Solidification quality control method for large-scale middle high alloy steel vertical-type continuous casting blanks

Abstract

The invention belongs to the technical field of continuous casting and particularly relates to a solidification quality control method for large-scale middle high alloy steel vertical-type continuouscasting blanks. By means of the method, the internal quality of the produced continuous casting blanks is obviously improved. The method includes the following steps that 1, during casting of the large-scale circular blanks, a tundish cart is driven to a casting position of a continuous casting machine, and an submerged nozzle is opposite to the center of a crystallizer and descends to an assignedposition; 2, a tundish rod insertion mechanism is opened to enable middle high alloy steel liquid to be injected into the water cooling crystallizer through the submerged nozzle; 3, a secondary cooling system, an electromagnetic stirring system and a roller clamping device are automatically started, and the circular blanks sequentially pass through the water cooling crystallizer, the secondary cooling system, the roller clamping device and an electromagnetic stirrer of a radiation area, then enter a heat preservation device of the radiation area and finally pass through an electromagnetic stirrer at the tail end; 4, after a supporting dummy ingot descends to an assigned position, casting is stopped, cutting by fire is conducted after the circular blanks are cooled to required temperature,and the cut circular blanks are discharged to a heat preservation indentation by a discharging roller to be cooled to the room temperature.

Description

technical field [0001] The invention belongs to the technical field of continuous casting, and in particular relates to a method for controlling the solidification quality of large-scale medium-high alloy steel vertical continuous casting slabs. Background technique [0002] Special steel is a key material required for major equipment manufacturing and national key project construction. It is a high-tech product among steel materials. Its production and application represent a country's industrialization development level and are the basic guarantee for national comprehensive competitiveness and national security. . [0003] At present, large-scale alloy steel continuous casting slabs are mostly produced by vertical bending or arc continuous casting machines. Limited by the metallurgical characteristics of continuous casting machines, this type of equipment is mainly used to produce low-alloy steel continuous casting slabs. For continuous casting slabs, it has high producti...

AI Technical Summary

Problems solved by technology

However, for large-scale continuous casting slabs, the cooling intensity in the secondary cooling zone is difficult to penetrate into the inner layer of the slab, which makes it difficult to control the solidification and feeding behavior of the slab, and the central feeding defect is prominent

In addition, the solidification rate of large-scale continuous casting slabs is low, and the solutes that are easy to segregate have sufficient time to diffuse and gather. The larger the section of the slab, the more prominent this problem

Therefore, central feeding defects and solute segregation become bottlenecks restricting the improvement of solidification quality of large-scale continuous casting slabs

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