There are three methods for unloading materials from the hopper of a bucket elevator: centrifugal, gravity, and mixing. The type of unloading method depends on the speed, radius, and size of the hopper of the driving drum (sprocket). To clarify the relationship between them, first analyze the stress environment of the materials in the hopper.
The loading and unloading of bucket elevators have a significant impact on their working environment and productivity. The requirements for loading and unloading are: uniform loading and unloading volume that is necessary for productivity; When the hopper is wound onto the drive drum (sprocket), the material can accurately enter the discharge chute without spilling back into the loaded branch or losing into the unloaded branch; During the material unloading process, the vast majority of them do not hit the head cover; When the star shaped unloader accepts deep or shallow buckets, the material does not collide with the hopper in front during the unloading process. These requirements should be carefully considered during the debugging and acceptance of the hoist.
When the hopper moves up at a constant speed in a straight section, the material is only subjected to the action of gravity mg. After the hopper wraps around the driving drum, it moves around the center of the reverse rotation (the axis of the driving drum), and the material is simultaneously subjected to the action of gravity mg and centrifugal force mw2r. The point where the line of action of the combined force of gravity and centrifugal force intersects with the vertical line at the center of the drum is called vertex p. The distance from vertex p to the center of the reversal propagation is called the polar distance h. The size of the polar distance h is only related to the rotational speed of the driving drum, and is independent of the material and its position. When the speed of the driving drum is fixed, h is a constant value, and the position of the vertex p is firm and stable. If the rotational speed n increases, the pole distance h will decrease, and the ratio of centrifugal force to gravity will increase; On the contrary, as the polar distance h increases, the ratio of centrifugal force to gravity decreases. The unloading method can be determined decisively based on the size of the extreme distance h.
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Guangdong bucket elevator m.e-testing.net.cn