Choose the right type of shaker

Although the screening effect mainly depends on the nature of the material being screened, different types of screening equipment can be used to obtain different screening results for the same material. For example, the screening efficiency of the fixed sieve is low, and for the moving sieve, the screening efficiency is related to the movement form of the sieve surface. On the sieve surface of the sieve, the particles are shaken in the direction close to the vertical sieve sieve on the sieve surface. The higher the vibration frequency, the better the screening effect. On the screen surface, the particles mainly slide along the screen surface. Because the shaking frequency of the shaking screen is lower than the frequency of the vibration screen, the screening effect of the shaking screen is poor; The sieve sieve is easy to block because of the sieve surface, so the screening efficiency is low. Therefore, the type of vibrating screen should be reasonably selected according to the nature of the material in order to maximize work efficiency.

In order to increase the working efficiency of the vibrating screen, it is also necessary to use a larger mesh size, a larger effective screening area, and a higher rate of opening and sieving of the mesh surface as required. Non-metallic screen surface, and choose the appropriate shape of the screen to improve the material through the sieve capacity and work efficiency.

Reasonable choice of vibration motor and adjustment of exciting force

The reasonable selection of vibration motor is one of the key links that affect the screening performance, and the size of the excitation force is the main factor that affects the productivity of screening.

1) Selection of vibration motor As the vibration source of the vibration screen, the vibration motor should have the advantages of reasonable design, simple structure, compactness, high excitation efficiency, energy saving, and convenient installation and debugging. The selection of vibration motor should specifically select the operating frequency, maximum excitation force, power and so on. The rotational speed of the vibration motor should be close to the operating frequency; the maximum excitation force must be within the synthetic excitation force of the selected motor; then the power of the vibration motor is selected according to the selected operating frequency and the maximum excitation force.

2) Adjustment of the exciting force The productivity of the vibrating screen has an exponential relationship with the exciting force. The increase of the exciting force causes a rapid increase in productivity, and the clogging rate decreases rapidly with the increase of the exciting force. The increase of the exciting force makes the vibration intensity increase, the force of the screen facing the material increases, the material moving speed increases, the productivity increases, and the blocking rate decreases. The excitation force has a certain influence on the passing rate and the crushing rate of the sieve, and its variation pattern is wavy. When the excitation force is too small, the pass rate and the crushing rate have a poor effect; when the excitation force is too large, the friction of the eccentric mass at both ends of the shaft of the vibration motor will increase, and in the case of high-speed rotation, the motor is easily damaged and the motor is reduced. The service life, so a reasonable adjustment of the size of the exciting force is very important. The exciting force of the vibration motor is the centrifugal inertia force generated by the eccentric block that rotates at a high speed. By changing the eccentricity and changing the amplitude of the exciting force, the effect of adjusting the exciting force can be achieved.

Improve the screen movement

The movement of the screen surface has a great influence on the working efficiency of the screen. The ideal screen surface movement is:

1) The amplitude of the vertical direction of the material end of the sieve surface should be greater than the vertical amplitude of the discharge end. This is because the large vertical amplitude of the material end of the material can effectively stratify the thicker material at the end, and at the same time, the excess material at the end can be quickly spread to the middle of the screen surface by means of the tilt angle so that the fine material is relatively thin. The material layer in the layer penetrates through the sieve, thereby improving the practical use efficiency of the sieve surface; when the material reaches the discharge end, the material has been divided into layers, then only a small vertical amplitude is needed to ensure the fine material With good sieve conditions, too much vertical amplitude can disrupt the screen-through environment of fines.

2) along the length of the screen surface, starting from the end of the material, the material movement speed should be a decreasing state. This is because the moving speed of the material is decreasing, and the material layer can maintain a certain thickness on the entire screen surface, so that the fine material is layered through the screen on a relatively longer range of the screen surface, and the actual use area of ​​the screen is increased. The sieve screen along the screen length direction tends to be uniform, fully exerting the screening potential of the screen surface.

The equal-thickness and dual-frequency vibrating screens developed in recent years have overcome the disadvantages of the constant amplitude of the entire screen surface of the ordinary vibrating screen and the low unit screening capacity, so that the feed end has a larger amplitude, and the discharge end has The same amplitude as the ordinary shaker, thus improving work efficiency. Recently, some scholars have obtained a new type of vibrating screen—a complex motion track shaker—by transforming a round vibrating screen or a linear vibrating screen. It has a simple structure, low power consumption, and high work efficiency. The sieve is circularly moved on the screen surface of the human material end, and the central screen surface is moved in an elliptical manner. At the discharge end, an arc of an approximately straight line is moved, and the movement path of the screen surface along the screen length direction changes from point to point along the screen length. The direction of the material movement speed is decreasing. It not only improves the screening efficiency and work efficiency, but also reduces the production cost. It is an ideal screen surface movement method.

The use of a non-metallic screen mesh with a thin flexible screen as the screen base is very advantageous for improving the working efficiency of the vibration screen. This kind of screen is generally made of rubber or polyurethane material, which can reduce the adhesion between the screen surface and the screened material, make the material produce secondary high-frequency vibration, avoid the clogging of the screen hole, and enhance the transparency of the material. Sex, and can ease the mechanical effect of the screened material on the screen surface, compared with the wire mesh can withstand greater amplitude vibration. Non-metallic screens have the following advantages:

1) Improve screening efficiency. It is about 20% more efficient than metal mesh screening.

2) Good wear resistance and long service life. Its average life span is more than 25 times that of metal screens.

3) Reduce installation time. Improve the equipment operation rate D. Because the service life of the non-metal material screen is greatly extended, the number of replacement of the screen surface is reduced, and the operating rate of the metal screen equipment is generally increased by 15%.

4) Reduce noise and improve working environment. In addition to the resonance of the screen mesh in the metal screen during operation, the mesh also generates some vibrations. This phenomenon is more obvious after wear, and the noise of the material on the surface of the box and the vibration of other components make the noise higher. The non-metallic material screen as a whole screen, a certain buffer, can reduce the noise of about 20dB (A).

Multi-feed method

Ordinary vibrating screen is a way to feed, after the material is given to the screen surface, most of the materials less than the separation granularity in the feed end, quickly through the sieve hole to become the product under the screen, and from the discharge end of the l/3-1/ In addition to continuing to play a certain role in screening, the screen surface of the 2 mainly plays a role in transportation, and thus the utilization rate of the screen surface is not high. If multiple feeds are used, it is equivalent to increasing the width of the screen surface and reducing the thickness of the material layer given to the screen surface, which is beneficial for the fine materials to quickly contact the screen surface through the screen holes, and can fully utilize the screen surface. Reducing the unnecessary transportation distance of coarse particles, thereby improving its work efficiency.

Strengthen operation management

Correct operation and careful maintenance are also effective ways to improve the working performance of the shaker. When the vibrating screen is working, the feeding materials are required to be uniform, continuous, and appropriate, so as to ensure that the material is evenly distributed along the entire width of the screen surface, so as to facilitate the penetration of fine particles, thereby obtaining higher processing capacity and screening efficiency. In addition, we must strengthen the maintenance and maintenance of the screening machine, clean up the screen surface in time, and repair and replace the damaged screen surface to ensure the equipment is in good condition.