Process for manufacturing hot rolled steel strips by using compaction type continuous casting and rolling technique

Abstract

The invention discloses a compact continuous casting and tandem rolling method for producing hot rolling strip steel, including the following steps: 1) liquid molten steel passes through a long nozzle from a ladle to be cast to a pouring box, flows through a submerged nozzle from the pouring box to be cast in a crystallizer of a continuous caster and is continuously cooled in the continuous caster to form a casting blank; 2) a shearing machine is used for cutting a flat blank into certain size; 3) the flat blank enters a tunnel roller hearth heating furnace for heating; 4) the continuous caster is provided with a plurality of casting flows, one of which is in collineation with a rolling mill, the casting blank of other flows passes through a swinging section and is converged with the casting blank of the collinear flow and then is descaled by high pressure water; 5) the casting blank carries out rough rolling into an intermediate blank by a roughing mill group; 6) the intermediate blank is coiled and decoiled by a hot coiling box; 7) the head and the tail of the decoiled intermediate blank are cut and descaling by high pressure water is carried out to the decoiled intermediate blank; 8) the intermediate blank carries out finish rolling into a steel strip with standard thickness; 9) the steel strip is coiled into a finished steel coil by laminar flow cooling. The method is characterized by stable production technique, shorter production line, low equipment investment and high utilization rate of energy in the whole production process, etc.

Description

technical field [0001] The invention relates to a continuous casting and rolling process, in particular to a method for producing hot-rolled strip steel using a compact continuous casting and rolling process. Background technique [0002] The current thin slab continuous casting and rolling has a series of advantages such as short production process, low energy consumption, high labor productivity, simple equipment, low investment, and low cost. The price of hot-rolled coils produced is cheaper than that produced by conventional processes , showing great market competitiveness. [0003] Thin slab continuous casting and rolling lines that have been commercialized at present mainly include ISP (in-line strip production) process, CSP (compact strip production) process and FTSRQ (flexiblethin slab rolling for quality) process. [0004] In the ISP process, due to the close connection between the roughing mill and the continuous casting machine, there are the following problems: ...

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Problems solved by technology

[0004] In the ISP process, due to the close connection between the roughing mill and the continuous casting machine, there are the following problems: the first cutting machine is arranged after the roughing mill, and the continuous casting machine and the roughing mill are connected by continuous casting slabs, and the production The process is difficult to control; since the continuous casting machine is in continuous low-speed production, it is required that the originally high-speed roughing unit should also be continuously produced at low speed and synchronously with the continuous casting machine. It is easy to deform under the action of the casting slab; without heating, there is a huge temperature difference between the edge and the middle of the slab, resulting in surface defects such as cracks at the edge of the steel plate

Same as the CSP process, there is a long tunnel roller hearth heating furnace, and the length of the entire production line increases

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