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A ball mill is a type of grinder used to grind and blend bulk material into QDs/nanosize using different sized balls. The working principle is simple; impact and attrition size reduction take place as the ball drops from near the top of a rotating hollow cylindrical shell. The nanostructure size can be varied by varying the number and size of balls, the material used for the balls, the material used for the surface of the cylinder, the rotation speed, and the choice of material to be milled. Ball mills are commonly used for crushing and grinding the materials into an extremely fine form. The ball mill contains a hollow cylindrical shell that rotates about its axis. This cylinder is filled with balls that are made of stainless steel or rubber to the material contained in it. Ball mills are classified as attritor, horizontal, planetary, high energy, or shaker.
Grinding elements in ball mills travel at different velocities. Therefore, collision force, direction and kinetic energy between two or more elements vary greatly within the ball charge. Frictional wear or rubbing forces act on the particles, as well as collision energy. These forces are derived from the rotational motion of the balls and movement of particles within the mill and contact zones of colliding balls.
By rotation of the mill body, due to friction between mill wall and balls, the latter rise in the direction of rotation till a helix angle does not exceed the angle of repose, whereupon, the balls roll down. Increasing of rotation rate leads to growth of the centrifugal force and the helix angle increases, correspondingly, till the component of weight strength of balls become larger than the centrifugal force. From this moment the balls are beginning to fall down, describing during falling certain parabolic curves (Figure 2.7). With the further increase of rotation rate, the centrifugal force may become so large that balls will turn together with the mill body without falling down. The critical speed n (rpm) when the balls are attached to the wall due to centrifugation:
where Dm is the mill diameter in meters. The optimum rotational speed is usually set at 6580% of the critical speed. These data are approximate and may not be valid for metal particles that tend to agglomerate by welding.
The degree of filling the mill with balls also influences productivity of the mill and milling efficiency. With excessive filling, the rising balls collide with falling ones. Generally, filling the mill by balls must not exceed 3035% of its volume.
The mill productivity also depends on many other factors: physical-chemical properties of feed material, filling of the mill by balls and their sizes, armor surface shape, speed of rotation, milling fineness and timely moving off of ground product.
where b.ap is the apparent density of the balls; l is the degree of filling of the mill by balls; n is revolutions per minute; 1, and 2 are coefficients of efficiency of electric engine and drive, respectively.
A feature of ball mills is their high specific energy consumption; a mill filled with balls, working idle, consumes approximately as much energy as at full-scale capacity, i.e. during grinding of material. Therefore, it is most disadvantageous to use a ball mill at less than full capacity.
Grinding elements in ball mills travel at different velocities. Therefore, collision force, direction, and kinetic energy between two or more elements vary greatly within the ball charge. Frictional wear or rubbing forces act on the particles as well as collision energy. These forces are derived from the rotational motion of the balls and the movement of particles within the mill and contact zones of colliding balls.
By the rotation of the mill body, due to friction between the mill wall and balls, the latter rise in the direction of rotation until a helix angle does not exceed the angle of repose, whereupon the balls roll down. Increasing the rotation rate leads to the growth of the centrifugal force and the helix angle increases, correspondingly, until the component of the weight strength of balls becomes larger than the centrifugal force. From this moment, the balls are beginning to fall down, describing certain parabolic curves during the fall (Fig. 2.10).
With the further increase of rotation rate, the centrifugal force may become so large that balls will turn together with the mill body without falling down. The critical speed n (rpm) when the balls remain attached to the wall with the aid of centrifugal force is:
where Dm is the mill diameter in meters. The optimum rotational speed is usually set at 65%80% of the critical speed. These data are approximate and may not be valid for metal particles that tend to agglomerate by welding.
where db.max is the maximum size of the feed (mm), is the compression strength (MPa), E is the modulus of elasticity (MPa), b is the density of material of balls (kg/m3), and D is the inner diameter of the mill body (m).
The degree of filling the mill with balls also influences the productivity of the mill and milling efficiency. With excessive filling, the rising balls collide with falling ones. Generally, filling the mill by balls must not exceed 30%35% of its volume.
The productivity of ball mills depends on the drum diameter and the relation of drum diameter and length. The optimum ratio between length L and diameter D, L:D, is usually accepted in the range 1.561.64. The mill productivity also depends on many other factors, including the physical-chemical properties of the feed material, the filling of the mill by balls and their sizes, the armor surface shape, the speed of rotation, the milling fineness, and the timely moving off of the ground product.
where D is the drum diameter, L is the drum length, b.ap is the apparent density of the balls, is the degree of filling of the mill by balls, n is the revolutions per minute, and 1, and 2 are coefficients of efficiency of electric engine and drive, respectively.
A feature of ball mills is their high specific energy consumption. A mill filled with balls, working idle, consumes approximately as much energy as at full-scale capacity, that is, during the grinding of material. Therefore, it is most disadvantageous to use a ball mill at less than full capacity.
Milling time in tumbler mills is longer to accomplish the same level of blending achieved in the attrition or vibratory mill, but the overall productivity is substantially greater. Tumbler mills usually are used to pulverize or flake metals, using a grinding aid or lubricant to prevent cold welding agglomeration and to minimize oxidation .
Cylindrical Ball Mills differ usually in steel drum design (Fig. 2.11), which is lined inside by armor slabs that have dissimilar sizes and form a rough inside surface. Due to such juts, the impact force of falling balls is strengthened. The initial material is fed into the mill by a screw feeder located in a hollow trunnion; the ground product is discharged through the opposite hollow trunnion.
Cylindrical screen ball mills have a drum with spiral curved plates with longitudinal slits between them. The ground product passes into these slits and then through a cylindrical sieve and is discharged via the unloading funnel of the mill body.
Conical Ball Mills differ in mill body construction, which is composed of two cones and a short cylindrical part located between them (Fig. 2.12). Such a ball mill body is expedient because efficiency is appreciably increased. Peripheral velocity along the conical drum scales down in the direction from the cylindrical part to the discharge outlet; the helix angle of balls is decreased and, consequently, so is their kinetic energy. The size of the disintegrated particles also decreases as the discharge outlet is approached and the energy used decreases. In a conical mill, most big balls take up a position in the deeper, cylindrical part of the body; thus, the size of the balls scales down in the direction of the discharge outlet.
For emptying, the conical mill is installed with a slope from bearing to one. In wet grinding, emptying is realized by the decantation principle, that is, by means of unloading through one of two trunnions.
With dry grinding, these mills often work in a closed cycle. A scheme of the conical ball mill supplied with an air separator is shown in Fig. 2.13. Air is fed to the mill by means of a fan. Carried off by air currents, the product arrives at the air separator, from which the coarse particles are returned by gravity via a tube into the mill. The finished product is trapped in a cyclone while the air is returned in the fan.
The ball mill is a tumbling mill that uses steel balls as the grinding media. The length of the cylindrical shell is usually 11.5 times the shell diameter (Figure 8.11). The feed can be dry, with less than 3% moisture to minimize ball coating, or slurry containing 2040% water by weight. Ball mills are employed in either primary or secondary grinding applications. In primary applications, they receive their feed from crushers, and in secondary applications, they receive their feed from rod mills, AG mills, or SAG mills.
