classification of ball mills

ball mills | air classification | united states

The company manufactures air classifiers, ball mills and stirred media mills for the production of fine, superfine and ultrafine powders for the mineral, mining, cement, lime, metal powder and chemical industries.

RSG Inc, manufactures air classifiers, ball mills and stirred media mills for the production of fine, superfine and ultrafine powders for the mineral, mining, cement, lime, metal powder and chemical industries.

grinding cylpebs

Our automatic production line for the grinding cylpebs is the unique. With stable quality, high production efficiency, high hardness, wear-resistant, the volumetric hardness of the grinding cylpebs is between 60-63HRC,the breakage is less than 0.5%. The organization of the grinding cylpebs is compact, the hardness is constant from the inner to the surface. Now has extensively used in the cement industry, the wear rate is about 30g-60g per Ton cement.

Grinding Cylpebs are made from low-alloy chilled cast iron. The molten metal leaves the furnace at approximately 1500 C and is transferred to a continuous casting machine where the selected size Cylpebs are created; by changing the moulds the full range of cylindrical media can be manufactured via one simple process. The Cylpebs are demoulded while still red hot and placed in a cooling section for several hours to relieve internal stress. Solidification takes place in seconds and is formed from the external surface inward to the centre of the media. It has been claimed that this manufacturing process contributes to the cost effectiveness of the media, by being more efficient and requiring less energy than the conventional forging method.

Because of their cylindrical geometry, Cylpebs have greater surface area and higher bulk density compared with balls of similar mass and size. Cylpebs of equal diameter and length have 14.5% greater surface area than balls of the same mass, and 9% higher bulk density than steel balls, or 12% higher than cast balls. As a result, for a given charge volume, about 25% more grinding media surface area is available for size reduction when charged with Cylpebs, but the mill would also draw more power.

ball mill classification | henan deya machinery co., ltd

Ball mills are also classified by the nature of the discharge. They may be simple trunnion over-flow mills, operated in open or closed circuit, or grate discharge (low-level discharge) mills. The latter type is fitted with discharge grates between the cylindrical mill body and the discharge trunnion. The pulp can flow freely through the openings in the grate and is then lifted up to the level of the discharge trunnion. These mills have a lower pulp level than overflow mills, thus reducing the dwell time of particles in the mill. Very little over grinding takes place and the product contains a large fraction of coarse material, which is returned to the mill by some form of classifying device. Closed-circuit grinding, with high circulating loads, produces a closely sized end product and a high output per unit volume compared with open circuit grinding. Grate discharge mills usually take a coarser feed than overflow mills and are not required to grind so finely, the main reason being that with many small balls forming the charge the grate open area plugs very quickly. The trunnion overflow mill is the simplest to operate and is used for most ball mill applications, especially for fine grinding and regrinding. Energy consumption is said to be about 15% less than that of a grate discharge mill of the same size, although the grinding efficiencies of the two mills are the same.

how many types of ball mill? - jxsc machine

Ball mill is important grinding equipment in the beneficiation plant, used for grinding ores to powders before they are magnetically or chemically processed. How Many Types of Ball Mill? There are many manufacturers producing ball mills on the market, how to choose the right one suits for your production? Here are a quick introduction and classification of ball mills for your reference.

1. Short-cylinder ball mill: The length (L) of the cylinder is less than twice the diameter (D) of the cylinder, that is, the ball mill with L 2D is a short-cylinder ball mill. Single-bin structure ball mill, which is mainly used for coarse grinding or primary grinding, has high efficiency.

2. Rod mills usually equipped with steel rod which diameter mostly between 50-100mm, need a longer grinding time. The number of bins in a rod mill is generally two to four, and there are some differences in the grinding media loaded in each bin. To ensure the final effect of grinding, the staff will place the cylindrical steel rod in the first bin, and the steel ball or steel segment in several other bins.

3. The grinding media in the gravel mill mainly include pebbles, gravel, sandstone, ceramic balls, etc. Gravel mills mostly use porcelain or granite as lining boards, and are widely used in the production fields of cement, ceramics and so on.

1. Overflow type: discharge ore through the hollow shaft. When the ore discharge surface is higher than the slurry surface, the finished product is discharged and the ore is automatically discharged by gravity, thus the overflow ball mill saves energy.

