Roll forming method of thick-walled ring forgings made of bearing steel

Abstract

The invention discloses a roll forming method for a thick-wall ring forging of bearing steel. The method comprises the steps that an intermediate billet is designed into a special-shaped ring billet first, wherein the position close to the inner wall is provided with a boss; various sizes of the special-shaped ring billet are calculated according to the isovolumetric principle; a special die is designed according to the shapes and sizes of the special-shaped ring billet; a bearing steel bar is heated to the deformation temperature, upset, punched, pre-rolled and manufactured into the special-shaped ring billet under the effect of the special die; the special-shaped ring billet is reheated to the deformation temperature and rolled into a thick-wall ring forging with the cooperation of suitable rolling parameters. By means of the roll forming method, the defects of grooves, folding and the like appearing in the rolling process of the thick-wall ring forging can be effectively overcome, and the rolling quality of the thick-wall ring forging is improved. The roll forming method is used for roll forming of the thick-wall ring forging.

Description

technical field [0001] The invention relates to a rolling forming method of a ring forging, in particular to a rolling forming method of a bearing steel thick-walled ring forging. Background technique [0002] The rolling forming of the ring refers to the plastic forming method in which the wall thickness is reduced and the inner and outer diameters are increased under the action of the rolling force of the main roll and the core roll. When this forming method produces thick-walled ring forgings, the flow velocity of the metal material near the inner and outer walls of the ring is higher than that of the metal material in the middle part, and the greater the wall thickness, the greater the difference between the two , if a rectangular ring blank is used for rolling forming, grooves will appear on the upper end surface of the formed thick-walled ring forging, that is, the height of the part near the outer wall and the part near the inner wall is greater than the height of the...

AI Technical Summary

Problems solved by technology

The first method will destroy the metal flow line on the end face of the forging, reduce the strength of the ring, and waste materials

Although the second method suppresses the height increase on both sides of the inner wall and the outer wall, it is easy to cause excessive metal materials to flow to the upper ends of the inner wall and the outer wall, where they accumulate and form folds; and if the pressing speed of the cone roller is too high Fast, it will also cause a serious temperature rise on the end face of the forging, which will seriously affect the quality of the forging

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