simple introduction of lattice type ball mill
Ball mill is the key equipment for secondary grinding after crushing. And it is suitable for grinding all kinds of ores and other materials, no matter wet grinding or dry grinding. Besides, it is mainly applied in many industries, such as ferrous&non-ferrous metal mine, building materials, chemical, electric power, coal, traffic, light industry, etc.
And lattice-type ball mills is a common type of ball mill. It is also a beneficiation equipment. It is one of the main equipments for grinding various metal mineral materials. lattice-type ball mills is an important ore processing equipment in industries such as industry and metallurgy industry. As a professional manufacturer of ore processing machinery and equipment, Shanghai Joyal Mining Machinery Co., Ltd. is here to talk about the advantages and disadvantages of lattice-shaped ball mills.
lattice-type ball mills can grind most of the materials and can be continuously produced without interruption. The use of lattice-type ball mills is very extensive and the yield is also high. The development of lattice-type ball mills is not short due to many years of use by users. Use, and technical personnel are not short-term improvement and optimization, so lattice-shaped ball mill technology is constantly improving.
There are few problems with the lattice-type ball mills. Some problems are not only solved by the technicians, but also by some production workers. The lattice ball mill has a large comminution ratio and can grind up to 300 meshes. The grain size of the material can also be adjusted. In operation, the power consumption is low, and the energy consumption is low.
Of course, lattice-type ball mills also have some problems that require everyone's attention. The installation of the lattice type ball mill requires high requirements for the factory buildings, and the general land cannot be used because the equipment is heavy and the foundation is not stable enough. The machine will sink into the ground when the production operation is performed; and the price of the lattice ball mill is comparable to other equipment may be slightly more expensive.
Classification of Energy-saving Ball Mill: Energy-saving ball mill for grinding various ores and other materials, are widely used in mineral processing, building materials and chemical industry can be divided into dry and wet grinding. According to different ways of discharge can be divided into the two types---lattice type and overflow type. Application of Energy-saving Ball Mill: Energy-saving b
joyal-ball mill,ball mill for sales,ball mill manufacturer
Ball mill is the key equipment for secondary grinding after crushing. And it is suitable for grinding all kinds of ores and other materials, no matter wet grinding or dry grinding. Besides, it is mainly applied in many industries, such as ferrous&non-ferrous metal mine, coal, traffic, light industry, etc.
The Ball mill can be divided into lattice type and overflow type according to different beneficiation methods, and this machine is two lattice-type ball mill.
The materials from the feeding fittings enter the first bin of the milling machine via the feeding hollow axis evenly when it works. There is a ladder-like or ripple-like scaleboard in the first bin, and different specification steel balls are installed in the bin. When the cylinder rotates, which generating centrifugal force to carries steel balls to a certain height and then balls fall to strike and grind the material. After primary grinding in the first bin, the material then enters into the second bin via a single layer partition board. There is a scaleboard and steel balls in the second bin, so the materials are further ground. In the end, the powder is discharged by output material board.
ball mill, ball grinding mill - all industrial manufacturers - videos - page 2
RAPID MILL WITH PLANETARY DRIVE, "MAGELLANO" SERIES, MOD. MAG3000/C WITH 4 ROTATING UNIT The requirement of some laboratories in the ceramic industry to be able to rapidly grind large frit quantities, led Ceramic ...
... Convenient in maintenance.
The Ball mill 9001800 can be divided into lattice type and overflow type according to different beneficiation methods, and this machine is two lattice-type ...
High operational reliability, stable performance, simple structure and easy maintenance.
Model with speed controller available.(Model : J-BM1-S)
Displays realtime operation speed utilizing rpm meter.(Model : J-BM1-S)
The Laboratory Ball Mill is primarily designed for grinding pigments and cement. The material is
ground at a specific speed for a specific period using a specific quantity of grinding steel balls. ...
grinding mill design & ball mill manufacturer
All Grinding Mill & Ball Mill Manufacturers understand the object of the grinding process is a mechanical reduction in size of crushable material. Grinding can be undertaken in many ways. The most common way for high capacity industrial purposes is to use a tumbling charge of grinding media in a rotating cylinder or drum. The fragmentation of the material in that charge occurs through pressure, impact, and abrasion.