2. Grate discharge ball mill: the ore is discharged through the grate plate. The grating part can strictly control the minerals discharge size that meets the demand, it has a good effect on fine particle grinding.

2. The intermittent ball mill can not continuous operation, at the same specification, its output is lower. The feeding and discharging time is set according to the characteristics of the grinding material. The intermittent ball mill is suitable for the mixing and grinding of materials, lower power consumption. Many ball mill has been transformed into continuous, so users do not have to worry about the production output problem.

1. Central transmission ball mill: The driving power of this type of mill is in the center of the fuselage, and the motor realizes the operation of the ball mill through a reducer. During operation, the hollow shaft in the center of the ball mill drives the grinding body to rotate under the drive of the power system.

1. Wet ball mill: Water is added at the same time as the material is fed, and the material is discharged into a certain concentration of slurry and discharged. In a closed-circuit system, it is composed of a closed-circuit operation with a hydraulic classification device.

2. Dry ball mill: Some discharges are drawn by air current, and the mill and wind classification device form a closed circuit. For example, the cement mill adopts self-flow discharge. The capacity of the dry ball mill is larger, and the energy-saving effect of wet ball mill is better.

1. According to the working conditions and material characteristic Minerals that cannot be touched with water, minerals that are sticky after adding water, and the mining plant in areas where water resources are scarce, are suitable for grinding with a dry ball mill. Under other conditions, it is better to use a wet ball mill which has a better grinding effect, and energy-saving performance. 2. Energy consumption Choose an energy-saving ball mill or ordinary ball mill according to the capacity of electric power supply and energy consumption limitation. 3. Capacity If you require high capacity, choose a continuous ball mill. The vibrating feeder can automatically feed, so the continuous ball mill can keep running for 24 hours. JXSC provides you free selection service, engineers online!

oppsite classification of grinding media - page 1 of 1

Hello, We have got a strange phenomenan in one of our cement ball mill second compartment ... in checking we have observed thatthe grinding media had sorted and classified oppositely inside the second compartment as the following:25 mm (near intermediate diaphragm),30 mm, 40 mmand finaly 50 mm (near mill out let diaphragm).How can grinding media be classified like this? Is there any reason for such phenomenan?? Mill is running now with low capacity andlow blaine and don't know how to deal with it. Regards

We have got a strange phenomenan in one of our cement ball mill second compartment ... in checking we have observed thatthe grinding media had sorted and classified oppositely inside the second compartment as the following:25 mm (near intermediate diaphragm),30 mm, 40 mmand finaly 50 mm (near mill out let diaphragm).How can grinding media be classified like this? Is there any reason for such phenomenan?? Mill is running now with low capacity andlow blaine and don't know how to deal with it.

Hello David, Reverse classification may occur in ball mill. If your grinding media wear rate is high and p.wt of chamber is too low. It is indicate by mill frequently chocking problem. If your mill is going to chocking condition, mill o/l blain low , Main drive KW too much variation ( lower side to normal ) Classifying linears at starting worn out Pl send your operating data on my Mail id [email protected] With regards Gks

classification of ball mill acoustic for predictive grinding using pca | springerlink

The aim of this paper is to design a classification model to predict the terminating condition of a ball mill in raw material specific application. The acoustics of a running ball mill in different phases of grinding is analyzed to derive the signatures of the signal with different raw materials. Here we classify the sound signatures of the mill, which helps us to predict the characteristics of different running conditions with different size distribution of the materials. Using stereophonic microphones acoustic of a running ball mill is captured. The acoustic signal is then fragmented based on one rotation of the mill and saved in an appropriate format for further analysis. The statistical moments of each fragment are taken as the parameters and applied Principal Component Analysis to select the important features. Finally, we classify the analyzed data to find the running state of the mill. The classification model is tuned in order to achieve an experimental result from the simulated result. Also in real time the model has been tested.

stirred mill - an overview | sciencedirect topics

Vertical stirred mills are usually charged with media occupying 80% of the mill volume which is in sharp contrast to tumbling mills that are seldom charged more than 40% of their volumes to allow space for the tumbling action to develop. The stirred mills are charged with a media size of 1012mm and operated at a maximum tip speed of 38m/s. The Metso detritor mill, however, has a maximum tip speed of 1112m/s. Even though a finer ground product is obtained with higher speeds, a limit has to be imposed. This is to allow the separation of media and mineral particles at the top of the mill where a settling zone develops. The ultrafine ground product is usually discharged as it passes through the separating screen. It also takes with it fine media product. The Metso detritor mill uses a screen size of 300m to retain sand when used as a media.

