The use of dewatering screen is essential in mining machinery. Dewatering screen is widely used in tailings dry discharge, concentrate dewatering, refining mud slurry concentration, debris removal, carbon slurry separation and other industries. The following is about the working principle and performance advantages of dewatering screen.
Nowadays, the coal slurry content in the products of coal industry increases and contains a large amount of water, which makes the dewatering of coal slurry difficult. Previously, the water treatment of coal slurry investment is large, which is not conducive to the control of production costs, but now the application of high-frequency dewatering vibrating screen, which has a large handling capacity, simple process system and other characteristics can be very good for the dewatering of coal slurry. High-frequency dewatering sieve screen is a kind of vibrating screen mainly characterized by high frequency and high vibration intensity, which is suitable for wet separation and solid-liquid separation of fine-grained materials.
Working principle of high frequency dewatering vibrating screen
The working principle of high-frequency dewatering vibrating screen is to use high-frequency vibration to destroy the surface tension of the slurry, and fine-grained materials will be high-speed oscillation on the screen surface, thus accelerating the precipitation of the large density minerals, increasing the probability of less than the separation of particle size of the material and sieve hole contact, double vibration motors or flange-type vibration exciters, two motors outside the trailing to do the opposite direction of the self-synchronous rotation, so that the sieve body along the straight line direction of the cyclic reciprocating motion, fine-grained materials can quickly pass through the screen hole to be screened out to achieve the purpose of screening and dewatering. Fine-grained materials can be quickly screened out through the sieve holes, in order to achieve the purpose of screening and dewatering.
Due to the high frequency sieve adopts high frequency, on the one hand, it destroys the tension on the surface of the slurry and the high-speed oscillation of fine-grained materials on the sieve surface, accelerates the precipitation of useful minerals with high density, and increases the probability of contact between the materials smaller than the separation granularity and the sieve holes. Thus creating a better separation conditions, so that less than the separation size of the material, especially the specific grains and slurry through the sieve holes together to become the product under the screen.
Workflow of high frequency dewatering vibrating screen
1、Symmetrically mounted on the vibration beam of the two same parameters of the vibration motor synchronous reverse rotation, each produces equal size centrifugal force, the two forces in the vertical vibration direction of the opposite force to cancel each other;
2、 In the parallel vibration direction of the force is consistent with each other to form a linear vibration force, linear vibration force cycle continuously on the sieve body, so that the sieve body in the buffer spring vibration;
3、 At the same time, the buffer spring reduces the dynamic load of the sieve body on the sieve machine support base, the sieve body drives the sieve surface synchronized vibration, the force will be transmitted to the sieve material;
4、 The impact of the material in the screen surface thrown up forward dewatering, the material continuously from the feed chute input, through the screen surface for dewatering, under-screen material discharged into the under-screen chute, screen material discharged into the discharge chute.
Motion characteristics of high frequency dewatering vibrating screen
According to the mechanical structure and process parameters, the vibrator of the high frequency dewatering vibrating screen is arranged above the center of gravity of the sieve box, and this arrangement makes the sieve machine trajectory in the feeding end of the ellipse, the middle of the circle, and the discharging end of the ellipse, so that the movement of high frequency dewatering vibrating screen movement trajectory is ellipse – ellipse.
Because of this unique movement characteristics of high frequency dewatering vibrating screen, the long axis of the ellipse at the feed end and the sieve and the angle into an acute angle, the long axis of the ellipse at the discharge end and the sieve surface angle into an obtuse angle. This makes the material in the feed end of the movement speed is greater than the discharge end of the movement speed, to ensure that the material in the sieve and the feed end of the sieve can be quickly loosened, the material layer is thin, so that the fine-grained materials as soon as possible layered contact sieve and penetrate the sieve, the water viscous membrane rupture dehydration; and the discharge end of the material speed is small, you can prolong the material in the sieve surface of the dewatering time, and thus increase the effect of dewatering. The sieve machine has this characteristic, strengthen the dehydration effect.
Advantages of high frequency dewatering vibrating screen
1、Simple and compact structure, high rigidity, high strength, balanced distribution of force;
2、 The service life is often, the overall service life of the vibrating screen equipment is up to 5 years;
3、 The screen can be made of wear-resistant polyurethane material, long service life, high screening efficiency;
4、Low working noise, the noise is lower than 75 dB, smooth operation;
5、Light weight, low power consumption, high vibration intensity (9-12mm), high screening efficiency;
6、A full range of varieties, can fully meet the different material characteristics and handling capacity of the screening process requirements;
7、The sieve machine operation and maintenance is simple, cost-effective, adequate spare parts, timely and thoughtful service. Below we will introduce about the maintenance of dewatering vibrating screen.
