Redhills, Chennai Plot No. 28 & 29, Athivakkam Main Road, Gomathi Amman Nagar, Annex 7 Extension Redhills, Near R. B. Gothi Jain College For Women, Redhills, Chennai - 600052, Dist. Chennai, Tamil Nadu
Screening effect and efficiency of the vibrating screen can affect the output and production efficiency of the whole production line. Here are some reasons that affect the screening effect and efficiency of vibrating screen.
Experiments show that adding surface-active material to water containing material can increase the activity and dispersibility of materials, and improve the screening condition. Besides, using the vibrating screen deck that is made up of non-hydrophilic materials also can improve the screening efficiency.
The soil is easy to knot and lock the mesh in the screening process. Clayey materials and viscous materials can only be screened with large mesh in some special cases. Wet screening is spraying water on the material that is moving along the vibrating screen deck, and pre-desliming before screening.
The particle characteristic mainly refers to the content of various grained materials that have a specific influence on the vibrating screening process. When the difficult screening material is much more than other fractions, the screening process is better. The particle characteristics also include the shape of particles. It is easier to screening for those particles who have close three-dimensional sizes, such as spheres and polyhedrons. In other conditions, it is more difficult to screening for those particles with large different sizes, such as slice, strip and weird shape.
There is no effect on the screening effect if all particles are the same density. However, if the density of coarse and fine particles are different, the situation is totally different. If the coarse-grained density is small, then fine-grained density is large. In contrast, coarse-grained density is larger and fine-grained density is small.
Movement type of vibrating screen deck is related to the looseness of the oversize material layer and the speed, direction and frequency of vibrating screen motion. In the vibrating screen, movement type of screen deck is divided into several kinds of forms: circular vibration, linear vibration and elliptical vibration. Xinhai has developed a series of vibrating screens with high screening quality, such as circular vibrating screen, auto centering vibrating screen, linear vibrating screen.
In general, the screen width directly determines the processing capacity of the vibrating screen. The wider the screen, the larger the processing capacity. The screen length determines the screening efficiency. The longer the screen, the higher the screening efficiency. When the screen length reaches a certain size, the screening efficiency will be rarely increased, or even no longer increases. And if you increase the screen length now, only the size and quality of screen are increased.
Screen slope has a great influence on the screen strength. The larger the screen slope, the smaller particle size, the smaller the screen slope, the larger particle size. In order to exclude oversize material easier, sometimes the screen deck should be installed obliquely. The larger slope, the faster the material layer moves on the screen deck, the greater the productivity. But the time that material stays on the screen deck is shortened, which decreases the screen-penetrating probability and reduces the screening efficiency.
The larger screen, the higher unit area screening efficiency and the higher screening efficiency. In general, the larger the mesh size, the higher porosity of the screen. When the mesh size is certain, the larger porosity of screen is more beneficial to the screening of vibrating screen. However, but the porosity of screen is often limited by screen strength and service life.
For certain screen and raw materials, the operating condition mainly refers to the quantity and mode of feeding. Continuous and even feeding is the best feeding method. In addition, please timely clean and maintain screen deck, which is also conducive to screening effect of the vibrating screen.
The vibrating screen is a very important auxiliary equipment in the mine production, which will directly affect the normal operation of the production line if the vibrating screen fails. As a common type of vibrating screen, what are common problems of the circular vibrating screen (also known as the round vibrating screen) in the daily operation? And how can we solve them? This paper analyzes the causes of five common problems of circular vibrating screen and puts forward countermeasures.
In general, the circular vibrating screen is mainly driven by an electric motor with an eccentric mass vibrator to produce vibration. In the vibrating process, the shaft is the key component to drive the vibration of the circular vibrating screen. Therefore, the break of the shaft is a common fault in practical use. Once the shaft failure occurs, the circular vibrating screen will immediately stop working, and its maintenance is more complex, which must be given high attention.
