Construction Principle Characteristics
Shaker construction
The bed surface can be made of wood, steel sand, fibreglass or aluminium, and the slope of the bed surface can be adjusted. The bed surface is equipped with bed bars of different lengths and heights. The length and height of the bars increase gradually from the feed side to the coal side. The height of each bed bar is the highest from the head end and gradually decreases to zero towards the tailings end.
Bed in the bed driven by the head, for longitudinal reciprocating asymmetric movement, the bed in front of the forward, its speed from slow to fast, and then quickly stop (with a large backward acceleration, the particles get a large forward inertia force). In the backward, its speed from zero rapidly increased to the maximum value, and then slowly reduced to zero (forward acceleration is small, the particles backward inertia force is small).
Shaking bed sorting principle
(1) the water flow over the bed strip formed when the water jumps and rising water flow stratification, the bed surface of the intense shaking to strengthen the perturbation of the inclined water flow, stratification results in low-density fines on the high-density coarse grains in the next, while the coarse grains of low-density and high-density fines are basically in the state of mixing with each other.
(2) bed shaking produced by the separation effect, bed shaking caused by the bed loose, the same density conditions, fine particles have a greater pressure, fine particles can pass through the gap between the coarse particles into the lower bed, high-density fine particles have a greater pressure, as a result, high-density fines than low-density fines drilling down to a deeper level. In the process of sorting, the above two kinds of sorting effect exists at the same time, the separation of stratification plays a dominant role, the rising water flow can make the mixing of heavy products in the low-density material to get better separation
(3) the lateral movement of the ore particles in the bed surface, the lateral movement of the ore particles is due to the transverse flow of water driven by the transverse flow layer along the thickness of the velocity distribution is greater than the upper layer of the lower layer, and the velocity distribution is greater than the upper layer of the lower layer.
Distribution of velocity along the thickness of the transverse flow layer is greater than the lower layer, due to the obstruction of the bed bar, the upper layer of material by the transverse flow of the role of the larger, therefore, the upper layer of low-density material particles have a greater than the lower layer of high-density material particles of the transverse velocity.
(4) the longitudinal movement of the ore particles in the bed, the asymmetric shaking of the bed so that the ore particles intermittently move forward, only the bed to the inertial force of the ore particles is greater than the friction between the ore particles and the bed, the ore particles can begin to make the bed for the relative sliding, the bed.
For low-density ore particles, in the forward, backward and backward, forward two turning stages of inertia may be greater than its friction with the bed, resulting in back and forth sliding. However, the inertia force for forward movement is always greater than that for backward movement, and the overall movement is forward.
For high-density ore particles, it is only in the bed from the forward to the backward stage of the inertia force obtained to be sufficient to make it slide. In addition, the lower layer of high-density ore particles close to the bed, can get a larger inertia force, the more located in the upper layer, the looser the bed, the smaller the inertia force obtained by the ore particles. As a result, the longitudinal movement speed of the high-density ore particles is greater than that of the low-density ore particles.
