Large-size rectangular steel production process combining billeting, continuous rolling and controlled cooling

Abstract

The invention discloses a large-size rectangular steel production process with cogging, continuous rolling and cooling control combined. The large-size rectangular steel production process comprises the following steps that a round steel blank is fed into a heating furnace to be heated through a conveying roller way, and steel tapping is carried out when the temperature of the round steel blank ranges from 1,050 DEG C to 1,150 DEG C; a high-pressure descaling machine is used for removing scaly oxidization scrap iron on the surface of the round steel blank; the round steel blank is burst into a flat steel blank with the rectangular section through a cogging mill; finished rectangular steel is obtained through rolling of a continuous rolling machine; the rectangular steel is conveyed to a hot saw area to be sawn; and the rectangular steel obtained after sawing is finished is conveyed to a stepping cooling bed, the rectangular steel cooled and conveyed to an outlet through the cooling bed is subjected to slow cooling, and the in-pit temperature of the rectangular steel is controlled to range from 380 DEG C to 420 DEG C. By means of the method of the process, the production process is low in cost and high in efficiency, a high-cost steel ingot forging process is replaced, and therefore the size range of the rectangular steel produced in a continuous rolling manner is widened, the production manner of the large-size rectangular steel is enriched, and the new production process of the large-size rectangular steel is created.

Description

technical field [0001] The invention relates to the field of rolling production of flat steel, in particular to a large-size rectangular steel production process combining blanking, continuous rolling and controlled cooling. Background technique [0002] Rectangular steel for forks, rectangular steel for molds, rectangular steel for railway forks and other rectangular steels have high requirements on the mechanical properties of materials and high requirements on external dimensions. Currently, continuous casting slabs or steel ingots are used for rolling Or used after forging; the above-mentioned rectangular steel with a thickness of less than 50 mm and a width of less than 150 mm is produced by using small and medium-sized square billets or rectangular billets with multi-pass continuous rolling process to ensure its mechanical properties and external dimensions; thickness greater than 50 mm and width greater than The 150mm above rectangular steel is forged by continuous ca...

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Problems solved by technology

[0005] The purpose of the present invention is to overcome the deficiencies of the prior art and provide a large-scale rectangular steel production process combining billet opening, continuous rolling and controlled cooling. The production process is low in cost and high in efficiency, replacing the high-cost steel ingot forging process , thereby expanding the specification range of rectangular steel produced by continuous rolling, enriching the production method of large-size rectangular steel, and creating a new production process for large-size rectangular steel; through the large-reduction blanking process, the core is fully deformed , to ensure that the material is more dense, and on the basis of greatly improving the specifications of the rectangular steel produced by the continuous rolling process, the mechanical properties are guaranteed; through the function of the continuous rolling mill, the shape and size of the rectangular steel can be controlled with high precision and strong controllability, and can be produced according to user needs. Rectangular steel with rounded corners and right angles in cross-section; through the self-straightening function of the cooling bed and the design of controlled cooling, it can solve the problems that rectangular steel is prone to bending and twisting; the combination of fixed hot saw and mobile hot saw can ensure that users Different cut-to-length and tolerance requirements; the rectangular steel with a thickness less than or equal to 90mm is tightly packed and then hoisted into the pit for slow cooling by driving, which can make the slow cooling effect of the rectangular steel better; During the steel process, the rectangular steel is pushed to the traversing entrance roller table through a group of steel pushing devices, which solves the problem that the rectangular steel cannot be moved to the traversing entrance roller table by its own weight; the cooling bed is equipped with an insulation cover to avoid the surrounding area of ​​the cooling bed. The large air convection ensures uniform temperature around the cooling bed, and eliminates the problem of side bending and torsion of rectangular steel due to uneven cooling around the cooling bed

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