Tubular mills for clinker grinding in cement industry
The Samara Strommashina plant manufactures industrial mills designed for performing the most complex production tasks. The Strommashina has been developing and selling grinding equipment of various types over 70 years. A motive force in improvement of our grinding equipment (ball mills, hammer mills and bowl mills, vertical rod mills); and design and engineering technologies of crushing and grinding is the indispensable experience which we obtain and competitors we face being the market leaders in this sphere.
One of our profile types of industrial mills is tubular ball mills. Tubular mills are widely used for clinker grinding in cement industry. Such mills are designed for both wet and dry grinding, they can be used in unclosed and closed cycles. The material is fed into the charging funnel and then it is fed into the first drum chamber through a feeder and an auger located in the spigot. The ground material is poured through the intermediate diaphragm slots and wall holes into the collector from which it is fed into separators.
The "oversized" product separated in the separators is fed through air-side conveyors into the second mill section receiver from which the elevator blades feed it onto the guide cone through which the material is fed into the second section.
From the second section the ground material is fed by the blades and auger through the mesh holes through a hollow spigot into a discharge nozzle. Being spilled from the window, the material falls onto the sieve catching the crushed particles of grinding media which are then removed through the nozzle. The finished product is spilled through the sieve and gets into the nozzle from where it is delivered to the storage.
The tubular drum is driven by a synchronous slow-speed motor via a gearbox the output shaft of which is connected with the spigot by spline couplings. Much heat is released during the mill operation. It causes evaporation of water from the material which can decelerate the grinding process. To maintain normal mill operation mode, any contaminated, moist air is permanently drawn from the mill.
hen the mill operates in the unclosed cycle, the opening shall be closed with special covers so that blades could feed the material from the left to the right chamber immediately. The internal surfaces of the left chamber are lined with profiled plates, and smooth plates are installed in the right chamber.
The vibrating conveyor feeds the material is fed into the receiver and further into the mill. The elevator feeds the material ground in the first compartment into the separator. The finished product is removed from the separator into the compressed-air pump which delivers it to the storage.
Any material requiring remilling can be delivered both into the second mill chamber, and to the first chamber inlet by air-slide conveyors. The ground material is fed from the second chamber into the chamber pump through discharging device 8. The flue-gas fan draws the heated moist air from the mill through the shaft. Any contaminated air is purified in dedusting cyclones and electric filter. The product extracted in this process is fed into the chamber pump through air-slide conveyors.
The ball mill calculation is confined to determination of source data for several key parameters. Based on known physical model of balls behaviour in the drum and theoretical trajectory of the ball movement, the optimum and critical drum rotation speeds are determined.
The same principle is used to determine the trajectory of the charged material movement in the drum, and the optimum charge value is derived. In practice, the balls occupy 0.3 to 0.35 of the drum space.
The mill drive power is calculated by determining the energy consumed for drum rotation, ball movement and material transport. During the mill operation energy is consumed for ball lift and transferring kinetic energy to them, as after fall of the ball their circumferential speed is equal to zero, and the balls have to be involved in the movement in each cycle.
Also, the drum and mill assemblies are designed to be strong and durable by plotting load distribution curves, the maximum static and dynamic forces occurring in the mill design are determined.
The Samara Strommashina plant ensures high quality, reliability, ease of use, repairability, competitive prices, uninterrupted supply of spare parts and maintenance service of all our products. These are convincing reasons to buy a tubular mill from us.
All our products are certified, they have permits for use and sanitary-epidemiological conclusion certificates. The original designs are patented.