The choice of mill design depends on the particle size distribution in the feed and in the product wanted. Often the grinding is more economic when executed in a primary step, followed by a secondary step, giving a fine size product.
C=central trunnion discharge P=peripheral discharge R=spherical roller trunnion bearing, feed end H=hydrostatic shoe bearing, feed end R=spherical roller trunnion bearing, discharge end K=ring gear and pinion drive
Type CHRK is designed for primary autogenous grinding, where the large feed opening requires a hydrostatic trunnion shoe bearing. Small and batch grinding mills, with a diameter of 700 mm and more, are available. These mills are of a special design and described on special request by allBall Mill Manufacturers.
The different types of grinding mills are based on the different types of tumbling media that can be used: steel rods (rod mills), steel balls (ball mills), and rock material (autogenous mills, pebble mills).
The grinding charge in a rod mill consists of straight steel rods with an initial diameter of 50-100 mm. The length of the rods is equal to the shell length inside the head linings minus about 150 mm. The rods are fed through the discharge trunnion opening. On bigger mills, which need heavy rods, the rod charging is made with a pneumatic or manual operated rod charging device. The mill must be stopped every day or every second day for a few minutes in order to add new rods and at the same time pick out broken rod pieces.
As the heavy rod charge transmits a considerable force to each rod, a rod mill can not be built too big. A shell length above 6100 mm can not be recommended. As the length to diameter ratio of the mill should be in the range of 1,2-1,5, the biggest rod mill will convert maximum 1500 kW.
Rod mills are used for primary grinding of materials with a top size of 20-30 mm (somewhat higher for soft materials). The production of fines is low and consequently a rod mill is the right machine when a steep particle size distribution curve is desired. A product with 80% minus 500 microns can be obtained in an economical manner.
The grinding charge in a ball mill consist of cast or forged steel balls. These balls are fed together with the feed and consequently ball mills can be in operation for months without stopping. The ball size is often in the diameter range of 20-75 mm.
The biggest size is chosen when the mill is used as a primary grinding mill. For fine grinding of e.g. sands, balls can be replaced by cylpebs, which are heat treated steel cylinders with a diameter of 12-40 mm and with the same length as the diameter.
Ball mills are often used as secondary grinding mills and for regrinding of middlings in concentrators. Ball mills can be of the overflow or of the grate discharge type. Overflow discharge mills are used when a product with high specific surface is wanted, without any respect to the particle size distribution curve. Overflow discharge mills give a final product in an open circuit. Grate discharge mills are used when the grinding energy shall be concentrated to the coarse particles without production of slimes. In order to get a steep particle size distribution curve, the mill is used in closed circuit with some kind of classifier and the coarse particles known as classifier underflow are recycled. Furthermore, it should be observed that a grate discharge ball mill converts about 20% more energy than an overflow discharge mill with the same shell dimensions.
Ball mill shells are often furnished with two manholes. Ball mills with small balls or cylpebs can produce the finest product of all tumbling mills. 80% minus 74 microns is a normal requirement from the concentrators.The CRRK series of wet grinding ball mills are tabulatedbelow.
No steel grinding media is used in a fully autogenous mill. When choosing primary autogenous grinding, run of mine ore up to 200-300 mm in size is fed to the mill. When using a crushing step before the grinding, the crusher setting should be 150-200 mm. The feed trunnion opening must be large enough to avoid plugging. The biggest pieces in the mill are important for the size reduction of middle size pieces, which in their turn are important for the finer grinding. Thus the tendency of the material to be reduced in size by pressure, impact, and abrasion is a very important question when primary autogenous grinding is proposed.
When autogenous grinding is used in the second grinding step, the grinding media is size-controlled and often in the range of 30-70 mm. This size is called pebbles and screened out in the crushing station and fed to the mill in controlled proportion to the mill power. The pebble weight is 5-25% of the total feed to the plant, depending on the strength of the pebbles. Sometimes waste rock of high strength is used as pebbles.
Pebble mills should always be of the grate discharge type. The energy that can be converted in a mill depends on the total weight of the grinding charge. Consequently, pebble mills convert less power per mill volume unit than rod and ball mills.