During operation a small amount of heat is generated. This affects the viscosity of the slurry. According to Kwade [7], if the viscosity of the slurry is too high the grinding efficiency is reduced as activity in the grinding chamber is inhibited and the contact between the grinding media and the particles is decreased resulting in less abrasive action on the mineral particles. Thus, the heat generated during media stirring could assist in lowering the slurry viscosity and hence benefit grinding efficiency.

The stress intensity and the number of stress events determine the specific energy to achieve a certain product fineness. The number of stress events is a function of mill operating parameters such as grind time, stirrer speed, percent solids and media size. The relationship between stress intensity and specific energy was shown by Kwade as indicated in Figure10.10.

The stress energy available to particle breakage is distributed in different sections of the mill, being maximum near the tip of the stirrer. For a satisfactory grind and size reduction of all particles, the residence time of the slurry in the mill is the prime factor. Experience so far indicates that about 3060seconds of travel time through a mill is adequate.

It may be noted that all the stress energy generated are not transferred to the mineral particles and the media hardness and media size affects the product size. The portion of the stress energy transferred to the particles depends on the Youngs modulus of both the grinding media and the particles [8].

The Vertimill is a vertical stirred mill that uses a helical screw to impart motion in the charge. Mechanically, the Vertimill is a very simple machine with an agitating screw suspended into the grinding chamber, supported by spherical roller bearings, and driven by a fixed speed motor through a planetary gearbox. Figure 8.14 presents a schematic diagram of the Vertimill. The screw rotates slowly such that the ball charge and slurry are not fluidized, but settle under gravity. The screw action pulls the ball charge up the center of the mill, and the charge eventually cascades over the edge of the screw, creating a general downward flow pattern at the mill perimeter. This pattern of flow, coupled with the low velocities involved, ensures that the grinding media and particles stay in contact with one another, thus enabling the efficient transfer of the drive energy into attrition and abrasion breakage throughout the charge. The operating conditions of the Vertimill are very similar to those of the conventional ball mill in the sense that the percentage solids of the feed should be kept in the range of between 65% and 75% by mass. The power draw of the mill is directly linked to the mass of balls within the mill. The distinct advantage that the VTM has over the conventional ball mill is its ability to use media smaller than 25mm more effectively.

In the past 20 years, more than 60 Vertimill machines have been sold for iron ore applications, with more than 20 of those in the last 2 years alone. Table 8.2 lists examples of the Vertimill in Brazilian iron ore applications. The Metso Vertimill is very common in regrind applications, but the industry quickly realized its potential in coarser applications as well.

where P is the shear power (W), the viscosity of the mill contents (N.s m2) (for which a relationship was given), the angular velocity (rad s1), and V the shear volume (referring to all the shear surface pairs between an impeller and the mill chamber). With appropriate calibration the predicted power matched the measured power for the data of Gao et al. (1996) and Jankovic (1998).

The IsaMill milling technology is a large-scale commercial high-speed stirred mill that is currently under development for coal micronising applications. The technology achieves very high energy efficiencies by using small milling balls in a high intensity configuration (>300 kWmm3). It is claimed that the technology (Fig.15.7) can produce coal with 90% of the particles less than 20m.

IsaMill technology is receiving serious consideration as part of a CSIRO investigation into preparing micronised coal for coal/water fuel in a diesel engine to deliver base-load power (see Section15.10.1).

Vibratory mills use oscillatory motion of the mill shell to agitate the media. As for the stirred mills, the active grinding zone encompasses the entire mill volume. The grinding energy is supplied by the inertia of the media and is not limited by gravity. In principle, high energy can be supplied to quite fine media, making these devices attractive for ultrafine grinding applications. By very careful matching of media size, powder size, and energy input (based on vibrational amplitude and frequency) it should be possible to achieve quite high grinding efficiencies. Unfortunately, mechanical design for reliability and low maintenance is not simple. Problems in these areas have tended to limit their large-scale application.

