Ball mill is the key equipment for crushing materials after they are crushed. This type of mill is loaded with a certain number of steel balls as grinding media in its cylinder.

　　Ball mill is widely used in cement, silicate products, new building materials, refractory materials, fertilizers, black and non-ferrous metal beneficiation and glass ceramics and other production industries, dry or wet grinding of various ores and other grindable materials. Ball mill is suitable for grinding all kinds of ores and other materials, which is widely used in mineral processing, building materials and chemical industry, etc. It can be divided into two types of dry and wet grinding. It can be divided into two types: dry type and wet type. According to the different discharge methods, it can be divided into two types: lattice type and overflow type.

　　Introduction

　　Ball mill is the key equipment for crushing materials after they are crushed.

　　Ball mill is one of the widely used high-fine grinding machines in industrial production, and there are many kinds of ball mills, such as tube ball mill, rod ball mill, cement ball mill, ultra-fine laminating mill, hand ball mill, horizontal ball mill, ball mill shaft tile, energy-saving ball mill, overflow ball mill, ceramic ball mill, lattice ball mill.

　　Ball mill is suitable for grinding all kinds of ores and other materials, which is widely used in mineral processing, building materials and chemical industry, etc. It can be divided into two types of grinding methods: dry type and wet type. It can be divided into two types: dry and wet grinding. According to the different ways of ore discharge, it can be divided into two types: lattice type and overflow type. According to the shape of the cylinder, it can be divided into four types: short cylinder ball mill, long cylinder ball mill, tube mill and cone mill.

　　Working Principle

　　Ball mill is composed of horizontal cylinder, inlet and outlet hollow shaft and grinding head, etc. The cylinder is a long cylinder, which is equipped with grinding body, the cylinder is made of steel plate, there is a steel liner fixed with the cylinder, and the grinding body is generally made of steel balls, which are loaded into the cylinder according to different diameters and a certain ratio, and the grinding body can be used as a steel section. According to the particle size of the grinding material to be selected, the material from the ball mill feed end of the hollow shaft into the cylinder, when the ball mill cylinder rotation, the grinding body due to inertia and centrifugal force, friction, so that it is attached to the cylinder liner by the cylinder to take away, when brought to a certain height, due to its own gravity and was thrown down, the falling grinding body as a projectile as the material in the cylinder body to the crushing.

　　Materials from the feeding device through the feeding hollow shaft spiral uniformly into the first bin, the bin has a stepped liner or corrugated liner, containing various specifications of steel balls, the cylinder rotation generates centrifugal force to bring the steel ball to a certain height and then fall, the material to produce heavy impact and grinding effect. After the material reaches rough grinding in the first warehouse, it enters into the second warehouse through the single-layer partition board, which is set with flat lining board and steel balls inside, and further grinds the material. The powder is discharged through the discharge grate plate to complete the grinding operation.

　　Cylinder in the process of rotation, the grinding body also has the phenomenon of slippage, in the process of slippage to the material to grind, in order to effectively utilize the grinding effect, the material size of the larger general twenty mesh when grinding fine, the mill cylinder with a silo partition plate separated into two sections, that is, to become a double warehouse, the material into the first warehouse when crushed by the steel ball, the material into the second warehouse when the steel section of the material to be ground, the mill qualified materials from the The qualified material is discharged from the hollow shaft at the discharge end. When grinding the materials with small feeding particles, such as sand slag and coarse fly ash, the mill cylinder may not be equipped with partition boards, and it becomes a single-compartment cylindrical mill, and the grinding body can also be made of steel segments.

　　Raw materials are fed into the hollow cylinder for grinding through the hollow journal, and the cylinder is equipped with various diameters of grinding media (steel balls, steel rods or gravel, etc.). When the cylinder around the horizontal axis to a certain rotational speed, installed in the cylinder media and raw materials in the centrifugal force and friction, with the cylinder to reach a certain height, when its own gravity is greater than the centrifugal force, it will be separated from the cylinder wall ejection drop or roll down, due to the impact of the crushed ore. At the same time in the mill rotation process, grinding media sliding movement between each other on the raw materials also produce grinding effect. The ground material is discharged through the hollow journal.