The shaft of the circular vibrating screen is a kind of metal material, which is subjected to the resultant torque and repeated impact force for a long time. Under the action of long-term impact moment, the material inside the shaft will gradually fatigue, and when the fatigue limit is reached, the fracture phenomenon will occur. In addition, the torsion strengths of different materials are greatly different. If the material is poor, it will inevitably lead to low bending strength and fatigue limit, which will easily lead to failure.
It is recommended to purchase the circular vibrating screen from the normal manufacturers, ensuring that the selection of components is reasonable. At the same time, it is strictly prohibited to start the circular vibrating screen with the material, ensuring that the circular vibrating screen is only started under the premise of no material; Strengthen the daily maintenance and inspection. Check the shaft regularly, once found bending, deformation and other phenomena, it must be replaced in a timely manner to avoid damage in the transmission process.
If the triangular belt tension of the circular vibrating screen is too large, it will cause the extra bending moment of the axis, thus increasing the synthetic moment. The material stress significantly increases when working, even exceeding the allowable stress of the axis, which will directly lead to the destruction of the axis phenomenon. Therefore, it is necessary to adjust the tension of the triangle belt in time. It is suggested to reduce the tension of the triangle belt as much as possible under the premise of the normal transmission.
The vibrating screen is mainly composed of the vibrator, screen box, support or suspension device, transmission device and other components. In the case of transmission failure, the circular vibrating screen will be unable to use, seriously affecting the normal production. At the same time, the transmission fault of the vibration screen is more complex, not easy to repair.
Therefore, the operators of the circular vibration screen need to regularly carry out the preventive inspection of the transmission part, especially pay attention to the longitudinal and transverse clearance of the bearing, ensuring that the spacing meets the requirements. Besides, the operators need to add the lubricating oil in time for avoiding the serious wear, check the bearing support weekly and add the lubricating oil in time, and observe the operation of the circular vibrating screen. If there is any abnormal situation, it must be stopped and carried out the system inspection for avoiding more serious accidents.
Too high bearing temperature is also a common fault in the use of the circular vibrating screen. Although the too high bearing temperature cannot immediately have a direct impact on the production, the service life of the bearing must be affected under the long-term and continuous high bearing temperature. Therefore, the technical personnel must also attach great importance to this issue.
The long times of working will inevitably produce a certain amount of heat, which in turn promotes the evaporation of the oil, which in turn will further lead to increased friction, making the temperature rise. Therefore, it is necessary to reasonably arrange the running time of the circular vibrating screen, improve the operating efficiency of the equipment, avoid a long time continuous work, and can be closed in time when the circular vibrating screen is not needed.
The lack of lubricating oil will inevitably lead to rising temperatures. It is necessary to check the bearing regularly and add the lubricating oil to avoid the excessive temperature caused by insufficient lubricating oil.
The main factors affecting the aging of the screen surface are the structure, material and tightness of the screen surface. At present, many circular vibrating screens use the polyurethane screen surface.
On the one hand, the anti-aging property of polyurethane itself is not high. On the other hand, if the staff doesn't tighten the screen surface when installing the screen surface, that is, only fix both sides of the screen surface and the middle is not fixed, the screen surface and bracket will constantly collide and rub up and down. Because the screen surface contacts with the material directly during the operation of circular vibrating screen, so the screen surface will produce secondary vibration when the screen surface is not strained and in a loose state, which will cause the wear of the screen surface and accelerate the aging phenomenon of the screen surface of circular vibrating screen.
In this regard, it is recommended to choose the high-quality screen surface, and the operator should check whether the screen surface is loose or damaged regularly. When replacing the screen surface, both sides of the tensioning plate should have the same and uniform tensile force, and the screen surface must be strained. For those screen surface which cannot be used, the operator needs to replace them in time, thus avoiding causing more serious problems.
There are the five common problems of circular vibrating screen, causes and measures. In order to ensure the stable and efficient operation of the equipment, the daily maintenance and maintenance are more important except for selecting the type of equipment that conforms to the mineral processing process. Therefore, it is suggested that each mine owner consult the professional equipment manufacturers when choosing the circular vibrating screen and choose equipment suitable for its own process flow, so as to fundamentally guarantee the normal operation and economic benefits of the whole concentrator.