Ball mills are filled up to 40% with steel balls (with 3080mm diameter), which effectively grind the ore. The material that is to be ground fills the voids between the balls. The tumbling balls capture the particles in ball/ball or ball/liner events and load them to the point of fracture.
When hard pebbles rather than steel balls are used for the grinding media, the mills are known as pebble mills. As mentioned earlier, pebble mills are widely used in the North American taconite iron ore operations. Since the weight of pebbles per unit volume is 3555% of that of steel balls, and as the power input is directly proportional to the volume weight of the grinding medium, the power input and capacity of pebble mills are correspondingly lower. Thus, in a given grinding circuit, for a certain feed rate, a pebble mill would be much larger than a ball mill, with correspondingly a higher capital cost. However, the increase in capital cost is justified economically by a reduction in operating cost attributed to the elimination of steel grinding media.
In general, ball mills can be operated either wet or dry and are capable of producing products in the order of 100m. This represents reduction ratios of as great as 100. Very large tonnages can be ground with these ball mills because they are very effective material handling devices. Ball mills are rated by power rather than capacity. Today, the largest ball mill in operation is 8.53m diameter and 13.41m long with a corresponding motor power of 22MW (Toromocho, private communications).
Modern ball mills consist of two chambers separated by a diaphragm. In the first chamber the steel-alloy balls (also described as charge balls or media) are about 90mm diameter. The mill liners are designed to lift the media as the mill rotates, so the comminution process in the first chamber is dominated by crushing. In the second chamber the ball diameters are of smaller diameter, between 60 and 15mm. In this chamber the lining is typically a classifying lining which sorts the media so that ball size reduces towards the discharge end of the mill. Here, comminution takes place in the rolling point-contact zone between each charge ball. An example of a two chamber ball mill is illustrated in Fig. 2.22.15
Much of the energy consumed by a ball mill generates heat. Water is injected into the second chamber of the mill to provide evaporative cooling. Air flow through the mill is one medium for cement transport but also removes water vapour and makes some contribution to cooling.
Grinding is an energy intensive process and grinding more finely than necessary wastes energy. Cement consists of clinker, gypsum and other components mostly more easily ground than clinker. To minimise over-grinding modern ball mills are fitted with dynamic separators (otherwise described as classifiers or more simply as separators). The working principle is that cement is removed from the mill before over-grinding has taken place. The cement is then separated into a fine fraction, which meets finished product requirements, and a coarse fraction which is returned to mill inlet. Recirculation factor, that is, the ratio of mill throughput to fresh feed is up to three. Beyond this, efficiency gains are minimal.
For more than 50years vertical mills have been the mill of choice for grinding raw materials into raw meal. More recently they have become widely used for cement production. They have lower specific energy consumption than ball mills and the separator, as in raw mills, is integral with the mill body.
In the Loesche mill, Fig. 2.23,16 two pairs of rollers are used. In each pair the first, smaller diameter, roller stabilises the bed prior to grinding which takes place under the larger roller. Manufacturers use different technologies for bed stabilisation.
Comminution in ball mills and vertical mills differs fundamentally. In a ball mill, size reduction takes place by impact and attrition. In a vertical mill the bed of material is subject to such a high pressure that individual particles within the bed are fractured, even though the particles are very much smaller than the bed thickness.
Early issues with vertical mills, such as narrower PSD and modified cement hydration characteristics compared with ball mills, have been resolved. One modification has been to install a hot gas generator so the gas temperature is high enough to partially dehydrate the gypsum.
For many decades the two-compartment ball mill in closed circuit with a high-efficiency separator has been the mill of choice. In the last decade vertical mills have taken an increasing share of the cement milling market, not least because the specific power consumption of vertical mills is about 30% less than that of ball mills and for finely ground cement less still. The vertical mill has a proven track record in grinding blastfurnace slag, where it has the additional advantage of being a much more effective drier of wet feedstock than a ball mill.
The vertical mill is more complex but its installation is more compact. The relative installed capital costs tend to be site specific. Historically the installed cost has tended to be slightly higher for the vertical mill.
Special graph paper is used with lglg(1/R(x)) on the abscissa and lg(x) on the ordinate axes. The higher the value of n, the narrower the particle size distribution. The position parameter is the particle size with the highest mass density distribution, the peak of the mass density distribution curve.
Vertical mills tend to produce cement with a higher value of n. Values of n normally lie between 0.8 and 1.2, dependent particularly on cement fineness. The position parameter is, of course, lower for more finely ground cements.
Separator efficiency is defined as specific power consumption reduction of the mill open-to-closed-circuit with the actual separator, compared with specific power consumption reduction of the mill open-to-closed-circuit with an ideal separator.
As shown in Fig. 2.24, circulating factor is defined as mill mass flow, that is, fresh feed plus separator returns. The maximum power reduction arising from use of an ideal separator increases non-linearly with circulation factor and is dependent on Rf, normally based on residues in the interval 3245m. The value of the comminution index, W, is also a function of Rf. The finer the cement, the lower Rf and the greater the maximum power reduction. At C = 2 most of maximum power reduction is achieved, but beyond C = 3 there is very little further reduction.
Separator particle separation performance is assessed using the Tromp curve, a graph of percentage separator feed to rejects against particle size range. An example is shown in Fig. 2.25. Data required is the PSD of separator feed material and of rejects and finished product streams. The bypass and slope provide a measure of separator performance.
The particle size is plotted on a logarithmic scale on the ordinate axis. The percentage is plotted on the abscissa either on a linear (as shown here) or on a Gaussian scale. The advantage of using the Gaussian scale is that the two parts of the graph can be approximated by two straight lines.
The measurement of PSD of a sample of cement is carried out using laser-based methodologies. It requires a skilled operator to achieve consistent results. Agglomeration will vary dependent on whether grinding aid is used. Different laser analysis methods may not give the same results, so for comparative purposes the same method must be used.
The ball mill is a cylindrical drum (or cylindrical conical) turning around its horizontal axis. It is partially filled with grinding bodies: cast iron or steel balls, or even flint (silica) or porcelain bearings. Spaces between balls or bearings are occupied by the load to be milled.
Following drum rotation, balls or bearings rise by rolling along the cylindrical wall and descending again in a cascade or cataract from a certain height. The output is then milled between two grinding bodies.
Ball mills could operate dry or even process a water suspension (almost always for ores). Dry, it is fed through a chute or a screw through the units opening. In a wet path, a system of scoops that turn with the mill is used and it plunges into a stationary tank.
Mechanochemical synthesis involves high-energy milling techniques and is generally carried out under controlled atmospheres. Nanocomposite powders of oxide, nonoxide, and mixed oxide/nonoxide materials can be prepared using this method. The major drawbacks of this synthesis method are: (1) discrete nanoparticles in the finest size range cannot be prepared; and (2) contamination of the product by the milling media.
More or less any ceramic composite powder can be synthesized by mechanical mixing of the constituent phases. The main factors that determine the properties of the resultant nanocomposite products are the type of raw materials, purity, the particle size, size distribution, and degree of agglomeration. Maintaining purity of the powders is essential for avoiding the formation of a secondary phase during sintering. Wet ball or attrition milling techniques can be used for the synthesis of homogeneous powder mixture. Al2O3/SiC composites are widely prepared by this conventional powder mixing route by using ball milling . However, the disadvantage in the milling step is that it may induce certain pollution derived from the milling media.