Different kind of mills are suitable for grinding, mechanical alloying and mechanical milling such as horizontal mills (tumbler ball mill), stirred mill (attritor, e.g. Szegvari attrition mill1), planetary ball mill, vibrating mill (tube vibrating mill, Sweco vibrating mill and shaker vibrating mill (e.g. Spex is a lab-scale mill3)). Their working principles and operating conditions are summarised in Fig. 12.1 and Table 12.1. The classification on a scale of increasing mill energy is: horizontal ball mill, attritor, planetary ball mill and vibrating ball mill. For example, a process that takes only a few minutes in the SPEX mill can take hours in an attritor and a few days in a commercial tumbler ball mill.

The choice of a milling technique is determined by many parameters. For example, attrition mills are more efficient than tumbler ball mills for mixing and blending WC-Co cutting tool powders because of short milling time, production of fine particle size (submicron sized) and enhanced smearing of Co onto carbide particles. However, as the product output is relatively low with attrition mills, tumbler ball mills are usually used for production runs of over 100kg/day. Moreover, powder contamination, which is an important criterion for many applications, can be due to the initial purity of the powder, the milling equipment (design), the milling operating conditions (mill speed, balls size and material, atmosphere) and/or the use of process control agent. It increases with milling time, milling intensity and with the reduction of the difference of strength/hardness between the powder and the milling balls.

There are in general two methods by which nanoparticles can be produced using high-energy milling: (i) milling alone and (ii) combining chemistry and milling (referred to as chemical-mechanical milling or mechanochemical processing). It is suggested that these methods offer the advantage of being easily scaled. References [19 and 20] are good starting points for further reading.

High-energy milling processes involve the comminution of bulk materials. The principle of comminution is centred on applying physical forces to bulk material so as to effect breakage into smaller sizes. The forces required to effect breakage are usually a combination of either impact or shear. Material is introduced into a milling chamber in which grinding (milling) media are contained. Milling occurs when the media is made to move either by stirring (using a rotor) or by shaking/vibrating the chamber and contacts the bulk material thus imparting, depending on the milling parameters, either impact or shear forces on it. Breakage can occur through a variety of mechanisms and are generally described as attrition, abrasion, fragmentation or chipping and occur both at the macro and microscopic level [21]. This is illustrated in Figs 1.3 and 1.4

The rate at which comminution occurs is dependent on the size and frequency with which forces are applied. Breakage is influenced by both extrinsic and intrinsic factors. Intrinsic factors include such things as material properties (hardness, density, size) whilst extrinsic factors are determined by the amount of energy put into the system and the efficiency with which that energy is translated to the milling process. The latter is determined by variables such as vibrating frequency (in a rotorless mill), rotor speed (in a stirred mill), mill design, media size and loading, solids loading and whether the milling is performed dry or wet. These variables dictate which force regime predominates (i.e. shear or impact) which in turn dictate milling rate and efficiency. In high-speed stirred mills the effect of mill tip speed, media size and density can be evaluated simultaneously using the grinding media 'stress intensity' approach and an illustration of this is summarised in Fig. 1.5 which shows a plot of product particles size (starting size 45 m, product size 26 m) versus stress intensity for a pin mill using a zinc concentrate.

A variety of mills are commercially available and range from tumbling, shaker, vibratory, planetary and stirred ball mills. Production of nanoparticles using this technique is sometimes limited by the need for extended milling times, material properties and contamination issues. Attrition methods allow the production of alloys and composites that cannot be synthesised by conventional casting methods. They have also gained attention as non-equilibrium processes resulting in solid state alloying beyond the equilibrium solubility limit and the formation.

The types of nanoparticles produced by the attrition milling technique are generally alloys or single-phase powders. When a single-phase elemental powder (or intermetallic) is milled, grain size asymptotically reduces to a range of 330 nm [19]. For alloys produced by this method, unstable intermediate substances are formed, from mixing and diffusion as a consequence of repeated deformation and folding of the different metals. These intermediates allow the chemical reactions necessary for alloy formation to occur [11].

