Material of coal mill liner

- Sep 14, 2019-

Multi-component low alloy steel

Currently used is 40CrMnMoSiRe alloy material. After oil quenching, the material has both hardness and toughness. The hardness can reach above HRC45, and the impact toughness can reach 10J/cm2 (U-shaped notch value). The advantage of this material is that the price is not high, and the performance is comprehensive and stable. It can be cut and welded, and it is easy to install and use, and has been widely used. However, the wear resistance is general.

2. Medium chrome steel

The medium-chromium steel material is also widely used in the lining. The material has two treatment methods, one is oil quenching, the hardness reaches HRC45 or above, the impact toughness can reach 10J/cm2 (U-shaped notch value), and the other is air-cooling. Or air-cooled, hardness can reach more than 45, but need higher carbon content, and air cooling or air cooling process is generally uneven, the internal and external hardness has a certain difference, the stress is also large, so there is no oil quenching process, medium Due to the high chromium content of chrome steel, it also adds molybdenum, nickel and other elements. The wear resistance is higher than that of low alloy materials, and the wear resistance is better and the service life is longer. However, the welding performance is slightly lower than that of low alloy steel.

3. High chromium cast iron series

There are three kinds of high-chromium lining materials: KMTBCr15Mo, KMTBCr20, and KMTBCr26. High-chromium alloy has high wear resistance due to the high wear-resistant carbide of M7C3 type in the structure, of course, the cost is also high, high chromium cast iron The material can be welded with poor cutting performance and high brittleness. It is generally used on large mills and double-inlet and double-out mills that require high wear resistance.

4. High manganese steel

Menggang series materials include Mn7 (medium manganese steel), Mn13 (high manganese steel), Mn13Cr (alloy high manganese steel), Mn26 (ultra high manganese steel) Mn26Cr (alloy super high manganese steel), etc. Other alloys are used to improve the wear resistance. Because high manganese steel has impact hardening properties, it is generally used in large impact conditions. In the small multi-energy impact condition of the coal mill, most manufacturers have already eliminated it.

5. Other materials

In addition, there are other alloy materials, such as 30CrMnMoSi, 40Cr2MoRe, etc., which are close to the low alloy material above, and generally have less application.