In this mechanical method of production of nanomaterials, which works on the principle of impact, the size reduction is achieved through the impact caused when the balls drop from the top of the chamber containing the source material.
A ball mill consists of a hollow cylindrical chamber (Fig. 6.2) which rotates about a horizontal axis, and the chamber is partially filled with small balls made of steel, tungsten carbide, zirconia, agate, alumina, or silicon nitride having diameter generally 10mm. The inner surface area of the chamber is lined with an abrasion-resistant material like manganese, steel, or rubber. The magnet, placed outside the chamber, provides the pulling force to the grinding material, and by changing the magnetic force, the milling energy can be varied as desired. The ball milling process is carried out for approximately 100150h to obtain uniform-sized fine powder. In high-energy ball milling, vacuum or a specific gaseous atmosphere is maintained inside the chamber. High-energy mills are classified into attrition ball mills, planetary ball mills, vibrating ball mills, and low-energy tumbling mills. In high-energy ball milling, formation of ceramic nano-reinforcement by in situ reaction is possible.
It is an inexpensive and easy process which enables industrial scale productivity. As grinding is done in a closed chamber, dust, or contamination from the surroundings is avoided. This technique can be used to prepare dry as well as wet nanopowders. Composition of the grinding material can be varied as desired. Even though this method has several advantages, there are some disadvantages. The major disadvantage is that the shape of the produced nanoparticles is not regular. Moreover, energy consumption is relatively high, which reduces the production efficiency. This technique is suitable for the fabrication of several nanocomposites, which include Co- and Cu-based nanomaterials, Ni-NiO nanocomposites, and nanocomposites of Ti,C .
Planetary ball mill was used to synthesize iron nanoparticles. The synthesized nanoparticles were subjected to the characterization studies by X-ray diffraction (XRD), and scanning electron microscopy (SEM) techniques using a SIEMENS-D5000 diffractometer and Hitachi S-4800. For the synthesis of iron nanoparticles, commercial iron powder having particles size of 10m was used. The iron powder was subjected to planetary ball milling for various period of time. The optimum time period for the synthesis of nanoparticles was observed to be 10h because after that time period, chances of contamination inclined and the particles size became almost constant so the powder was ball milled for 10h to synthesize nanoparticles . Fig. 12 shows the SEM image of the iron nanoparticles.
The vibratory ball mill is another kind of high-energy ball mill that is used mainly for preparing amorphous alloys. The vials capacities in the vibratory mills are smaller (about 10 ml in volume) compared to the previous types of mills. In this mill, the charge of the powder and milling tools are agitated in three perpendicular directions (Fig. 1.6) at very high speed, as high as 1200 rpm.
Another type of the vibratory ball mill, which is used at the van der Waals-Zeeman Laboratory, consists of a stainless steel vial with a hardened steel bottom, and a single hardened steel ball of 6 cm in diameter (Fig. 1.7).
The mill is evacuated during milling to a pressure of 106 Torr, in order to avoid reactions with a gas atmosphere. Subsequently, this mill is suitable for mechanical alloying of some special systems that are highly reactive with the surrounding atmosphere, such as rare earth elements.
In spite of the traditional approaches used for gas-solid reaction at relatively high temperature, Calka etal. and El-Eskandarany etal. proposed a solid-state approach, the so-called reactive ball milling (RBM), used for preparations different families of meal nitrides and hydrides at ambient temperature. This mechanically induced gas-solid reaction can be successfully achieved, using either high- or low-energy ball-milling methods, as shown in Fig.9.5. However, high-energy ball mill is an efficient process for synthesizing nanocrystalline MgH2 powders using RBM technique, it may be difficult to scale up for matching the mass production required by industrial sector. Therefore, from a practical point of view, high-capacity low-energy milling, which can be easily scaled-up to produce large amount of MgH2 fine powders, may be more suitable for industrial mass production.
In both approaches but with different scale of time and milling efficiency, the starting Mg metal powders milled under hydrogen gas atmosphere are practicing to dramatic lattice imperfections such as twinning and dislocations. These defects are caused by plastics deformation coupled with shear and impact forces generated by the ball-milling media. The powders are, therefore, disintegrated into smaller particles with large surface area, where very clean or fresh oxygen-free active surfaces of the powders are created. Moreover, these defects, which are intensively located at the grain boundaries, lead to separate micro-scaled Mg grains into finer grains capable to getter hydrogen by the first atomically clean surfaces to form MgH2 nanopowders.
Fig.9.5 illustrates common lab scale procedure for preparing MgH2 powders, starting from pure Mg powders, using RBM via (1) high-energy and (2) low-energy ball milling. The starting material can be Mg-rods, in which they are processed via sever plastic deformation, using for example cold-rolling approach, as illustrated in Fig.9.5. The heavily deformed Mg-rods obtained after certain cold rolling passes can be snipped into small chips and then ball-milled under hydrogen gas to produce MgH2 powders.
Planetary ball mills are the most popular mills used in scientific research for synthesizing MgH2 nanopowders. In this type of mill, the ball-milling media have considerably high energy, because milling stock and balls come off the inner wall of the vial and the effective centrifugal force reaches up to 20 times gravitational acceleration. The centrifugal forces caused by the rotation of the supporting disc and autonomous turning of the vial act on the milling charge (balls and powders). Since the turning directions of the supporting disc and the vial are opposite, the centrifugal forces alternately are synchronized and opposite. Therefore, the milling media and the charged powders alternatively roll on the inner wall of the vial, and are lifted and thrown off across the bowl at high speed.
In the typical experimental procedure, a certain amount of the Mg (usually in the range between 3 and 10g based on the vials volume) is balanced inside an inert gas atmosphere (argon or helium) in a glove box and sealed together with certain number of balls (e.g., 2050 hardened steel balls) into a hardened steel vial (Fig.9.5A and B), using, for example, a gas-temperature-monitoring system (GST). With the GST system, it becomes possible to monitor the progress of the gas-solid reaction taking place during the RBM process, as shown in Fig.9.5C and D. The temperature and pressure changes in the system during milling can be also used to realize the completion of the reaction and the expected end product during the different stages of milling (Fig.9.5D). The ball-to-powder weight ratio is usually selected to be in the range between 10:1 and 50:1. The vial is then evacuated to the level of 103bar before introducing H2 gas to fill the vial with a pressure of 550bar (Fig.9.5B). The milling process is started by mounting the vial on a high-energy ball mill operated at ambient temperature (Fig.9.5C).
Tumbling mill is cylindrical shell (Fig.9.6AC) that rotates about a horizontal axis (Fig.9.6D). Hydrogen gas is pressurized into the vial (Fig.9.6C) together with Mg powders and ball-milling media, using ball-to-powder weight ratio in the range between 30:1 and 100:1. Mg powder particles meet the abrasive and impacting force (Fig.9.6E), which reduce the particle size and create fresh-powder surfaces (Fig.9.6F) ready to react with hydrogen milling atmosphere.
Figure 9.6. Photographs taken from KISR-EBRC/NAM Lab, Kuwait, show (A) the vial and milling media (balls) and (B) the setup performed to charge the vial with 50bar of hydrogen gas. The photograph in (C) presents the complete setup of GST (supplied by Evico-magnetic, Germany) system prior to start the RBM experiment for preparing of MgH2 powders, using Planetary Ball Mill P400 (provided by Retsch, Germany). GST system allows us to monitor the progress of RBM process, as indexed by temperature and pressure versus milling time (D).