For non-metallic compounds (carbides, oxides, etc.) the reduction in grain size is consequent on fracturing and cold welding and the limit to minimum grain size is determined by the minimum size that does not support nucleation and propagation of cracks within the grain. For metallics, on the other hand, it is thought that the reduction in grain size is a process where localised plastic deformation is induced, subgrains are formed (by eradication of dislocations) which combine (through intimate mechanical contact) to form discrete grains. The latter process is analogous to recrystallisation observed during hot forming of metals and alloys but in these circumstances at low temperatures. In intermetallics, the process is thought to be different again in that grain formation is due to nucleation (on a nanoscale) followed by a limited growth of the generated phase [20,23]. There are numerous examples in the literature of alloy and mixed metal oxide production using this technique [20,28]. Few examples can be found where single-phase powders or particles are produced at the nanoscale level [24,25].

In this technique, a large number of small grinding media are agitated by impellers, screws, or disks in a chamber. Breakage occurs mainly by the collision of the media. There are designs of the mill with a vertical or horizontal rotating shaft with wet or dry systems (Fig. 2.19).

The medium agitating mill is one of the most efficient devices for micronizing materials and has been in regular use for the production of fine particles and mechanical alloying processes. A typical stirred mill with a vertical rotating shaft and horizontal arms is shown in Fig. 2.20. This stirring action causes a differential movement between balls and the material being milled, thus a substantially higher degree of surface contact than is achieved in tumbling or vibratory mills is ensured. Milling takes place by impact and shear forces. The rotating charge of balls and milling product form a whirl where the milling product is impacted by balls moving in various trajectories.

The attrition mill agitator rotates at speeds ranging from 60rpm for production units to 300rpm for laboratory units and uses media that range from 3 to 6mm while ball mills use large grinding media, usually 12mm or larger, and run at low rotational speeds of 1050rpm. Power input to attrition mills is used to agitate the medium, not to rotate or vibrate heavy drums. Therefore, specific energy consumption of attrition mills is significantly less than with ball mills. Table 2.4 offers a comparison of grinding mills by rotational velocity. In the attrition grinding process, grinding time is related to medium diameter and agitator speeds [12], within given limits, as:

where t is grinding time required to reach a certain medium particle size; k is a constant that varies with the suspension being processed and the type of medium and mill being used; d is the diameter of the grinding medium; and n is shaft movement, in rpm.

Attrittion mills are classified as batch-, continuous-, or circulation-type mills. In the batch mill, material is loaded into the chamber and ground until the desired dispersion and particle size are achieved. Chamber walls are jacketed so that either hot or cold water can be circulated to control and maintain the temperature of the charging. The batch attrition mills can process high-density material, such as tungsten carbide, as well as viscous materials. They are also suitable for dry grinding and for producing dispersion-strengthened metals by means of mechanical alloying.

Continuous attrition mills, more appropriate for large production output, consist of a tall, jacketed chamber through which previously prepared slurry is pumped in at the bottom and discharged at the top. Grids located at the bottom and top retain the grinding medium, as shown in Fig. 2.21.

The circulation grinding system comprises an attrition mill and a large holding tank, generally 10 times the volume of the grinding unit. The attrition mill contains grids that restrain the medium while the slurry passes through. Usually, the contents of the holding tank are passed through the system at a rate of 10 times per hour. The slurry can be monitored continuously and processing is stopped when the desired particle size dispersion is achieved.

Dry milling can provide reduced transportation costs compared to wet grinding because 50% of the gross weight is liquid in many wet slurry processes. Because the removal of the liquid from a wet grinding process involves not only another process step but also requires large amounts of energy, dry grinding can provide reduced energy costs. Another advantage is the elimination of waste liquid disposal.

Attrition mills find application for hard materials such as carbides and hard metals where conventional tumbling and vibratory ball mills are less efficient. The principal advantages of attrition mills for mixing and blending tungsten carbide with cobalt as binder metal cutting tool powders include a short milling time, the production of fine particle size (submicron sizes), and the enhanced coating of cobalt onto the surface of tungsten carbide particles [25]. Attrition mills effectively grind metals in inert atmospheres, such as in solid state or mechanical alloying.

