Vibrating screen is widely used in coal, chemical industry, metallurgy, ports, water conservancy and electricity industries, an important equipment to complete a variety of different processes. In coal preparation plants and screening plants in the coal industry, screening operations are mainly used in raw coal preparation and product disposal, playing an important role in realizing the rational utilization of coal resources, protecting the environment and creating economic benefits for coal enterprises . The application history of shale shaker in the coal industry can be traced back to the 1960s. On the basis of absorbing foreign experience and independent innovation, the shale shaker has been applied both in design technology, manufacturing technology, variety specification, technical performance and structural strength Has been greatly improved, but there are also shortcomings, the following analysis of its application status and trends. 1, the status quo of coal shaker Shaker according to whether it is close to or away from the resonant frequency is divided into resonant screen and inertial shaker. Currently in the coal industry screening operations, widely used is the inertia shaker, according to the screen when the movement characteristics of the track, the inertia shaker is divided into circular shaker and linear shaker. Circular vibrating screen is mainly used to prepare for screening and final screening; linear vibrating screen is mainly used for dehydration screening, desliming screening and sieving screening. Circular vibrating screen in coal production has been in use for more than 40 years, initially mainly eccentric and simple inertial. Eccentric vibrating screen is not completely elastic support, so that the dynamic balance of the vibration system is not good, the dynamic load to the foundation is large. The simple inertial vibrating screen drive belt drive center is not fixed, poor running stability, transmission belt life is low, so the current use of circular vibrating screen is mainly self-centered, and the structure of the exciter mostly for the pulley Eccentric exciters, mainly because of its simple spindle structure, manufacturing easy. Linear vibrating screen is developed on the basis of circular vibrating screen, also known as biaxial inertial vibrating screen. Initially for a single motor drag, gear forced transmission, so that the relative rotation of the biaxial synchronization generated directional excitation force. As in this work environment, the gear lubrication and sealing problems, affecting the service life, so the current use of mostly double motor drag, no forced transmission of linear shale shaker. Shaker at this stage deficiencies mainly in the following areas: (1) The poor reliability is mainly manifested in the early failure of the key components such as screen frames and exciters, and high failure rate. As the shaker in the washing process system several aspects of work, the failure is bound to cause the entire process system to stop running. According to statistics, currently well-known foreign brands of vibrating screen, the normal operation time is generally above 3000h, overhaul to ensure that more than 20000h, while the reliability of domestic vibrating screen most unsatisfactory. By comparing foreign products, the performance of the original product is better, while the reliability of the domestic product is poor. This shows that manufacturing process control has an important influence on the reliability of shaker. According to statistics, among the main causes of failure, product manufacturing problems account for about 60% -64%. Other items that cause failure rates are relatively close. (2) bearing easy fever Vibrating screen bearing in the process of work, the inner ring to withstand a constant centrifugal force, and the outer ring was fluctuating cycle load, so the load is large, easy to heat, resulting in low life, which has become the shale shaker manufacturer and User headache over the years the general problem, but also the vibration screen parameters to strengthen the constraints. According to statistics, the majority of vibrating screen bearing life is less than 4000h. The main reason is that the material and structure of domestic bearings are affected by the former Soviet Union, the bearing capacity is low, the vibration-resistant ability is poor, so the effect on vibration sieve is not satisfactory. Foreign products use more dedicated vibration-resistant bearings, the working life of up to 20000h. At present, there is no vibration-resistant bearings, vibrating screen manufacturers use foreign bearing products, in order to improve their product reputation is feasible. Another manufacturer for ease of handling, changing the bearing and mounting hole with the level, resulting in loose with too much, but also cause the bearing life is one of the short reasons. (3) Large noise Currently made domestic shale louver noise is generally larger, usually above 96dB, resulting in poor working environment for workers, but also can not hear the abnormal sound of equipment. The main sources of noise detected are the vibrations of the screen frame side and bearings. In addition the transmission gear, sieve plate, exciter box, damping spring and the friction between the bearings, belts, etc. will have a greater noise. Therefore, its noise control requires comprehensive noise reduction to achieve better results. After testing, such as in the side of the screen box, inlet and discharge port affixed rubber plate, which can effectively inhibit the vibration of the side panels to reduce radiation noise; between the inner and outer bearing damping process can reduce the vibration of the bearing And reduce bearing noise; steel sieve can be replaced by a small modulus of elasticity, low impact noise polyurethane sieve and so on. (4) poor manufacturing accuracy of the formation of the product has an important role. Usually a product's success accounted for 70% of its design, and manufacturing accounted for 3 percent. However, for shale shakers, past experience has shown that at least 50% of manufacturing is done. Among them, the problems of manufacturing materials, manufacturing technology and production equipment are the main reasons that cause the gap between China's shale shaker and internationally renowned products. The specific performance of the entire screen frame member geometry irregularities, defects, rough processing, large welding deformation. Caused by this phenomenon also with business management is not in place. (5) Weak Manufacturing Capacity of Large Sieve Machine With the construction of large-scale coal preparation plant and the re-expansion of old coal preparation plant, the requirements of large-scale vibrating screen are getting more and more urgent, but this demand contradicts the manufacturing capability of the vibrating screen manufacturer . At present, most large-scale linear screens above 27m2 still need to be imported from abroad. Domestic manufacturers have introduced manufacturing technology of large-scale screens from abroad, but the results are not satisfactory. The main problems lie in the lack of key equipment and development capabilities for making large screening machines, making it difficult to guarantee the structural strength of the screening machines, resulting in low manufacturing accuracy and low service life. (6) complex replacement parts As vibrating screen work characteristics, such as the screen, bearings and other parts to be regularly replaced. Domestic screen parts replacement generally time-consuming and labor-intensive, affecting production. Foreign brands of screen machine is doing better, such as the screen is pressed with a hydraulic system, the replacement is only hydraulic system can be completed to facilitate the use and maintenance of equipment. 2, coal shale trend With the development of coal preparation plants, the variety and quality of the shaker rising demand, so that the development shaker raised to a new stage of comprehensive screening machinery development status of coal with a screening machine has the following development trend. (1) Standardization, serialization and generalization mainly include the standardization, serialization and generalization of vibrating screen varieties, vibrators, screen frame side panels, sieve trays, beams and transmission shafts. This is an easy way to design, organize specialized production, ensure quality and reduce costs. (2) To Large-scale Development The modernization of industry impels enterprises to expand their scale and greatly increase their production capacity. In the past, the capacity of coal preparation plant was 200-300 t / a is large, and now the production capacity of 12 million t / a coal preparation plant is not uncommon. Therefore need to deal with large capacity, high efficiency sieving screening machine with matching. With the introduction of dynamic design methods and the modernization of manufacturing methods, the structure of large screen machines will become more rational and the deadline for trouble-free operation will be further extended. (3) to the development of high vibration intensity that is to improve the vibration parameters of the shaker, they have a significant impact on the handling capacity of the screening machine, screening efficiency. In addition to the high-frequency screen at home and abroad advanced sieve machine vibration frequency is 980r / min, vibration intensity of 4.5-7 Portable Car Lift,Hydraulic Car Lift,Car Lift For Garage,Car Scissor Lift Wuxi Golden Boat Car Washing Equipment Co.,Ltd , https://www.carwashauto.com