Method for continuous casting, continuoccs rolling intermediate and thin sheet blanket

Abstract

The production method of sheet billet conticasting tandem-rolling coil sheet is characterized by that said invention adopts the following technical measures: using conticasting machine and making pulling rate of casting blank low, and making the blank material have reasonable section; compactly arranging conticasting machine and heating furnace, making the conticasting blank output roller conveyer and inlet roller conveyer of heating furnace have double purpose, making inlet temp. of casting blank be above 900 deg.C; adopting double furnace and hating; and adopting small-cross charging and tapping process; two-high reversing rougher for three passes, four-high reversing rougher for one pass; and adopting thermal coiler box process of workpiece so as to raise coil sheet quality and reduce its production cost.

Description

technical field [0001] The invention relates to a production method of continuous casting and rolling coils of medium and thin slabs. In particular, it relates to the production process of medium-thin slab continuous casting and continuous rolling strip steel of carbon steel and low alloy steel, and belongs to the technical field of metallurgical metal pressure processing. Background technique [0002] At present, the traditional production process of continuous hot-rolled strip steel has the advantages of complete varieties, high output, flexible production, and large product compression ratio. Steelmaking by converter, continuous casting of 200mm-250mm thick slab, flame cutting, step-by-step Heating furnace heating, descaling, rolling by roughing mill, shearing, descaling, rolling by finishing mill, laminar cooling, coiling and coiling. The main disadvantages are: heavy weight of casting machine equipment, long rolling line, workshop The building is tall, occupies a large...

AI Technical Summary

Problems solved by technology

[0002] At present, the traditional production process of continuous hot-rolled strip steel has the advantages of complete varieties, high output, flexible production, and large product compression ratio. Steelmaking by converter, continuous casting of 200mm-250mm thick slab, flame cutting, step-by-step Heating furnace heating, descaling, rolling by roughing mill, shearing, descaling, rolling by finishing mill, laminar cooling, coiling and coiling. The main disadvantages are: heavy weight of casting machine equipment, long rolling line, workshop The building is tall, occupies a large area, and requires a large intermediate slab warehouse as a buffer between the continuous casting and rolling lines. The investment in equipment is large and the energy consumption is high. The hot charging rate of continuous casting slabs can only reach 60% to 65%. , the average furnace temperature is only 500-550°C; the slab is rolled for a long time in the rough rolling area, and the heat loss of the slab is high, so a higher slab discharge temperature is required; in order to compensate for the temperature difference between the head and the tail of the intermediate billet, the finishing rolling unit must Speed-up rolling is used, which will increase the capacity of the main motor for finishing rolling, and the shape of the product is difficult to control

[0003] Due to the thin thickness of CSP continuous casting slab, only 50mm~70mm, the casting speed is high, 3~6m / s, the rate of breakout in production is high, and the accident rate is as high as 50%; it is highly sensitive to peritectic steel and continuous casting cracks Many steel grades cannot be produced due to the limitation of steel. The billet length is generally 30m~50m, and a roller hearth heating furnace with a length of about 200m must be installed at the rear. Once the rolling mill fails, the continuous casting machine can only stop production, and the tunnel heating furnace occupies Large land area, complex equipment, difficult operation and maintenance, and high investment cost; in terms of process layout, there is little buffer space between the continuous casting machine and the heating furnace, and the loss of accident handling during continuous operation is large; this process layout does not have a roughing mill, One kind of slab thickness is rolled into finished products of different specifications through the finishing rolling mill, which requires high configuration of the finishing rolling mill