Previous work (Heitzmann [8]) performed with coloured tracer experiments in a glass body version of a four blades Dyno mill showed that the action of the stirrer - beads system was first to delimit four perfectly mixed cells centered on each of the four blades. Further, it has been shown that classical models (plug flow, cascade of perfectly mixed cells, dispersion models) were unable to correctly represent RTD experiments. An internal recirculation loop model, with a single adjustable parameter R (see Figure 1), was considered and gave very good results in continuous milling of suspensions of known grinding kinetics (Berthiaux et al. [9]).

Another important conclusion of this work was concerned with the physical meaning of the recirculation ratio R which is undoubtedly linked with the local hydrodynamic conditions, such as porosity, stirrer speed of rotation N, and perhaps mill flow-rate Q. It was also suggested that there exists an optimum value of R that leads to the best continuous grinding conditions (see Figure 2). For example, low values of R benefits the flow itself as it approaches plug flow through tanks in series, while it clearly slows down the kinetics of grinding because the bead - particle collisions are of a lower intensity. In the absence of kinetic data, typical R-values should then range between 0.5 and 5.

The procedure followed to obtain these RTD curves becomes tedious when dealing with a greater number of perfectly mixed cells, or better said a greater number of stirring blades, as it is the case for other types of mills. In general, the analytical or numerical derivation of the RTD from any complex model is in fact highly subjected to errors when done by the classical transfer function method. Particularly, many problems can be incurred when hypotheses are made to simplify the mathematical equations, which may lead to unrealistic dynamic behaviour (see Gibilaro et al. [10]). The advantage of using the Markov chain approach lies in the fact that it is systematic, and its application does not depend on the complexity of the flow scheme.

A Markov chain is a system which can occupy various states, and whose evolution is defined once an initial state and the probability transitions between the states are fixed. It can therefore be said that a Markov chain does not have memory. In the case of flow problems (Fan et al. [11]), the system is a fluid element, the states are the perfectly mixed cells of the flow model (as plug flow can be represented by a series of such cells), and the probability transitions are fixed by elementary mass balances.

For example (Figure 3), the probability pii of remaining in cell i is exp(t/i), where t is the time interval under which the system is observed, and i is the geometric residence time corresponding to cell i. The other transitions pij depend then on the flow rate ratios and on the value of 1- exp(t/j), which is the probability of getting out of cell i during t. All these information are then collected in a probability transitions matrix P, whose rows (i) and columns (j) are the pijs. Further, the initial state of the system is represented by a single row E0, being En the state of system after n transitions (steps of duration t), which is available from the following matrix product (Eq.1):

The last element of En, which is the collecting cell or outlet of the network, represents therefore the dynamic response of the system to a perturbation that may be a tracer impulse: E0=[1 0 0]. Simulation of the RTD curve of the model is further performed by letting t become smaller and smaller until the stability of the solution is ensured.

vertical ball mill can grind coarse and hard granular materials evenly

The vertical ball mill integrates the dispersion and grinding of materials, and the grinding medium has a strong impact force in the barrel. It is suitable for materials with high viscosity and difficult to grind, such as high-hardness carbon black.

The vertical ball mill has stable performance, supports dry and wet grinding, and has unique performance for coarse and thickened materials. Vertical ball mill can be widely used for dispersion and grinding of solid or powder materials in paint, medicine, building materials, chemical industry and other industries.

The barrel of the vertical ball mill is a welded structure, and a protective lining is attached to the inner wall. There is an opening on the cylinder body to facilitate the maintenance of the mixing shaft and the replacement of mixing medium. There are spiral blades on the stirring shaft of the vertical ball mill, and the stirring structure is made of wear-resistant materials.

The media in the barrel of the vertical ball mill includes grinding media and crushed material transport media. The grinding medium is generally wear-resistant steel balls. The ball diameter is smaller than that ofhorizontal ball mill. Glass balls or ceramic balls (such as verticalceramic ball mill) can also be used according to the grinding requirements. For the case where the finished product has special purity, the grinding medium can also be the raw material with a larger size (such as SAG mill).

