MOVEMENT SPECIFICS OF A GERM WITH COMPLEX SHAPE ON THE PELLETIZING DISK IN IRON-ORE PELLETS PRODUCTION

The movement specifics of a germ with complex shape on the pelletizing disk in production of iron-ore pellets are considered. As a result of the analysis of the forces acting on the cubic germ during its roll on the charge scull (CS) in the conditions of plastic deformation, a mathematical model was build that allows the optimal parameters of the pelletizer to be determined for the production of pellets based on the technology of a forced germ formation. Two particular cases of germ stability on the pelletizer CS and the conditions for the over-coming of the stability associated with the formation of a roll are considered. The germ stability, or conversely, its roll is determined by the horizontal position of its mass center relative to the support edge located across the probable direction of the roll. If the line of the acting force (gravity force) moves behind the support edge and the reference plane, a force moment will be generated which will lead the germ out of the stability state and form a germ roll. The first special case of germ stability on the inclined plane is the absence of a roll on the CS with a minimum value of the centrifugal force corresponding to the location of the germ in the central areas of the pelletizing zone or to operation of a working element with a low rotation speed (n  <  3  rpm) . A more general case of the transition of the germ from the state of stability into the roll regime on the inclined plane of CS is the work of the pelletizer when centrifugal force is relatively high (n  >  3  rpm) and location of the germ in peripheral areas of the working zone of the pelletizer. For these cases the conditions for germs roll on the CS in the pelletizer working zone and correcting measures in the conditions of plastic deformation during the corners and edges crushing are formulated. The features of the germ movement in the working zone of the pelletizing disk are shown. The conditions for correcting the regime of forced germ formation are provided, and the measures are indicated for the purposeful impact on the crushing factor of a germ. It was established that for the organization of the regime of a germ roll with complex shape the angle of disk inclination to the horizon should be set depending on the frequency of its rotation and the crushing factor of germs.

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