A Molding Technology of Large Hollow Grinding Ball

Abstract

The invention discloses a molding technology for a large hollow grinding ball and belongs to the field of metal wear-resistant materials. The technology comprises the steps as follows: a foamed plastic mold of the grinding ball is placed into a sand box; vibrating sand addition is performed on a vibrating unit; and the vibrating sand addition process is as follows: Stage 1: the vibrating frequency is adjusted, the sand box is vibrated at the low frequency, and dry quartz sand with the small granularity is added to the sand box while vibration is performed; Stage 2: the vibrating frequency is adjusted, the sand box is vibrated at the medium frequency, and dry quartz sand with the medium granularity is added to the sand box while vibration is performed; Stage 3: the vibrating frequency is adjusted, the sand box is vibrated at the high frequency, and dry quartz sand with the large granularity is added to the sand box while vibration is performed. The technology has the remarkable control effect on the surface defect of the grinding ball.

Description

technical field [0001] The invention relates to the field of metal wear-resistant materials, and more specifically relates to a molding process of large hollow grinding balls. Background technique [0002] The main grinding principle of the medium-speed mill is that the grinding balls roll between the upper and lower grinding rings to crush the minerals entering the grinding channel. The grinding balls and grinding rings are the main wearing parts, and they are usually placed for 5~ 10 grinding balls, with the enlargement of the equipment, the size of the grinding balls is also larger, the outer diameter is from Φ750mm to Φ1150mm, in order to reduce the weight of this large grinding ball, it is made of hollow balls, the wall thickness is from 135mm to 150mm, and the weight From 1.2 tons to 3.6 tons, and set 5 process holes, the hole diameter is Φ90mm to Φ100mm; because the hollow grinding ball bears a large impact load during operation, CrNiMo cast steel is used as the mater...

AI Technical Summary

Problems solved by technology

[0004] However, the technical problem in the above-mentioned application is that the large-scale hollow grinding ball manufactured by the above-mentioned preparation method is prone to product defects such as cracks and slag holes on the surface during the casting process due to the large size of the hollow grinding ball, and the size is relatively smaller. The larger the hollow grinding ball, the more obvious the product defects such as cracks and slag holes appear on the surface

[0005] Therefore, how to overcome product defects such as cracks and slag holes that are prone to appear on the surface of the existing large-scale hollow grinding balls during the casting process is a technical problem that needs to be solved urgently in the prior art

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