The useful kinetic energy in tumbling mill can be applied to the Mg powder particles (Fig.9.7E) by the following means: (1) collision between the balls and the powders; (2) pressure loading of powders pinned between milling media or between the milling media and the liner; (3) impact of the falling milling media; (4) shear and abrasion caused by dragging of particles between moving milling media; and (5) shock-wave transmitted through crop load by falling milling media. One advantage of this type of mill is that large amount of the powders (100500g or more based on the mill capacity) can be fabricated for each milling run. Thus, it is suitable for pilot and/or industrial scale of MgH2 production. In addition, low-energy ball mill produces homogeneous and uniform powders when compared with the high-energy ball mill. Furthermore, such tumbling mills are cheaper than high-energy mills and operated simply with low-maintenance requirements. However, this kind of low-energy mill requires long-term milling time (more than 300h) to complete the gas-solid reaction and to obtain nanocrystalline MgH2 powders.
Figure 9.7. Photos taken from KISR-EBRC/NAM Lab, Kuwait, display setup of a lab-scale roller mill (1000m in volume) showing (A) the milling tools including the balls (milling media and vial), (B) charging Mg powders in the vial inside inert gas atmosphere glove box, (C) evacuation setup and pressurizing hydrogen gas in the vial, and (D) ball milling processed, using a roller mill. Schematic presentations show the ball positions and movement inside the vial of a tumbler mall mill at a dynamic mode is shown in (E), where a typical ball-powder-ball collusion for a low energy tumbling ball mill is presented in (F).
A mill is a grinder used to grind and blend solid or hard materials into smaller pieces by means of shear, impact and compression methods. Grinding mill machine is an essential part of many industrial processes, there are mainly five types of mills to cover more than 90% materials size-reduction applications.
Do you the difference between the ball mill, rod mills, SAG mill, tube mill, pebble mill? In the previous article, I made a comparison of ball mill and rod mill. Today, we will learn about the difference between SAG mill vs ball mill.
AG/SAG is short for autogenous mill and semi-autogenous mill, it combines with two functions of crushing and grinding, uses the ground material itself as the grinding media, through the mutual impact and grinding action to gradually reduce the material size. SAG mill is usually used to grind large pieces into small pieces, especially for the pre-processing of grinding circuits, thus also known as primary stage grinding machine. Based on the high throughput and coarse grind, AG mills produce coarse grinds often classify mill discharge with screens and trommel. SAG mills grinding media includes some large and hard rocks, filled rate of 9% 20%. SAG mill grind ores through impact, attrition, abrasion forces. In practice, for a given ore and equal processing conditions, the AG milling has a finer grind than SAG mills.
The working principle of the self-grinding machine is basically the same as the ball mill, the biggest difference is that the sag grinding machine uses the crushed material inside the cylinder as the grinding medium, the material constantly impacts and grinding to gradually pulverize. Sometimes, in order to improve the processing capacity of the mill, a small amount of steel balls be added appropriately, usually occupying 2-3% of the volume of the mill (that is semi-autogenous grinding).
High capacity Ability to grind multiple types of ore in various circuit configurations, reduces the complexity of maintenance and coordination. Compared with the traditional tumbling mill, the autogenous mill reduces the consumption of lining plates and grinding media, thus have a lower operation cost. The self-grinding machine can grind the material to 0.074mm in one time, and its content accounts for 20% ~ 50% of the total amount of the product. Grinding ratio can reach 4000 ~ 5000, more than ten times higher than ball, rod mill.
Ball mills are fine grinders, have horizontal ball mill and vertical ball mill, their cylinders are partially filled with steel balls, manganese balls, or ceramic balls. The material is ground to the required fineness by rotating the cylinder causing friction and impact. The internal machinery of the ball mill grinds the material into powder and continues to rotate if extremely high precision and precision is required.
The ball mill can be applied in the cement production plants, mineral processing plants and where the fine grinding of raw material is required. From the volume, the ball mill divide into industrial ball mill and laboratory use the small ball mill, sample grinding test. In addition, these mills also play an important role in cold welding, alloy production, and thermal power plant power production.
The biggest characteristic of the sag mill is that the crushing ratio is large. The particle size of the materials to be ground is 300 ~ 400mm, sometimes even larger, and the minimum particle size of the materials to be discharged can reach 0.1 mm. The calculation shows that the crushing ratio can reach 3000 ~ 4000, while the ball mills crushing ratio is smaller. The feed size is usually between 20-30mm and the product size is 0-3mm.
Both the autogenous grinding mill and the ball mill feed parts are welded with groove and embedded inner wear-resistant lining plate. As the sag mill does not contain grinding medium, the abrasion and impact on the equipment are relatively small.
The feed of the ball mill contains grinding balls. In order to effectively reduce the direct impact of materials on the ball mill feed bushing and improve the service life of the ball mill feed bushing, the feeding point of the groove in the feeding part of the ball mill must be as close to the side of the mill barrel as possible. And because the ball mill feed grain size is larger, ball mill feeding groove must have a larger slope and height, so that feed smooth.
Since the power of the autogenous tumbling mill is relatively small, it is appropriate to choose dynamic and static pressure bearing. The ball bearing liner is made of lead-based bearing alloy, and the back of the bearing is formed with a waist drum to form a contact centering structure, with the advantages of flexible movement. The bearing housing is lubricated by high pressure during start-up and stop-up, and the oil film is formed by static pressure. The journal is lifted up to prevent dry friction on the sliding surface, and the starting energy moment is reduced. The bearing lining is provided with a snake-shaped cooling water pipe, which can supply cooling water when necessary to reduce the temperature of the bearing bush. The cooling water pipe is made of red copper which has certain corrosion resistance.
Ball mill power is relatively large, the appropriate choice of hydrostatic sliding bearing. The main bearing bush is lined with babbitt alloy bush, each bush has two high-pressure oil chambers, high-pressure oil has been supplied to the oil chamber before and during the operation of the mill, the high-pressure oil enters the oil chamber through the shunting motor, and the static pressure oil film is compensated automatically to ensure the same oil film thickness To provide a continuous static pressure oil film for mill operation, to ensure that the journal and the bearing Bush are completely out of contact, thus greatly reducing the mill start-up load, and can reduce the impact on the mill transmission part, but also can avoid the abrasion of the bearing Bush, the service life of the bearing Bush is prolonged. The pressure indication of the high pressure oil circuit can be used to reflect the load of the mill indirectly. When the mill stops running, the high pressure oil will float the Journal, and the Journal will stop gradually in the bush, so that the Bush will not be abraded. Each main bearing is equipped with two temperature probe, dynamic monitoring of the bearing Bush temperature, when the temperature is greater than the specified temperature value, it can automatically alarm and stop grinding. In order to compensate for the change of the mill length due to temperature, there is a gap between the hollow journal at the feeding end and the bearing Bush width, which allows the journal to move axially on the bearing Bush. The two ends of the main bearing are sealed in an annular way and filled with grease through the lubricating oil pipe to prevent the leakage of the lubricating oil and the entry of dust.
