Cement, Energy and Environment

Figure 5. Impact plate with typical wear pattern (top) and partial new hardfacing (bottom). tunnel construction. The spiral's crown, which is subject to extreme wear, is assembled with segments made of bi-metal cast iron. These bi-metal cast iron parts consist of 50% wear resistant chilled casting materials and 50% cast iron steel. The segments can then be welded together and attached to the screw by 3 - 5 times in comparison to a conventional steel solution. If required, these bi-metal cast components can be regenerated, which costs substantially less than purchasing a new screw conveyor. Screw conveyors a: e also used to transport bulk goods when unloading ships. These conveyors are manufactured using a combination of steel sections, cast iron steel, and chilled cast components. The screw flights made of chilled chrome casting are screwed onto the base structure for this application. This simplifies connecting the wear resistant screw flights and also offers an easy-to-maintain solution if one of the wings must be replaced due to intense wear. Hardfacing of grinding rollers and grinding discs Over the past few years, a transition could be observed in - fine grinding plant technology. For decades, ball rPills were used exclusively in cement plants. These mills are gradually being replaced and vertical roller mills and high– pressure rolls are primarily used today. These are applied in the cement industry as well as for raw meal processing, the grinding of blastfurnace slag, and for brick grinding. The components subject to wear, such as the grinding rolls and the grinding discs, have been 16