymmetric cross-section steel need to be inclined, which makes it difficult to bite in; during rolling, there is a large axial force on the roll, which makes the rolling unstable, difficult to operate and control, and prone to serious bending and torsion of the rolled piece

[0006] 3. The rolling of the head and tail of the rolled piece is more unstable, and the size fluctuation is larger than that of the middle part;

[0007] 4. Uneven cooling and shrinkage after rolling, thermal stress causes the shape to be easily bent or twisted, and the size will also shrink, and there is a large internal residual stress in the finished product;

[0008] 5. There is a relative additional flow of metal inside the pass, which increases the energy consumption of rolling, accelerates the wear of the pass, consumes a lot of spare parts such as rolls and guides, and makes quality control difficult, which affects the quality of the rolled material and the rolling capacity is relatively high. lower;

[0009] 6. The adjustment of the rolling mill, the design and installation of the guide device are also relatively complicated;

[0010] 7. The law of metal deformation is extremely complex, and it is difficult to accurately calculate the width of the hole pattern. Many aspects of process design still need to be dealt with by experience, and personal practice is very important.

However, L-shaped steel (angle steel with unequal sides and different thickness), bulbous flat steel and other complex section steels with asymmetric horizontal axis (X axis) and vertical axis (Y axis) are difficult to be rolled by universal method. It is rolled by the traditional two-roll method, but it is difficult to overcome various production inconveniences caused by the two-roll method.

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