The crushed material transport media of vertical ball mills is divided into dry and wet types, so vertical ball mill also have dry vertical ball mill and wet vertical ball mill. The transport media in the dry-type vertical mill is generally air, and the protective gas can be used for the easily oxidized materials. Wet vertical mill generally use water as the transport medium, and can also be replaced with oil or other liquids.

The stirring shaft of the vertical ball mill drives the steel balls to turn in a vortex shape, and the materials are ground and crushed by the squeezing force generated by the movement of the steel balls, so as to achieve the grinding effect.

As a ball mills supplier with 22 years of experience in the grinding industry, we can provide customers with types of ball mill, vertical mill, rod mill and AG/SAG mill for grinding in a variety of industries and materials.

wet grid ball mill

Grid ball mill is widely used in smashing all kinds of ores and other materials, ore dressing and national economic departments like building and chemical industries etc. The size of ore shall not exceed 65mm and the best feed size is under 6mm. The effect in this job is better than coarse grinding. Grid ball mill consists of the shell, feeding part, discharging part, main bearing, lubricating system, driving system and other parts. There is wearing a liner inside the shell, and both ends of the shell are provided with a flange. The end cover of the mill is connected with the flange plate. The feeding part consists of the head, trunnion and feeding device. The discharge part includes the grid plate, head, and discharge trunnion.

Wet Grid ball mill is mainly used for mixing and grinding materials in two types: dry grinding and wet grinding .It has advantages of fineness uniformity and power saving. The machine uses different types of liner to meet different customer needs. The grinding fineness of material can be controlled by grinding time. The electro-hydraulic machine is auto-coupled and decompressed to reduce the starting current, and its structure is divided into integral type and independent type.

Compared with similar products,Wet Grid ball mill has the characteristics of low investment, low energy consumption, novel structure, simple operation, stable and reliable performance. It is suitable for mixing and grinding ordinary and special materials. The users can choose the right type, liner and medium type by considering the specific gravity, hardness, yield and other factors. The grinding medium is Wet Grid ball.

1.The ball mill is composed of a horizontal cylinder, a hollow shaft for feeding and discharging, and a grinding head. The main body is a long cylinder made of steel. The cylinder is provided with an abrasive body, and the steel lining plate is fixed to the cylinder body. The grinding body is generally a steel ball and is loaded into the cylinder according to different diameters and a certain proportion, and the grinding body can also be used with a steel section.

2.According to the particle size of the grinding material, the material is loaded into the cylinder by the hollow shaft of the wet grid ball mill feeding end. When the ball mill cylinder rotates, the grinding body acts on the cylinder liner due to the action of inertia and centrifugal force and friction. It is carried away by the cylinder. When it is brought to a certain height, it is thrown off due to its own gravity. The falling abrasive body crushes the material in the cylinder like a projectile.

3.The material is uniformly fed into the first chamber of the mill by the feeding device through the hollow shaft of the feeding material. The chamber has a step liner or a corrugated liner, and various steel balls are loaded therein. The rotation of the cylinder generates centrifugal force to bring the steel ball to a certain extent. The height drops and then hits and grinds the material. After the material reaches the rough grinding in the first bin, it enters the second bin through the single-layer partition plate. The bin is embedded with a flat liner with steel balls inside to further grind the material. The powder is discharged through the discharge raft to complete the grinding operation.

The main function of the steel ball in the ball mill is to impact crush the material and also play a certain grinding effect. Therefore, the purpose of grading steel balls is to meet the requirements of these two aspects. The quality of the crushing effect directly affects the grinding efficiency, and ultimately affects the output of the ball mill. Whether the crushing requirement can be achieved depends on whether the grading of the steel ball is reasonable, mainly including the size of the steel ball, the number of ball diameters, and the ball of various specifications. Proportion and so on.

The ball mill is composed of the main part such as a feeding part, a discharging part, a turning part, a transmission part (a reduction gear, a small transmission gear, a motor, and electric control). The hollow shaft is made of cast steel, the inner lining can be replaced, the rotary large gear is processed by casting hobbing, and the barrel is embedded with wear-resistant lining, which has good wear resistance. The machine runs smoothly and works reliably.