The end cover of the autogenous mill is made of steel plate and welded into one body; the structure is simple, but the rigidity and strength are low; the liner of the autogenous mill is made of high manganese steel.
The end cover and the hollow shaft can be made into an integral or split type according to the actual situation of the project. No matter the integral or split type structure, the end cover and the hollow shaft are all made of Casting After rough machining, the key parts are detected by ultrasonic, and after finishing, the surface is detected by magnetic particle. The surface of the hollow shaft journal is Polished after machining. The end cover and the cylinder body are all connected by high-strength bolts. Strict process measures to control the machining accuracy of the joint surface stop, to ensure reliable connection and the concentricity of the two end journal after final assembly. According to the actual situation of the project, the cylinder can be made as a whole or divided, with a flanged connection and stop positioning. All welds are penetration welds, and all welds are inspected by ultrasonic nondestructive testing After welding, the whole Shell is returned to the furnace for tempering stress relief treatment, and after heat treatment, the shell surface is shot-peened. The lining plate of the ball mill is usually made of alloy material.
The transmission part comprises a gear and a gear, a gear housing, a gear housing and an accessory thereof. The big gear of the transmission part of the self-grinding machine fits on the hollow shaft of the discharge material, which is smaller in size, but the seal of the gear cover is not good, and the ore slurry easily enters the hollow shaft of the discharge material, causing the hollow shaft to wear.
The big gear of the ball mill fits on the mill shell, the size is bigger, the big gear is divided into half structure, the radial and axial run-out of the big gear are controlled within the national standard, the aging treatment is up to the standard, and the stress and deformation after processing are prevented. The big gear seal adopts the radial seal and the reinforced big gear shield. It is welded and manufactured in the workshop. The geometric size is controlled, the deformation is prevented and the sealing effect is ensured. The small gear transmission device adopts the cast iron base, the bearing base and the bearing cap are processed at the same time to reduce the vibration in operation. Large and small gear lubrication: The use of spray lubrication device timing quantitative forced spray lubrication, automatic control, no manual operation. The gear cover is welded by profile steel and high-quality steel plate. In order to enhance the stiffness of the gear cover, the finite element analysis is carried out, and the supporting structure is added in the weak part according to the analysis results.
The self-mill adopts the self-return device to realize the discharge of the mill. The self-returning device is located in the revolving part of the mill, and the material forms a self-circulation in the revolving part of the mill through the self-returning device, discharging the qualified material from the mill, leading the unqualified material back into the revolving part to participate in the grinding operation.
The ball mill adopts a discharge screen similar to the ball mill, and the function of blocking the internal medium of the overflow ball mill is accomplished inside the rotary part of the ball mill. The discharge screen is only responsible for forcing out a small amount of the medium that overflows into the discharge screen through the internal welding reverse spiral, to achieve forced discharge mill.
The slow drive consists of a brake motor, a coupling, a planetary reducer and a claw-type clutch. The device is connected to a pinion shaft and is used for mill maintenance and replacement of liners. In addition, after the mill is shut down for a long time, the slow-speed transmission device before starting the main motor can eliminate the eccentric load of the steel ball, loosen the consolidation of the steel ball and materials, ensure safe start, avoid overloading of the air clutch, and play a protective role. The slow-speed transmission device can realize the point-to-point reverse in the electronic control design. When connecting the main motor drive, the claw-type Clutch automatically disengages, the maintenance personnel should pay attention to the safety.
The slow drive device of the ball mill is provided with a rack and pinion structure, and the operating handle is moved to the side away from the cylinder body The utility model not only reduces the labor intensity but also ensures the safety of the operators.
RETSCH Vibratory Disc Mills are particularly suitable for rapid, loss-free grinding of hard, brittle and fibrous materials to analytical fineness. The mills are primarily used for sample preparation for spectral analysis. Due to their robust construction disc mills are used under rough conditions in laboratories and pilot plants, as well as online for the quality control of raw materials.
The mixing basket can hold any form of container having a maximum volume of 2 liters. The containers are fastened in place by twisted rubber rings. The basket movement is driven by elastic drive belts and an eccentric drive gear. The speed can be varied by adjusting the position of the drive belts on its 5 step pulleys. The speed can also be adjusted optional frequency converter set up next to the machine.
The mixing basket can hold up to 66 pounds in a 17 liter container. Twisted rubber clamping rings allow the use of smaller containers up to a maximum diameter of 220 mm. The movement of the mixing basket is controlled by a silent pendulum chain drive. The speed can be varied by adjusting the position of the round drive belt on the 4-step pulley.
The mixing basket can hold up to 165 pounds in a 55 liter container. Special holders must be mounted for smaller containers. These inserts are custom designed to fit the dimensions of your mixing vessel. The movement of the mixing basket is controlled by a silent pendulum chain drive and the speed can be varied by adjusting the position of the V-belt on the 5-step pulley. An extra slow speed drive is used to bring the mixing basket into its loading position. A hand cart can be purchased to help with loading.
Model equipped for both high speed revolution and a wide radius gyration, supporting for the production of high quality materials. The timing by which the revolving speed of rotation increases is controlled to improve the mixing rate of powders and liquids and sustains the generation of lumps.
90 different revolution-rotation speed patterns are available by varying the ratio of revolution and rotation. A high function model for covering from research and development to small-scale production.
A model with a vacuum reduced pressure function suited for medium-scale production. The individual revolution and rotation speed control system and wide radius gyration generate centrifugal force even at low revolving speeds, sustaining material of thermal elevation and composition change.
A high function model with a vacuum reduced pressure function. The individual revolution and rotation speed control system and the shifted cup tray enhance mixing performance and provide effective degassing.
A jet mill grinds materials by using a high speed jet of compressed air or inert gas to impact particles into each other. Jet mills can be designed to output particles below a certain size, while continue milling particles above that size, resulting in a narrow size distribution of the resulting product. Particles leaving the mill can be separated from the gas stream by cyclonic separation.
With two sharp, robust blades and apowerful 1000 W motor, it is ideal for homogenizing substances with a high water, oil or fat content as well as for grinding dry, soft and medium-hard products. Awide selection of lids and containersallows for adaptation of the mill toindividual application requirements. The GRINDOMIX GM 200 meets andexceeds all special laboratory and analytical requirementsand is a professional device superior to any commercial household mixer.
The mixer mill MM 200 is a compact versatile benchtop unit, which has been developed specially for dry grinding of small amounts of sample. It can mix and homogenize powders in only a few seconds. It is also perfectly suitable for the disruption of biological cells as well as for DNA/RNA extraction.
You may also be interested in theHigh Energy Ball Mill Emax, an entirely new type of mill for high energy input. The unique combination of high friction and impact results in extremely fine particles within the shortest amount of time.
With itsadjustable speedof 3,000 to 10,000 rpm the rotor beater mill SR 300 is intended foruniversal use: from sample preparation in laboratories up to preparing sample batches in pilot plants or production facilities. The grinding chamber, the feed hopper and the material inlet are completely made fromhigh quality stainless steel.
The SM 100 is thebudget-priced basic model among the cutting mills. With its strong 1.5 kW drive and 1,500 rpm rotor speed the mill is particularlysuitable for routine applications. Cleaning is made particularly easy.
