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Ball mill steel balls are divided into forged and rolled steel balls and cast steel balls in terms o

Time:2018-09-12 Click:74

    Ball mill steel balls are divided into forged and rolled steel balls and cast steel balls in terms of production technology. In recent years, the price of forged and rolled steel balls has been very unstable due to the great fluctuation of the price of finished round steel. Especially since 2016, in order to control the environment, the state has also given us a blue sky. Major steel mills have begun to limit or stop production and rectify, which has led to the rapid growth of steel prices, reaching a record high. By comparison, the market of forged and rolled balls is becoming smaller and smaller.
    Cast steel balls are divided into high, medium and low chromium steel balls, which have low cost and strong abrasiveness. The domestic market share is over 80%. Especially medium chromium steel balls, which have high performance-price ratio, are the mainstay of the steel ball industry.
    Brief Introduction of Medium Chromium Steel Balls:
The chromium content ranges from 3.0% to 7.0% and the carbon content ranges from 1.80% to 3.20% are called medium chromium spheres. The impact value AK is more than 2.0J/2. The national standard requires that the hardness of medium chromium spheres (HRC) must be more than 47. In order to ensure the quality of steel spheres, high temperature tempering treatment (in order to eliminate casting stress) should be adopted. If the surface of steel spheres is dark red, the product has been tempered at high temperature, such as the surface of steel spheres. The metal color still shows that the product has not been tempered at high temperature.

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