Many manufacturers and insipsers have recently reacted such a problem. After they have used time, the ball mill has problems, mostly because the machine is old, the mill is loose. They want to ask before this failure What preventive measures have mainly reflected in the main failure form of
, the force, the mutual extrusion, grinding between the mill The main mechanism of ball wear is:
(1) Cutting and chiseling wear. The surface of the grinding ball can be broken down into a normal force and tangent force, and the sharp material (abrasive particles) relative to the mill, in the method of embedding the surface under the action of the normal force, and the tangential force pushes the surface of the grinding. . Low hardness abrasive grains produce shallow scratches on the surface of the grinding ball, and the high hardness abrasive particles cause the cutting groove. Metals in the scratches and cutting grooves are plastic deformation stacked on both sides and the front section. The high strain rate causes the metal internal position of the metal that has occurred, forming a cytoplad structure, and the properties become hard, and then repeatedly rolled, generate strain fatigue cracks, and the properties are hard to change, and then repeatedly rolled, produce it. Strain fatigue cracks, expand to the surface, resulting in fritting. When the grinding of the grinding ball is large, the chiseling effect occurs, forming a chisel pit, the metal is directly premature or plasticity, and ultimately forms iron filings due to the fatigue;
(2) Fatigue wear. The milling ball is repeatedly impacted, and the pressure and sliding of each other are repeatedly impact, mutually squeezing and sliding, and under the pressure of the alternation, it causes an alternating Hz contact stress. In the sub-surface layer of the material produces the maximum alternating cut stress, the edge of the contact area produces peak tensile stress, resulting in a brittle phase of the subset layer, fatigue, crack, crack expansion, and interleaving, ultimately to peel off the grinding ball epidermis . If the crack is generated in a deepest portion, the brittle phase and the defect are extended to the interior to form a larger depth crack. Cracks will be incorporated with the surface, and the surface of the grinding ball is pulled off. Fatigue wear of the grinding surface;
(3) brittle wear. In the wet
ball mill used in the mine, the wear medium (which belongs to the electrolyte solution) and the wear working condition acts on the surface of the material, and corrosion wear occurs. The consumption of the wet mill grinding body reaches 5 to 7 times the dry type. The loss rate of materials under the corrosion wear mechanism is much higher than that of corrosion and wear, alone due to the loss rate of their material. Corrosion damage the mechanical properties of the surface of the material, so that the material is accelerated, and the wear continuously generates \"new\" material surface, and the rate of corrosion is improved.
