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.
Causes and measures:
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.
Causes and measures:
The common transmission faults of the circular vibrating screen include coupling wear, break of the joint bolt, crack of protection cylinder, bearing damage of belt pulley bearing base and belt tear.
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.
Causes and measures:
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.
Causes and measures:
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.