High quality steel rods and balls are a considerable part of the operating costs. Autogenous grinding should, therefore, be considered and tested when a new plant shall be designed. As a grinding mill is built to last for decades, it is more important to watch the operation costs than the price of the mill installation. The CRRK series of wet grinding pebble mills are tabulated below.
Wet grinding is definitely the most usual method of grinding minerals as it incorporates many advantages compared to dry grinding. A requirement is, however, that water is available and that waste water, that can not be recirculated, can be removed from the plant without any environmental problems. Generally, the choice depends on whether the following processing is wet or dry.
When grinding to a certain specific surface area, wet grinding has a lower power demand than dry grinding. On the other hand, the wear of mill lining and grinding media is lower in dry grinding. Thus dry grinding can be less costly.
The feed to a dry grinding system must be dried if the moisture content is high. A ball mill is more sensitive to clogging than a rod mill. An air stream through the mill can reduce the moisture content and thus make a dry grinding possible in certain applications.
Due to the hindering effect that the ball charge gives to the material flow in dry grinding, the ball charge is not more than 28-35% of the mill volume. This should be compared with 40-45% in wet grinding. The expression used for this phenomenon is that the charge in a dry grinding mill is swollen.
Big dry grinding ball mills are often two-compartment mills, with big balls in the first compartment and small balls or cylpebs in the second one. An extra grate wall is used to separate the two charges.
The efficiency of wet grinding is affected by the percentage of solids. If the pulp is too thick, the grinding media becomes covered by too thick a layer of material, which hinders grinding. The opposite effect may be obtained if the dilution is too high, and this may also reduce the grinding efficiency. A high degree of dilution may sometimes be desirable in order to suppress excessive slime formation.
The specific power required for a certain grinding operation, usually expressed in kWh/ton, is a function of both the increase in the specific surface of the material (expressed in cm/cm or cm/g) and of the grinding resistance of the material. This can be expressed by the formula
where c is a material constant representing the grinding resistance, and So and S are the specific surfaces of the material before and after the grinding operation respectively. The formula is an expression of Rittingers Law which is shown by tests to be reasonably accurate up to a specific surface of 10,000 cm/cm.
When the grinding resistance c has been determined by trial grinding to laboratory scale, the net power E required for each grinding stage desired may be determined by the formula, at least as long as Rittingers Law is valid. If grinding is to be carried out not to a certain specific surface S but to a certain particle size k, the correlation between S and k must be determined. The particle size is often expressed in terms of particle size at e.g. 95, 90 or 80% quantity passing and is denoted k95, k90 or k80.
where E =the specific power consumption expressed in kWh/short ton. Eo = a proportionality and work factor called work index k80p = particle size of the product at 80% passage (micron) k80f =the corresponding value for the raw material (micron)
The value of Eo is a function of the physical properties of the raw material, the screen analyses of the product and raw material respectively, and the size of the mill. The value for easily-ground materials is around 7, while for materials that have a high grinding resistance the value is around 17.
Eo is correlated to a certain reduction ratio, mill diameter etc. Corrections must be made for each case. The simplest method of calculating the specific power consumption is test grinding in a laboratory mill, and comparison of the results with a known reference material. The sample is ground in batches for 3, 6,12 minutes, a screen analysis is carried out after each period, after which the specific surface is determined. A good estimate of the grinding characteristics of the sample can be obtained by comparison of the specific surfaces with corresponding values for the reference material.
When the net power required has been determined, an allowance is made for mechanical losses. The gross power requirement thus arrived at, should with a satisfactory margin be utilised by the mill selected.
The critical speed of a rotating mill is the RPM at which a grinding medium will begin to centrifuge, namely will start rotating with the mill and therefore cease to carry out useful work. This will occur at an RPM of ncr, which may be determined by the formula
where D is the inside diameter in meters of the mill. Mills are driven in practice at a speed corresponding to 60-80% of the critical speed, the choice of speed being influenced by economical considerations. Within that range the power is nearly proportional to the speed.
The charge volume in the case of rod and ball mills is a measure of the proportion of the mill body that is filled by rods or balls. When the mill is stationary, raw material and liquid should fill the voids between the grinding media, in order that these should be fully utilized.