In combination with the wide choice of bottom sieves, hoppers and collecting vessels, the mill can be easily adapted to varying application requirements. The SM 100 can be bench-mounted; alternatively a convenient base frame on wheels is available.
Cutting mills are suitable for thegrinding of soft, medium-hard, elastic, fibrous, and heterogeneous mixes of products.The new cutting mill SM 200 is a powerful and easy-to-operate instrument for efficient primary and fine size reduction.Cleaning is made particularly easy.
Within the group of the cutting mills, it is the universal standard modelwhichcovers a vast range of applicationswith its strong 2.2 kW drive and 1,500 rpm rotor speed.When operated with theoptional cyclone-suction-combination, the SM 200 is also suitable for grinding light sample materials or smaller quantities. In combination with the wide choice of bottom sieves, hoppers and collecting vessels, the mill can be easily adapted to varying application requirements.
Cutting mills are suitable for thegrinding of soft, medium-hard, tough, elastic, fibrous, and heterogeneous mixes of products.The new Cutting Mill SM 300excels especially in the tough jobswhere other cutting mills fail.
Thehigh torqueof the new 3 kW drive withRES technology(additional flywheel mass) allows for an exceptionally effective preliminary size reduction of heterogeneous mixtures, such as waste or electronic components. Analytical fineness is often achieved in one working run.
The cutting mill is used successfully for a great variety of materials. The sample is only moderately warmed up during the grinding process so that the mill is perfectly suitable forgrinding temperature-sensitive materials.Another innovation is the wide, freelyselectable speed range from 100 to 3,000 min-1.
When operated with theoptional cyclone-suction-combination, the SM 300 is also suitable for grinding light sample materials or smaller quantities. In combination with the wide choice of bottom sieves, hoppers and collecting vessels, the mill can be easily adapted to varying application requirements.
Cutting mills are suitable for thegrinding of soft, medium-hard, tough, elastic, fibrous, and heterogeneous mixes of products.The Cutting Mill SM 400 is ideally suited for pre-cutting of large sample pieces but, depending on the application, may also achieve the required fineness in one step.
The cutting mill is used successfully for a great variety of materials. The sample is only moderately warmed up during the grinding process so that the mill is perfectlysuitable for grinding temperature-sensitive materials.Due to the large open surface of the 240 mm x 240 mm bottom sieve, it is possible to grind large sample quantities and to increase the throughput.
When operated with theoptional cyclone-suction-combination, the SM 400 is also suitable for grinding light sample materials. In combination with the wide choice of bottom sieves, hoppers and collecting vessels, the mill can be easily adapted to varying application requirements.
Analysis or quality control requires finely ground samples. Easy to change grinding attachments and sieves extend the range of any samples that can be processed. Simple handling, high user safety and efficient grinding results are just a few of the advantages of this mill.
The fluid bed dryer TG 200 is used in quality control, sample preparation and R&D departments. It permits thegentle dryingof organic, inorganic, chemical or pharmaceutical bulk materialswithout localized overheating.Suitable materials can be coarse, fine, crystalline, fibrous or leafy. The powerful fan of the fluid bed dryer ensuresoptimal air throughputso that the products to be dried are loosened up and thoroughly mixed resulting inshort drying times.With the interval operation the fluidized bed is mixed even better. Temperature, drying time and air volume can be set digitally and adjusted continuously.
The PP 35 features an individual pressure force regulation in the range of 0 to 35 t. The PP 35 combines the advantage of a small bench top model with high press forces, which are built automatically in up to three steps, ensuring that even difficult materials are pressed perfectly.
The ultrasonic bath range UR includes three sizes forcleaning test sieves and grinding tools quickly and easily.UR 1 is for test sieves up to 203 mm dia., UR 2 for test sieves up to 450 mm dia., and the UR 3 for the simultaneous cleaning of up to 5 test sieves 200/203 mm dia. The gentle yet thorough cleaning of test sieves in an ultrasonic bathincreases their working livesas damage which could occur during manual cleaning is avoided.
The vibratory feeder DR 100 is used for theuniform, continuous feeding and conveyance of pourable bulk materials and fine powders. The DR 100 feeds mills, sample dividers, and particle measuring devices, and it is also suitable for other feeding tasks. Its performance, adaptability and compact design makes this device suitable for agreat variety of applications.The DR 100 can also bedriven and controlled externallyvia the built-in interface. Vibratory feeders guarantee reproducibly exact resultsand maximize the efficiency of downstream laboratory and testing devices.
Afaultless and comparable analysis is closely linked to an accurate sample handling.Only a sample representative of the initial material can provide meaningful analysis results. Sample splittersensure the representativeness of a sample and thus the reproducibility of the analysis.
The RT 100 is equipped with a feed hopper with closed outlet. Thus,up to 30 l sample materialmay be evenly spread over the entire width of the hopper. The outlet is opened manually by moving a lever and the sample is splitted. The slots of the dividing head can be adjusted to a maximum width of 108 mm.
Solid, high-quality pellets are an important precondition for reliable and meaningful XRF analysis. The PP 25 is a compact benchtop unit with particularlysimple and safe operation.With apressure force of 25 tit is ideally suited for thepreparation of solid samples for XRF analysis.The pellets produced are ofhigh qualityand are characterized by theirhigh degree of stability.The piston pressure can be read off from the clearly visible manometer scale. The dies for the Pellet Press PP 25 are available in several diameters and can be evacuated completely.
The well-proven RETSCH sieves consist of a solid stainless steel sieve frame of high stability for reliable sieving results. Paying close attention to mesh-specific requirements, the sieve fabric is precisely joined into the frame and tautened. RETSCH test sieve provides a clear and accurate labeling with full traceability.
The sieves can be easily combined with all other sieve brands. Each sieve that leaves our company comes with a test report or, at your request, with a special inspection certificate in conformity withnational and international standards (PDF). RETSCH calibration certificates confirm a great number of precision measurements, thus ensuring an even higher statistical reliability for your quality control.
The well-proven RETSCH sieves consist of a solid stainless steel sieve frame of high stability for reliable sieving results. Paying close attention to mesh-specific requirements, the sieve fabric is precisely joined into the frame and tautened. The individual laser engraving of each RETSCH test sieve provides a clear and accurate labeling with full traceability.
The sieves can be easily combined with all other sieve brands. Each sieve that leaves the company comes with a test report or, at your request, with a special inspection certificate in conformity with national and international standards (PDF). RETSCH calibration certificates confirm a great number of precision measurements, thus ensuring an even higher statistical reliability for your quality control.
The vibratory sieve shakers of the series AS 200 are used in research & development, quality control of raw materials, interim and finished products as well as in production monitoring. The controllable electromagnetic drive offers an optimal adaption for every product. Sharp fractions are obtained even after short sieving times.
The analytical sieve shakers of the series AS 200 are used in research & development, quality control of raw materials, interim and finished products as well as in production monitoring. The controllable electromagnetic drive offers an optimal adaption for every product. Sharp fractions are obtained even after very short sieving times.
With its all-digital controls, up to 99 sieving programs and calibration certificate the sieve shaker AS 200 control is indispensable for all users who attach importance to precision and operational convenience and need to comply with the guidelines of the ISO 9001.