　　Mechanical structure

　　Ball mill consists of feeding part, discharging part, rotary part, transmission part (reducer, small transmission gear, motor, electric control) and other main parts. The hollow shaft is made of cast steel with removable inner lining, the rotary gear is made of cast hobbing gear, and the cylinder is lined with wear-resistant lining plate, which has good abrasion resistance. The machine runs smoothly and works reliably.

　　The main machine of ball mill includes cylinder, lining made of wear-resistant material in the cylinder, bearing which carries the cylinder and maintains its rotation, and driving part, such as motor, and transmission gears, pulleys, belts and so on.

　　About the parts called blade, generally not the main components, in the feeding end of the components of the feeding port within the spiral can be called its internal spiral blade, in the discharging end of the components of the discharging port within the spiral can also be called its internal spiral blade.

　　In addition, if the auxiliary equipment at the discharge end is used in the screw conveyor, there will be a part called spiral blade in the equipment, but strictly speaking, it is not considered as a part of the ball mill.

　　According to the material and discharge mode, dry ball mill and wet lattice type ball mill can be selected. Energy-saving ball mill, adopting self-aligning double-row centripetal spherical roller bearings, low running resistance and remarkable energy-saving effect. In the cylinder part, a section of conical cylinder is added at the discharge end of the original cylinder, which not only increases the effective volume of the mill, but also makes the distribution of media in the cylinder more reasonable. This product is widely used in non-ferrous metal, ferrous metal, non-metallic ore dressing field and chemical industry, building materials industry for material grinding use.

　　Correct operation steps

　　1, before turning on the equipment, we first need to check the lubrication between the mechanical parts, after making sure that all the preparations have been perfect, first start the ball mill discharge device, ball mill power supply, and finally start the feeding device.

　　2, in the material into the box, first need to check whether the steel plate ball installed in the box body is set up, whether the number is appropriate.

　　3、After the ball mill is turned on, it is necessary to carry out a test run in empty box first, after making sure that the contact surfaces between the box and mechanical parts are sealed and well lubricated, then start the operation.

　　4, and, the start of the ball mill, is to cooperate with other jobs with the staff of the operation of the machine must be seen after the corresponding command signal, can be carried out.

　　5, must be sure to determine the material and the feed port are stopped after the operation, before closing the discharge port.

　　6, usually for the maintenance of the equipment should be timely, reasonable and comprehensive. After the ball mill completely stops running, you need to carefully clean up the grinding media in the box, to extend the service life of machinery and equipment, reduce industrial costs.

　　Selection tips

　　1, to ensure that the mill's production capacity; the selected grinding equipment, to ensure that the required grinding fineness under the conditions, to complete the specified output.

　　2, the production capacity should be higher than the design; design should take into account the changes in the hardness and fineness of the ore, the general deposit of deep ore hardness or fineness, should be able to adapt to the selected mill, while ensuring that the initial smooth production.

　　3, must do grinding test; in the design of no actual information as the basis, must be required to make the grinding test, especially large-scale mineral processing plant, should be obtained from the basic data for the mill selection calculation and proportion of enlargement.

　　4, give due consideration to the large-scale equipment; large-scale equipment is the 21st century since the design tendency. Because of the large-scale equipment, the total equipment weight is light, covers an area of less, fewer production systems, operators and auxiliary systems less, the corresponding investment and production costs are low. However, large-scale equipment operation and management level requires a high level of operation rate, if slightly lower, will greatly reduce the output of mineral processing plant.

　　5, the choice of high operating rate of equipment; in the same type of equipment, there are good and bad old and new points. Rod mill, autogenous mill sometimes operating rate is lower, but under certain conditions is still applicable. In principle, should be selected to run a high rate of equipment, in order to reduce maintenance and parking time.

　　6, understand the hardness of minerals, grade and other properties, try to choose energy-saving ball mill.

　　7, know the fineness required for mineral grinding, according to the fineness of their own mineral requirements, select the aperture of the closed plate and the position of the bin.

　　8、According to the requirement of output, choose the diameter and length of ball mill appropriately.

　　9, choose a new generation of transformation type ball mill, it is best to your mineral corresponding to the professional ball mill manufacturers to buy

　　10, select the ball mill large teeth, small teeth modulus, as well as motor, minus the number of manufacturers, according to the ball mill price, the requirements of the liner material and the thickness of the mill body steel plate.