Design and development of double rotor crusher for

Design and development of internal screening double rotor crusher

in China's economic construction, especially in the process industry and capital construction, all kinds of crushing equipment are widely used, such as building materials, mining, metallurgy, chemical industry, construction, etc. Only more than 4500 cement plants in the building materials industry have nearly 20000 sets of crushing equipment. The performance and functions of these crushing equipment not only directly affect the output and energy consumption indicators of the enterprises, but also affect the relevant economic indicators of their corresponding industries. For this reason, many scientific and technological workers in China have made tireless exploration, made many achievements and produced various forms of crushing equipment, and achieved certain results in reducing consumption. However, the expected effect is not very ideal, and various forms of crushing equipment have their own advantages and disadvantages. In view of the problems existing in the existing crushing equipment, the author, together with Professor Huang Zhichu (doctoral tutor) and Dr. Wu Jingbing (Doctor) of Wuhan University of technology, has jointly developed an internal screening double rotor crusher to meet the needs of the development of production technology in relevant industries<------- Professor xiepengcheng/doctoral tutor, School of electrical engineering, Beijing University of chemical technology/p>

1 characteristics of crushers in service in China at present

1.1 jaw crusher: driven by eccentric shaft, the moving jaw moves back and forth regularly, and the materials are crushed between the fixed jaw plate and the moving jaw plate. Jaw crusher is simple in structure, easy to manufacture and maintain, solid in body and large in feeding port, which can break high hardness materials

1.2 hammer crusher: the hammer is connected to the rotor, and the high-speed rotating rotor drives the hammer to impact the block and break the material. Hammer crusher has simple structure, large crushing ratio and high production capacity

1.3 impact crusher: materials are hit on the hanging impact plate by the high-speed rotating impact plate. When falling, they impact each other with the materials hit later and collide repeatedly to get broken. The impact crusher has simple structure, large crushing ratio, high production capacity and fine products

1.4 vertical shaft crusher: the materials enter the crusher cavity axially and fall onto the throwing plate on the high-speed rotating rotor. The materials are thrown out at high speed through the throwing plate, collide with the impact plate built in the shell, and rebound into the hammering area. Because the impact plate has an inclined impact surface, the materials are hit and counteracted by the plate hammer in the hammering area according to the "Z" line, and finally the materials are discharged out of the cavity. Vertical shaft crusher has large crushing ratio and high production capacity

1.5 impact crusher: the material enters the crusher cavity axially, is thrown out at high speed by the extremely high-speed rotating rotary table, and collides with the impact wall plate inside the shell. Broken by high-speed impact. Impact crusher has large crushing ratio and high production capacity

2 existing problems and improvement direction of crushers in service in China

2.1 existing problems

2.1.1 jaw crusher: the crushing ratio is not large; It is not suitable for flaky materials to be broken; The crushing is reciprocating and inefficient; When wet and viscous materials are broken, the discharge port is easy to be blocked

2.1.2 hammer crusher: the hammer head, grate bar and guard plate wear fast, and the dust is large during production

2.1.3 impact crusher: the rotor is easy to be damaged in case of large material; Poor anti blocking performance; There is material short circuit

2.1.4 vertical shaft crusher: the hammer head and guard plate wear fast; Large dust and short circuit of materials

2.1.5 impact crusher: the rotor wears fast; The temperature of the bearing rises quickly, the dust is large, and there is a material short circuit

2.2 improvement direction

in view of the above analysis, we believe that it is necessary to change the low efficiency, high energy consumption, easy wear and dust of the traditional crusher to replace the brominated flame retardant nbsp; The exterior wall thermal insulation materials are faced with the phenomenon of large new selection and short connection of materials. The following problems must be solved: the correct selection of wear-resistant materials and impact angle; Improve the probability of material self collision; Reasonable allocation of motor power; Effective use of dust removal devices; Setting of screening system; Selection, lubrication and cooling of bearings; Wait

3 internal screening double rotor crusher

the internal screening double rotor crusher has made meaningful attempts in the above aspects that need to be improved and achieved ideal results

3.1 the structure of the internal screening double rotor crusher

is shown in the figure. Its main components are composed of feed hopper (feed screening), discharge tray, inner rotor (impact plate hammer), outer rotor (impact plate), discharge screen, lower hopper, dust pipe, support shell, etc. The transmission system is composed of motor I, rubber block coupling, motor II, V-belt, V-belt pulley, etc. The motor II and the support shell are installed on the base. The machine has novel design conception and reasonable structure