The analytical sieve shakers of the series AS 200 are used in research & development, quality control of raw materials, interim and finished products as well as in production monitoring. The controllable electromagnetic drive offers an optimal adaption for every product. Sharp fractions are obtained even after short sieving times.
The new Air Jet Sieve AS 200 jet is particularly suitable for sieve cuts of powdered materials which require efficient dispersion and deagglomeration. The option to store up to 10 SOPs and the automatic vacuum regulator (accessory) guarantees reproducible and meaningful results.
The analytical sieve shaker AS 200 tap is used in research & development, quality control of raw materials, interim and finished products as well as in production monitoring. Its tapping motion supports the sieve analysis of certain products such as activated carbon, abrasives, metal powder, spices and diamonds, as specified in the corresponding standards.
The analytical sieve shaker AS 300 control is used in research & development, quality control of raw materials, interim and finished products as well as in production monitoring. The controllable electromagnetic drive offers an optimal adaption for every product. Sharp fractions are obtained even after short sieving times.
The AS 300 control is particularly designed for test sieves with a diameter of 305 mm (12). Compared to sieves with a diameter of 200 mm, a 2.25 times higher sieving surface is available. Therefore, the average sieving times can be greatly reduced with the AS 300 control. With its all-digital controls and calibration certificate the sieve shaker AS 300 control is indispensable for all users who attach importance to precision and operational convenience and need to comply with the guidelines of the ISO 9001.
The AS 400 control is used for the sieving of dry goods with test sieves of a diameter up to 400 mm. In this, the uniform, horizontal circular motion ensures exact separation of fine and coarse-grained products.
With its all-digital controls and calibration certificate the AS 400 control is indispensable for all users who attach importance to precision and operational convenience and need to comply with the guidelines of the ISO 9001.
The AS 450 basic, is a budget-priced alternative to the AS 450 control sieve shaker. The new sieve shaker covers a size range from 25 m to 125 mm and accepts loads of up to 15 kg. Time and amplitude are digitally set, a memory function allows storage of one program. The AS 450 basic is suitable for dry and wet sieving. It is the economic solution for customers who need to sieve larger quantities of dry material with reliable results.
The analytical sieve shaker AS 450 control is used in research & development, quality control of raw materials, interim and finished products as well as in production monitoring. The controllable electromagnetic drive offers an optimal adaption for every product. Sharp fractions are obtainable even after very short sieving times.
With the sieve shaker AS 450 control RETSCH have designed their first sieve shaker for 400 mm and 450 mm sieves which operates with a three-dimensional sieving motion. It can be used for dry and wet sieving. The optimized electromagnetic drive technology allows for an amplitude up to 2.2 mm even with maximum loads up to 25 kg. This makes the AS 450 superior to all other known sieve shakers based on conventional electromagnetic or imbalance drives.
Applications: It is mainly used in the processing of fine powder and ultrafine powder in metallurgy, mining, building materials, chemical industry, refractory materials, abrasives, graphite, glass, ceramics and other industries.
Vibration ball mill, also known as a vibrating ball mill or vibratory ball mill, is a kind ofball mill machinethat uses the high-frequency vibration of the cylinder to make the grinding medium in the cylinder impact the material by inertial force.
Vibration ball mill is a new type of high-efficiency and energy-saving grinding equipment. It has obvious advantages over traditionalrotary ball millin grinding fine and ultra-fine powder materials. The grinding efficiency of vibrating ball mill can be increased by 2-5 times, and energy consumption can be reduced by 20% 30%.
Vibration ball mill can be widely used in fine powder and ultrafine powder processing in ore dressing, building materials, abrasive materials, chemical raw materials, metallurgy, electric power, special ceramics, refractory materials and other industries. In recent years, the vibration mill has been widely used in the magnesium industry because it solves the problem of powder sticking and grinding in the production process.
When the vibratory ball mill is in operation, the motor drives the vibrator with the eccentric hammer to do the axial rotation motion, which causes the barrel to vibrate. The medium and materials are turned and dropped in the barrel, and the materials are crushed under the impact force.
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.
A bench type versatile mill for small samples that require accurate and consistent particle size reduction. To operate, the user simply fills the bowl with the sample and a charge of balls. The bowl is then closed with a quick release lid.
Cement plant is necessary for cement production, mainly consist of a series of cement equipment apply for preparation of cement raw materials, clinker production, and finished cement production, such as cement mill, cement crusher, rotary kiln, cement roller press, cement dryer, clinker cooler, cement silo, and related cement plant equipment. AGICO CEMENT is a cement plant manufacturer who owns ability to manufacture cement equipment and provide EPC turnkey project for cement plant.
AGICO Cement is a cement plant manufacturer with production capacity of 30,000 tons of equipments and structure parts and 20,000 tons of casting parts.own production equipment of 8m Vertical Lathe, 10m gear rolling machine, 8m Gantry milling machine, 200mm floor-type boring and milling machine,1203200mm bending machine, 150t crane and 40t electric furnace.
The brand ZKL was founded in the year 1921 in the then Czechoslovakia in Central Europe, and is more than 90 years old. Today, ZKL Brand is owned by ZKL a.s, Brno, the Czech Republic. ZKL Brand of bearings and Bearing Accessories enjoy the largest market share in the Central Europe, and is considered to be one of the topmost names amongst the bearing brands manufactured all over the world.
The Vibratory Micro Mill Pulverisette 0 grinds your sample through impact and friction by which the mortar vibrates electromagnetically and the grinding material transfers the vibrations to the grinding ball.
At the beginning of the grinding, the crushing of the coarse particles is achieved by the impact effect of the grinding ball. Next, the fine particles are ground through friction by the tumbling motion of the grinding ball as the vibrations subside.
For fast embrittlement of soft, slightly oily, fatty or moist materials for cryogenic grinding, we offer the cryo-box: simply insert the filled grinding set into the cryo-box and fill it with liquid nitrogen. With this method even extremely difficult-to-grind samples can be ground down to analytical fineness. And the thick insulation ensures a particularly efficient use of coolant.
This Mill can be converted to a Vibratory Sieve Shaker for quantitative particle size analysis of solids (measuring range 32 m 63 m) and suspensions (measuring range 20 m 10 mm) by simply inserting corresponding sieves.
Maximum feed size: 5 mm Final fineness: down to 10 m (depending on material) Maximum capacity: 10 ml Grinding materials: agate, sintered corundum, zirconium oxide, stainless steel, tempered steel, tungsten carbide Dimensions (WxDxH): bench top instrument 37x40x20 cm (15x16x8) Weight: 21 kg (46 lb.) Certified safety (CE mark) optional CSA approval for Canada 2-year warranty
The Vibratory Micro Mill Pulverisette 0 achieves size reduction through the combination of impact and friction. An electromagnetically powered mortar generates vibrations. These vibrations are transferred to the grinding ball via the grinding material. The impact energy of the grinding ball can be controlled to suit the application.
The Vibratory Micro Mill Pulverisette 0 achieves size reduction through the combination of impact and friction. An electromagnetically powered mortar generates vibrations. These vibrations are transferred to the grinding ball via the grinding material. The impact energy of the grinding ball can be controlled to suit the application.
The Planetary Ball Mill Pulverisette 5 allows fast and very fine grinding of hard to soft material, dry or in suspension, down to colloidal fineness. It can also be used for mixing and homogenising of emulsions and pastes. Grinding capacity of up to 8 samples per operation.