Maximum mill efficiency is reached at a charge volume of approximately 55%, but for a number of reasons 45-50% is seldom exceeded. The efficiency curve is in any case quite flat about the maximum. In overflow mills the charge volume is usually 40%, while there is a greater choice in the case of grate discharge mills.
For coarse grinding in rod mills, the rods used have a diameter of 50-100 mm and their lengths are approx. 150 mm below the effective inside shell length. Rods will break when they have been worn down to about 20 mm and broken rods must from time to time be taken out of the mill since otherwise they will reduce the mill capacity and may cause blockage through piling up. The first rod charge should also contain a number of rods of smaller diameter.
It may be necessary to charge the mill with rods of smaller diameter when fine grinding is to be carried out in a rod mill. Experience shows that the size of the grinding media should bear a definite relationship to the size of both the raw material and the finished product in order that optimum grinding may be achieved. The largest grinding media must be able to crush and grind the largest pieces of rock, while on the other hand the grinding media should be as small as possible since the total active surface increases in inverse proportion to the diameter.
A crushed mineral whose largest particles pass a screen with 25 x 25 mm apertures shall be ground to approx. 95% passing 0.1 mm in a 2.9 x 3.2 m ball mill of 35 ton charge weight. In accordance with Olewskis formula
Grinding media wear away because of the attrition they are subjected to in the course of the grinding operation, and in addition a continuous reduction in weight takes place owing to corrosion. The rate of wear will in the first place depend on the abrasive properties of the mineral being ground and naturally also on the hardness of the grinding media themselves.
The wear of rods and balls is usually quoted in grammes per ton of material processed (dry weight) and normal values may lie between 100 and 1500 g/ton. Considerably higher wear figures may however be experienced in fine wet grinding of e.g. very hard siliceous sand.
A somewhat more accurate way of expressing wear is to state the amount of gross kWh of grinding power required to consume 1 kg of grinding media. A normal value in wet grinding is 15 kWh/kg.The wear figures in dry grinding are only 10-30 % of the above.
where c is a constant which, inter alia, takes into consideration the mean slope a of the charge, W is the weight in kp of the charge n is the RPM Rg is the distance in metres of the centre of gravity from the mill centre
W for rod and ball mills shall be taken as the weight of the rod or ball charge, i.e. the weight of the pulp is to be ignored. For pebble mills therefore W is to be calculated on the basis of the bulk weight of the pebbles.
It should be pointed out that factor c in the formula is a function of both the shape of the inner lining (lifter height etc.) and the RPM. The formula is however valid with sufficient accuracy for normal speeds and types of lining.
The diagram gives the values of the quantity Rg/d as a function of the charge volume, the assumption being that the charge has a plane surface and is homogeneous, d is the inside diameter of the mill in metres. The variation of the quantity a/d, where a is the distance between the surface of the charge and the mill centre, is also shown in the same figure.
In order to keep manufacturing costs at a minimum level, Morgardshammar has a series of standard mill diameters up to and including 6.5 m. Shell length, however, can be varied and tailor made for each application. The sizes selected are shown on the tables on page 12-13 and cover the power range of 200-5000 kW.
Shells with a diameter of up to about 4 m are made in one piece. Above this dimension, the shell is divided into a number of identical pieces, bolted together at site, in order to facilitate the transport. The shell is rolled and welded from steel plate and is fitted with welded flanges of the same material. The flanges are machined in order to provide them with locating surfaces fitting into the respective heads. The shells of ball and pebble mills are provided with 2 manholes with closely fitting covers. The shells have drilled holes for different types of linings.
Heads with a diameter of up to about 4 m are integral cast with the trunnion in one piece. Above this diameter the trunnion is made as a separate part bolted to the head. The head can then be divided in 2 or 4 pieces for easy transport and the pieces are bolted together at site. The material is cast steel or nodular iron. The heads and the trunnions have drilled holes for the lining.
Spherical roller (antifriction) bearings are normally used. They offer the most modern and reliable technology and have been used for many years. They are delivered with housings in a new design with ample labyrinth seals.
