Nitrided high-speed steel roll suitable for bar cutting frame and manufacturing method thereof

Abstract

The invention relates to a nitrided high-speed steel roller used for a bar cutting rack and a manufacturing method of the nitrided high-speed steel roller, and belongs to the technical field of roller manufacturing. The nitrided high-speed steel roller comprises a roller neck and a roller body composed of a working layer, a transition layer and a core part. The working layer is composed of, by weight, 1.2-2.2% of carbon, 7.0-13.5% of chromium, 0.2-1.2% of nickel, 0.5-1.5% of molybdenum, 1.0-2.5% of vanadium, 1.0-2.5% of tungsten, 1.0-3.0% of niobium, 0.05-0.1% of rare earth, less than or equal to 0.04% of phosphorus, less than or equal to 0.04% of sulfur, less than or equal to 0.5% of manganese, 0.6-1.5% of silicon and the balance iron. The substrate strength of the working layer is greater than or equal to 600 MPa, and the tensile strength of the working layer is greater than or equal to 800 MPa. The substrate strength of the high-speed steel roller is improved, the grain is refined, the rolling environment requirement of the bar rolling mill cutting rack is met, and the rolling requirement of the cutting rack is met.

Description

technical field [0001] The invention relates to a nitriding high-speed steel roll suitable for a bar cutting frame and a manufacturing method thereof, belonging to the technical field of roll manufacturing. Background technique [0002] In the finishing rolling section of the bar mill, the split rolling technology is usually used. The split rolling technology is to use a billet to roll into two or more finished products of the same size by using the pass and guide. The technology was only applied to profile cutting at first, and the cutting and rolling technology has developed rapidly in some industrially developed countries since the 1970s. [0003] When split rolling is adopted, the traditional acicular bainite ductile iron material is still the majority at present, but the low single-groove rolling capacity of bainite ductile iron rolls and frequent roll changes have become bottlenecks for further increase in production capacity. The main performance In the following res...

AI Technical Summary

Problems solved by technology

[0004] (1) The life of the rolling groove is low, and the phenomenon of groove collapse occurs from time to time. The number of times of changing rolls and grooves is long and the time is long, which seriously affects the operation rate and output indicators. When the rolling volume reaches about 70t, rolling marks appear on the surface of the steel. To ensure For the size and surface quality of the product, it is necessary to replace the finished groove every about 2 hours, and it takes 10 minutes to replace a new groove. Only the slot change time per day has an impact on the operation rate of more than 9%

[0005] (2) The physical quality of the steel is unstable, and it is difficult to adjust the rolling groove in the later period of use. Due to the low hardness of the rolling groove, the cutting hole and the wedge tip of the pre-slitting hole wear very quickly, resulting in unstable material shape and uneven distribution, which is reflected in the finished product On the steel, there is a large change in the direction and size between each line and a single branch, and the impact on the finished product is more serious at the later stage of the rolling groove, so it is easy to produce unqualified products, and it is difficult to achieve stable negative deviation rolling

[0006] (3) After the roll is used, the reloading volume is large, and the roll consumption is high. Due to the different wear characteristics of each pass pass, in order to ensure the quality of the repaired roll, each time it needs to be reloaded by 6-10mm, and the roll consumption is relatively high.

[0007] (4) The labor intensity of the workers is high and the environment is poor. In order to ensure the quality of the finished products, the workers need to adjust the finishing rolling unit every 10 minutes, and because of the high temperature and high humidity around the rolling mill, it has caused great harm to the health of the workers

[0011] Due to the particularity of the material of ordinary high-speed steel rolls, the requirements for the rolling environment are relatively high, which cannot meet the current production needs and cannot meet the rolling requirements of the splitting stand in the finishing section of the bar mill. High-speed steel rolls have not been obtained. good effect

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