Maintenance of high frequency dewatering vibrating screen
1、Check whether the bolts of each part are loose at any time, and whether the screen frame collides with the chute and so on.
2、According to the nature of the ore and material requirements, adjust the excitation current (amplitude), in order to make the sieve machine in the premise of high efficiency to complete the task, can do the excitation current premise experiment.
3、Electromagnetic exciter and control box should be careful to prevent water, so as to avoid short circuit. To cover the shaker with a rubber plate to prevent water and slurry from falling in, constituting a short circuit and blocking the air gap.
4、The normal operation of the equipment, should often observe the sieve to the concentration of ore, so that the concentration of moderation in about 40%, in order to improve the grading efficiency.
5、When the fabric hopper to give into the sieve slurry flow shot too far, should be real-time adjustment of the status or angle of the screen frame, so as not to affect the grading efficiency.
6、Because the sieve grading efficiency is high, the dehydration function is good, and the concentration of the sieve amount is high, which makes the slurry in the sieve amount chute has poor mobility, and it should be equipped with a water pipe.
In summary, the working principle of high frequency dewatering vibrating screen is to use high frequency vibration to destroy the surface tension of the slurry, accelerate the role of large density mineral precipitation, increase the probability of less than the separation of particle size material contact with the screen holes, and the fine-grained material through the holes to be screened. We need to find a suitable vibrating screen model when buying, because different model specifications have different feeding capacity, from ten tons per hour to two hundred tons per hour, according to their own production needs to choose.
FAQs
Why do dewatering screens mix materials？
1、The damage of the sieve: the sieve is a fragile part, so it is inevitable that the sieve will be damaged in the process of use, so that the phenomenon of mixing will occur.
2、Screen frame loose: linear vibrating screen frame is fixed with rivets, the use of a period of time will appear loose, loose will also appear mixed phenomenon.
3、Screen frame fracture: poor quality products, after a period of time will appear after the phenomenon of screen frame fracture. Sieve frame breakage will also lead to screening material mixing phenomenon.
Dewatering sieve plate damage causes and solutions
Reasons for rapid damage of dewatering sieve plate.
1、The screen quality is not qualified. General requirements of the upper screen layer and the lower stress layer fit tightly, if the screen mesh technology is poor, when the screen mesh bottom stress layer fit tightly, the screen mesh layer has no tension, the work of the drilling chip throwing force is greatly reduced, the drilling chip can not be discharged.
2、Screen mesh tension is not enough, resulting in screen mesh vibration, generally along the edge of the screen mesh or the edge of the package broken or broken.
3、The vibration motor steering error in adjusting the vibration motor steering, according to past experience, the operator thinks that as long as the drill cuttings go forward, but this method is not applicable to all vibrators. If the vibration motor is wrongly steered inward, although the ejection angle is 45°, there is the force of the drill cuttings rolling backward, which makes the drill cuttings migrate forward much slower, and stays on the screen for a long time, and even leads to the drill cuttings can not be discharged.
4、many times customers encounter a variety of problems, need to dewatering screen for a long time. May be used for too long is also an important reason for the rapid breakage of dewatering screen.
5、No maintenance. Although sometimes the dewatering screen is damaged due to quality problems is a great concern, but if you buy back the dewatering screen does not carry out maintenance and maintenance, the speed of damage will be accelerated.
The solution of too fast damage of dewatering screen plate.
1、Spray the screen and plugs with water to reduce the stickiness of the plugs, but this method is only applicable to the case where water is allowed;
2、Adjust the angle of the screen mesh at the sand discharge port downward, which is conducive to the use of gravity to remove the rock chips, but it may lead to running slurry;
3、Improve the quality of the vibrating screen pieces produced by the foundry;
4、Change the mesh number of the screen tube or adjust the flow rate of a single screen tube to ensure that the stopping point of the drilling fluid is close to the outlet of the screen tube, so that the drill cuttings can be discharged smoothly under the lubricating effect of the drilling fluid.
5、 Maintenance should be carried out after use, which can play a role in protecting the screen and minimize wear and tear.