For very large trunnions or heavy mills, i.e. for primary autogenous grinding mills. Morgardshammar uses hydrostatic shoe bearings. They have many of the same advantages as roller bearings. They work with circulating oil under pressure.
The spherical roller bearing and the hydrostatic shoe bearing take a very limited axial space compared to a conventional sleeve bearing. This means that the lever of the bearing load is short. Furthermore, the bending moment on the head is small and as a result of this, the stress and deformation of the head are reduced. Ask Morgardshammar for special literature on trunnion bearings.
Ring gears are often supplied with spur gears. They are always split in 2 or 4 pieces in order to facilitate the assembly. Furthermore, they are symmetrical and can be turned round in order to make use of both tooth flanks. The material is cast steel or nodular iron. They are designed in accordance with AGMA.The ring gear may be mounted on either the feed or the discharge head. It is fitted with a welded plate guard.
The pinion and the counter shaft are integral forged and heat treated of high quality steel. For mill power exceeding about 2500 kW two pinions are used, one on each side of the mill (double-drive). The pinion is supported on two spherical roller bearings.
The trunnion bearings are lubricated by means of a small motor- driven grease lubricator. The gear ring is lubricated through a spray lubricating system, connected to the electric and pneumatic lines. The spray nozzles are mounted on a panel on the gear ring guard.
In order to protect the parts of the mill that come into contact with the material being ground, a replaceable lining of wear-resistant material is fitted. This may take the form of unalloyed or alloyed rolled or cast steel, heat treated if required, or rubber of the appropriate wear resistant quality. White cast iron, unalloyed or alloyed with nickel (Ni-hard), may also be used.
The shape of the mill lining is often of Lorain-type, consisting of plates held in place between lifter bars (or key bars) of suitable height bolted on to the shell. This system is used i.e. of all well-known manufacturers of rubber linings. Ball mills and autogenous mills with metal lining also can be provided with single or double waved plates without lifter bars.
In grate discharge mills the grate and the discharge lifters are a part of the lining. The grate plates with tapered slots or holes are of metal or rubber design. The discharge lifters are fabricated steel with thick rubber coating. Rubber layer for metal linings and heavy corner pieces of rubber are included in a Morgardshammar delivery as well as attaching bolts, washers, seal rings, and self-locking nuts. A Morgardshammar overflow mill can be converted into a grate discharge mill only by changing some liner parts and without any change of the mill. Trunnion liners are rubber coated fabricated steel or cast steel. In grate discharge mills the center cone and the trunnion liner form one piece.
Scoop feeders in combination with drum feeders are used when retaining oversize from a spiral or rake classifier. As hydrocyclones are used in most closed grinding circuits the spout feeders are used most frequently.
Vibrating feeders or screw feeders are used when charging feed to dry grinding mills. Trommel screens are used to protect slurry pumps and other transport equipment from tramp iron. Screens can have perforated rubber sheets or wire mesh. The trommel screens are bolted to the discharge trunnion lining.
Inching units for slow rotation of the mills are also furnished. Rods to the rod mills are charged by means of manual or automatic rod charges. Erection cradles on hydraulic jacks are used when erecting medium or big size mills at site.
A symbol of dependable quality ore milling machinery manufacturing, industrial and mining equipment, ball mills and rod mills as well as supplies created for your specific needs. During this period thousands of operators have experienced continuous economical and unequalled service through their use.As anindustrial ball mill manufacturer and supplier, we havecontinuously accumulated knowledge on grinding applications. It has contributed greatly to the grinding process through the development and improvement of such equipment.
Just what is grinding? It is the reduction of lump solid materials to smaller particles by the application of shearing forces, pressure, attrition, impact and abrasion. The primary consideration, then, has been to develop some mechanical means for applying these forces. The modern grinding mill applies power to rotate the mill shell and thus transmits energy to some form of media which, in turn, fractures individual particles.
Through constant and extensive research, in the field of grinding as well as in the field of manufacturing. Constantly changing conditions provide a challenge for the future. Meeting this challenge keeps our company young and progressive. This progressive spirit, with the knowledge gained through the years, assures top quality equipment for the users of our mills.