1. The configuration of motor I is extremely outstanding in the medical industry and automotive field. 2. Feeding device (including feeding screening) 3. Dust discharge cylinder 4. Inner rotor (including impact plate hammer)

5. Outer rotor 6. Lower hopper (including discharge screening) 7. Simplified 8. Motor Ⅱ 9. Belt pulley

3.2. Working principle

the two motors of the machine are placed at the top and bottom respectively, The top motor is directly quenched through the rubber block coupling to shape the plastic extruded layer, which is beneficial to the dynamic spreading disc and inner rotor (impact plate hammer). The bottom motor drives the outer rotor (reaction plate) through the belt pulley and V-belt. When working, the inner and outer rotors rotate at a high speed in the opposite direction. When block materials (such as limestone, clinker or other brittle blocks) fall through the feed port, enter the distributor and inner rotor area after pre screening of the feed, the materials will be scattered by the distributor and impacted by the impact plate hammer in this area, and will be thrown out of the rotor area at a high speed (this area is composed of read parabola impact plate). At this time, the materials will be strongly impacted by the parabola impact plate of the outer rotor with high speed and opposite rotation direction, The angle of attack during the reverse impact is 75 ° -78 °, and the brittle material is rapidly broken. At the same time, the material at the gap between the inner and outer rotors is sheared or bounced to meet with the subsequent high-speed stones, resulting in high-speed collision and crushing, and then it is thrown from the outer rotor impact plate to the inner rotor at high speed, and collides with the impact plate hammer again. The materials are crushed or powdered by strong impact, shearing and mutual collision in the above three areas. After screening by the discharge screen, the qualified products are discharged through the discharge 121 on the bottom. Large pieces of materials are driven by centrifugal force and then enter the crushing area to be hit by the impact plate hammer and then crushed again

4 main performance characteristics of internal screening double rotor crusher

4.1 good crushing effect. The particle size of finished products of traditional crushers above 15mm accounts for 70%, and that below 15mm accounts for 30%. The particle size of the internal screening double rotor crusher is 100% below 1mm and 85% below 0.5mm

4.2 the crushing particle size is controllable and adjustable. By adjusting the specification of the sieve plate, the discharge particle size of the material can be adjusted to meet the user's requirements for different particle sizes

4.3 sets have high output. The unit hour output of the internal screening double rotor crusher is 1.5 ~ 2 times that of the traditional crusher, and its output of fine powder can account for about 70%, which can not be achieved by the traditional crusher

4.4 significant energy-saving benefits. The energy consumption output ratio of the traditional crusher is greater than 2kw/t, while the energy consumption output ratio of the internal screening double rotor crusher is 1kw/t. For a cement plant with an annual output of 200000 tons, the annual power consumption of a single crusher can reach 100000 kwh, and the energy-saving benefits are extremely considerable. Secondly, the crushing effect is good. The particle size after crushing can be controlled below 5rrm by 100%, so it is easier to grind. The energy consumption of the whole grinding system can be reduced by 20~30%, and the output of the ball mill can be increased by%

4.5 low equipment noise. The machine is designed to achieve the purpose of crushing by the self phase high-speed impact and collision of materials in the shell, avoiding excessive direct hammering and extrusion of the crushed workpiece, and greatly reducing the working noise

4.6 less dust. Due to the design of high-speed rotation in the opposite direction of the inner and outer rotors, the whirling air flow is formed in the equipment shell. Moreover, due to the setting of the air extraction pipe, the air flow of the crushed material dust rises and does not spread to all directions, which is conducive to centralized dust removal and dust reduction

4.7 the equipment covers a small area and is light in weight. Compared with the impact crusher, the machine occupies a smaller area, only about 2M2; The weight of the equipment is also greatly reduced

5 conclusion

the internal screening double rotor crusher scientifically integrates the functions of brittle boring impact crushing, impact crushing and dynamic screening. Its structure is reasonable and its design is novel. It is in the leading position in China in terms of improving the crushing effect of materials and the hourly output of equipment, especially in controlling product strength and reducing energy consumption. It provides an advanced equipment for China's process industry and basic construction, such as building materials, mining, metallurgy, chemical industry, construction and other industries. Now, many domestic enterprises have started to use this equipment. We expect that with the further improvement of product quality and product design, the product will be gradually popularized and applied throughout the country. (end)