The Vario Planetary Mill Pulverisette 4 is ideal for mechanical activation and alloying.It offers thefreedom toprogramall grinding parametersthroughPC software to achieve the desired effect on the sample.
The Planetary Micro Mill Pulverisette 7 is designed for uniform, and extremely fine size reduction of very small samples of hard to soft material, dry or in suspension, down to colloidal fineness. Also designed for mixing and homogenising of emulsions or pastes.
General Kinematics VIBRA-DRUM Grinding Mills are proven in dozens of milling applications in the mining and mineral industries. Because of this flexibility, they are the perfect solution for your needs, no matter the grinding processes you use.
Each grinding mill is achieving impressive energy savings (35-50%), thanks to a unique rotational material motion that is more efficient than conventional ball or rotary grinding mills. New processes such as micron grinding and mechanochemical grinding give our customers a unique and effective competitive advantage.
VIBRA-DRUM Grinding Mill units are also ideal for continuous processing of difficult-to-fluidize products such as large flake and stringy or tacky materials. Typical VIBRA-DRUM Grinding Mill applications include direct gas contact heating, drying, cooling, and coating. Need more information about the General Kinematics VIBRA-DRUM Grinding Mills? Ask our experts!
The capital cost of a VIBRA-DRUM Grinding Mill is significantly less than a rotary grinding mill containing a comparable media load. Some of the VIBRA-DRUM Grinding Mill features to keep installation costs low include:
Minimal moving parts and innovative engineering combine to provide you with a grinding mill that requires little maintenance and downtime requirements. The maintenance of the VIBRA-DRUM products is simple and consists of:
Exceptional grinding performance and energy savings are the result of the VIBRA-DRUM natural frequency design. A sub-resonant, two mass drive and spring system alternately stores and releases grinding power. Once in motion, energy is only needed to move the grinding media as a fluid mass, and to overcome frictional losses.
The increased number of impacts in our VIBRA-DRUM Grinding Mills result in a faster, more efficient grinding action. As the grinding mill vibrates, media particle migration is experienced in both axial and transverse directions. In fact, the media migrates through the VIBRA-DRUM Grinding Mill in a path similar to that of a rotary grinding mill without lifters, but each media particle imparts positive impact energy at each vibration.
The area where comminution takes place is larger and more efficient compared to a rotary grinding mill of similar size. There are no dead zones of inactive media inside the vibrating grinding mill. And, unlike stirred or tower grinding mills which grind by attrition, the VIBRA-DRUM Grinding Mill uses the principle of impact grinding which causes clean breaking and doesnt coat the mineral/gangue with slimes.
VIBRA-DRUM Grinding Mills excel over conventional ball, stirred media, or vertical roller mills in both grinding and energy efficiency. The features listed below highlight why our mills are so effective and efficient.
The capabilities of the VIBRA-DRUM Grinding Mill are unmatched. Extensive in-house or on-site testing is available to qualify your product requirements. General Kinematics also offers wet or dry particle analysis as well as access to our on-staff material scientist for further material qualification.
Challenge Traditional grinding mills reclaim only a fraction of precious metals from ore, leaving valuable material in the tailings. These minerals are more difficult to liberate, as it requires the...
Vibratory Disc Mill is mainly used for sample preparation of spectral analysis. The device is especially suitable for fast medium-hard, brittle and fibrous materials to analytical fineness grinding without loss. ...
45 ton Force hydraulic Vibratory Hammer Maker: Tomen Japan, Model: SS40L, YOM: 1990yr, S.N. S40U-01054, Hydraulic Power Unit, , attached. Used and located in Japan/working condition Capacity: 20 to 473 Hz, 1200...
Product Description Desktop High Energy Vibratory Ball Mill with One St St Jar Features Desktop High Energy Vibratory Ball Mill with One St St Jar may be referred to as shaker mills, mixer mills or high-energy ba...
The Vibratory Disc Mill RS 200 is suitable for the extremely quick, loss-free and reproducible grinding of medium-hard, brittle and fibrous materials to analytical fineness. The instrument runs steadily and smoot...
The Vibratory Disc Mill RS 300 is suitable for the extremely quick, loss-free and reproducible grinding of medium-hard, brittle and fibrous materials to analytical fineness. It is possible to process 1, 2, 3 or 4...
Vibratory Sieve in Crushinf Process (30-40t/h) Process Description: During the production and business activities in the mining enterprises,the production process is closely related to the efficient profits for e...
USED CME SCR2555D DOUBLE DECK SCREENER 15-Day Right of Return Manufactured by Colorado Mill Equipment Used less than 100 Hrs, Unit reported in excellent condition Equipped with a 3 HP, 1115 RPM, 230/460V, 60Hz mo...
Copeland Stainless Steel Mill, with vibratory feeder and mobile stand . Please read the following important notes:- Assistance will be given with loading where possible by vendor All lots are sold Ex Works (EXW),...
Model DM10 Vibratory Grinding Mill Sweco DM10 Vibratory Mill, dry grinding, urethane lining, top cover, approximately 10 cubic foot capacity, 1000 lbs. normal media load, 5 hp motor STOCK NUMBER: DPM-2037
Dual Chamber Vibratory Shaker Mill Seibtechnik Vibratory Lab Ball Mill one(1) used Seibtechnik Vibratory Lab Ball Mill Model 20168 Serial number 43888 Two grinding chambers, with removable lids. STOCK NUMBER: DPM...
MODEL DM20L Vibratory Grinding Mill Sweco DM20L Vibratory Grinding Mill, urethane lining, top cover, two air assist discharge covers, 10 hp motor, 460 volt, 20 cubic foot capacity, 2000 lb. normal media load-Medi...
A vibration mill is a size reduction equipment that applies the process of continuous impaction in carrying out its size reduction function. The grinding container is made up of a tube that is held in a frame that is supported by means of springs which is filled to approximately 80% total volume with porcelain or stainless steel balls.
During milling, the entire body of the mill undergoes a small but frequent vibration that is generated by an eccentric motor, and size reduction occurs by repeated impact. This vibration is usually, but not necessarily, in a vertical plane.
Drugs and excipients are readily ground to less than 5 mm, the grinding time being considerably less than is required in normal ball milling. As a result, the efficiency of the comminution process in vibratory milling is a good deal than it is in conventional ball milling.
Wow, I had no idea that there were so many advantages to using vibration mills for milling. Although, I suppose it makes sense since there is a higher grinding rate for particles. That is definitely something to keep in mind if I ever need to do any milling for the projects that Ive been working on lately.
We are looking a replacing our dry product vibration plants ball mills. They are very old, and we do not even know who the OEM was. We are looking for a mill that can handle 100- 300kg of product as a batch. On completion of the mill cycle it must be able to discharge the product quickly and easily.(automated) We need to be able to sustain a production throughput of 200kg/hr. Bulk density is 0.4Kg/litre. Material: Zeolite powder. I represent a company called Clariant in Richards Bay, South Africa Regards Shaun McMillan
Hello Shaun, You can contact manufacturers and suppliers of pharmaceutical machines on our pharma marketplace using this link https://.ads.pharmapproach.com. They will be in the best position to provide you with the necessary information you need. Regards