You are urged to study the following pages which present a detailed picture of our facilities and discuss the technical aspects of grinding. You will find this data helpful when considering the selection of the grinding equipment.
It is quite understandable that wetakes pride in the quality of our mills.Complementing the human craftsmanship built into these mills, our plants are equipped with modern machines of advanced design which permit accurate manufacturing of each constituent part. Competent supervision encourages close inspection of each mill both as to quality and proper fabrication. Each mill produced is assured of meeting the high required standards. New and higher speed machines have replaced former pieces of equipment to provide up-to-date procedures. The use of high speed cutting and drilling tools has stepped up production, thereby reducing costs and permitting us to add other refinements and pass these savings on to you, the consumer.
Each foundry heat is checked metallurgically prior to pouring. All first castings of any new design are carefully examined by the use of an X-ray machine to be certain of uniformity of structure. The X -ray is also used to check welding work, mill heads, and other castings.
Each Mills, regardless of size, is designed to meet the specific grinding conditions under which it will be used. The speed of the mill type of liner, discharge arrangement, size of feeder, size of bearings, mill diameter and length, and other factors are all considered to take care of the size of feed, tonnage, circulating sand load, selection of balls or rods, and the final size of grind.
All Mills are built with jigs and templates so that any part may be duplicated. A full set of detailed drawings is made for each mill and its parts. This record is kept up to date during the life of the mill. This assures accurate duplication for the replacement of wearing parts during the future years.
As a part of our service our staff includes experienced engineers, trained in the field of metallurgy with special emphasis on grinding work. This knowledge, as well as a background gained from intimate contact with various operating companies throughout the world, provides a sound basis for consultation on your grinding problems. We take pride in manufacturing rod mills and ball millsfor the metallurgical, rock products, cement, process, and chemical industries.
As an additional service we offer our testing laboratories to check your material for grindability. Since all grinding problems are different some basis must be established for recommending the size and type of grinding equipment required. Experience plays a great part in this phase however, to establish more direct relationships it is often essential to conduct individual grindability tests on the specific material involved. To do this we have established certain definite procedures of laboratory grinding work to correlate data obtained on any new specific material for comparison against certain standards. Such standards have been established from conducting similar work on material which is actually being ground in Mills throughout the world. The correlation between the results we obtain in our laboratory against these standards, coupled with the broad experience and our companys background, insures the proper selection and recommendation of the required grinding equipment.
When selecting a grinding mill there are many factors to be taken into consideration. First let us consider just what constitutes a grinding mill. Essentially it is a revolving, cylindrical shaded machine, the internal volume of which is approximately one-half filled with some form of grinding media such as steel balls, rods or non-ferrous pebbles.
Feed may be classified as hard, average or soft. It may be tough, brittle, spongy, or ductile. It may have a high specific gravity or a low specific gravity. The desired product from a mill may range in size from a 4 mesh down to 200 mesh, or into the fine micron sizes. For each of these properties a different mill would be indicated.
The Mill has been designed to carry out specific grinding work requirements with emphasis on economic factors. Consideration has been given to minimizing shut-down time and to provide long, dependable trouble-free operation. Wherever wear takes place renewable parts have been designed to provide maximum life. A Mill, given proper care, will last indefinitely.
Mills have been manufactured in a wide variety of sizes ranging from laboratory units to mills 12 in diameter, with any suitable length. Each of these mills, based on the principles of grinding, provides the most economical grinding apparatus.
For a number of years ball mill grinding was the only step in size reduction between crushing and subsequent treatment. Subsequently smaller rod mills have altered this situation, providing in some instances a more economical means of size reduction in the coarser fractions. The principal field of rod mill usage is the preparation of products in the 4-mesh to 35-mesh range. Under some conditions it may be recommended for grinding to about 48 mesh. Within these limits a rod mill is often superior to and more efficient than a ball mill. It is frequently used for such size reduction followed by ball milling to produce a finished fine grind. It makes a product uniform in size with only a minimum amount of tramp oversize.
The basic principle by which grinding is done is reduction by line contact between rods extending the full length of the mill. Such line contact results in selective grinding carried out on the largest particle sizes. As a result of this selective grinding work the inherent tendency is to make size reduction with the minimum production of extreme fines or slimes.
