New development of forging grinding ball production technology

Industrialization and the improvement of human quality of life have led to the development of the entire mining industry. Grinding balls have become a necessary product for crushing and grinding in mines. At the same time, as a consumable in the industry, the cost of grinding balls has caused headaches for many mining companies. Under the same conditions as miners, forged grinding balls have certain cost advantages over chromium cast balls, so the continuous development of forged steel balls is inevitable. So far, the production process of forged steel balls has gone through three stages: the traditional process, the cross-hot rolling and the rotary cutting process.

Grinding balls

As the name suggests, traditional forged balls are forged steel balls. Air hammers are used to forge raw materials to a certain extent, improve compression ratio, make the structure of wear-resistant balls denser, and improve toughness and hardness. In traditional processes, the material is first cut to size, then heated to a certain temperature with coal or natural gas, and then gas hammer forging, heat treatment and product inspection.

Traditional technology has many disadvantages, mainly due to low production efficiency and artificial control of product quality, which can easily cause serious environmental pollution, insufficient physical strength of workers, thermal radiation and noise radiation, which are harmful to the human body. Workers' health. The quality of steel balls is greatly affected by workers' labor ability, and the quality of steel balls is uneven and cannot be guaranteed.

With the development of the times, traditional technology has gradually faded out of the historical stage and has been replaced by oblique rolling technology. The basic idea of ​​the oblique rolling process is to heat the entire round steel with an electric furnace, transport it to the roller through a conveyor belt, and drive the roller to rotate through an electric motor and reducer. The rollers can be made into balls using their own ball groove design.

This process does not require blanking and gas hammer forging, which greatly improves production efficiency, greatly reduces workers' labor intensity, and greatly reduces noise and other hazards. Inclined treading technology is a leapfrog development in the forging steel ball industry. However, there are many defects in the process, such as surface mass and roundness. The surface defects of steel balls produced by inclined pinning technology are skin inclusions, lack of flesh, excessive combustion, protrusion and high non-roundness. Moreover, when the diameter of the steel ball is greater than 50mm, all indicators of the steel ball cannot meet the requirements of the relevant standards. Steel balls with diameters greater than 90mm cannot be produced by cable-stayed technology.

With the development of mining machinery, the diameter of the ball mill is getting bigger and bigger. At the same time, with the emergence of semi-self-grinding machines, the demand for ball mill balls in mines has gradually increased from small diameters. Obviously, traditional technology and tilt tie technology cannot meet the needs of the mine. Some machinery companies have developed automatic rotary cutting and rolling forging production lines that can produce steel balls with diameters of 20-150 mm. Due to the greatly reduced manual intervention and process switching, the product quality between different batches has high stability.

During the heat treatment process, an ultra-advanced tempering process is adopted, and an advanced heat treatment process is developed in combination with experts from scientific research institutions. Through multiple quenching temperature control and continuous tempering, the body hardness uniformity and overall wear resistance of the grinding balls are better.