The small rod mill has been found advantageous for use as a fine crusher on damp or sticky materials. Under wet grinding conditions this feed characteristic has no drawback for rod milling whereas under crushing conditions those characteristics do cause difficulty. This asset is of particular importance in the manufacture of sand, brick, or lime where such material is ground and mixed with just sufficient water to dampen, but not to produce a pulp. The rod mill has been extensively used for the reduction of coke breeze in the 8-mesh to 20-mesh size range containing about 10% moisture to be used for sintering ores.
Grinding by use of nearly spherical shaped grinding media is termed ball milling. Strictly speaking, such media are made of steel or iron. When iron contamination is detrimental, porcelain or natural non-metallic materials are used and are referred to as pebbles. When ore particles are used as grinding media this is known as autogenous grinding.
Other shapes of media such as short cylinders, cubes, cones, or irregular shapes have been used for grinding work but today the nearly true spherical shape is predominant and has been found to provide the most economic form.
In contrast to rod milling the grinding action results from point contact rather than line contact. Such point contacts take place between the balls and the shell liners, and between the individual balls themselves. The material at those points of contact is ground to extremely fine sizes. The present day practice in ball milling is generally to reduce material to 35 mesh or finer. Grinding in a ball mill is not selective as it is in a rod mill and as a result more extreme fines and tramp oversize are produced.
Small Ball mills are generally recommended not only for single stage fine grinding but also have wide application in regrind work. The Small Ball millwith its low pulp level is especially adapted to single stage grinding as evidenced by hundreds of installations throughout the world. There are many applications in specialized industrial work for either continuous or batch grinding.
Wet grinding may be considered as the grinding of material in the presence of water or other liquids in sufficient quantity to produce a fluid pulp (generally 60% to 80% solids). Dry grinding on the other hand is carried out where moisture is restricted to a very limited amount (generally less than 5%). Most materials may be ground by use of either method in either ball mills or rod mills. Selection is determined by the condition of feed to the mill and the requirements of the ground product for subsequent treatment. When grinding dry some provision must be made to permit material to flow through the mill. Mills provide this necessary gradient from the point of feeding to point of discharge and thereby expedites flow.
The fineness to which material must be ground is determined by the individual material and the subsequent treatment of that ground material Where actual physical separation of constituent particles is to be realized grinding must be carried to the fineness where the individual components are separated. Some materials are liberated in coarse sizes whereas others are not liberated until extremely fine sizes are reached.
Occasionally a sufficient amount of valuable particles are liberated in coarser sizes to justify separate treatment at that grind. This treatment is usually followed by regrinding for further liberation. Where chemical treatment is involved, the reaction between a solid and a liquid, or a solid and a gas, will generally proceed more rapidly as the particle sizes are reduced. The point of most rapid and economical change would determine the fineness of grind required.
Laboratory examinations and grinding tests on specific materials should be conducted to determine not only the fineness of grind required, but also to indicate the size of commercial equipment to handle any specific problem.
lime ball mill - jxsc machine
The lime ball mill can superfinely grind lime or coal ash. The equipment consists of the main parts such as the feeding part, the discharging part, the turning part, and the transmission part (reducer, small transmission gear, motor, and electronic control). Simple and reasonable structure, reliable operation and large processing capacity. Lime is one of the main raw materials for concrete production, and its main function is to provide effective calcium oxide with cement, so that it can interact with certain ingredients in siliceous materials under hydrothermal conditions.
1. The lime ball mill adopts rolling bearings instead of sliding bearings, which greatly reduces friction, easy starting and significant energy saving; 2. It adopts a cone design at the discharge end. This not only increases the volume, but also forces the steel ball at the cone end to be classified. The closer it is to the exit, the smaller the diameter of the steel ball, which increases the effect of repeated grinding and the fineness of the material. 3. It uses the grooved ring-shaped liner, which increases the contact surface of the ball ore, strengthens the grinding effect, and has the ability to enhance the ore and reduce the power; 4. It adopts a whole frame, which is convenient for civil construction and equipment installation. The main uses of lime ball mills: Lime ball mills are used to grind a variety of ore and other materials. They are widely used in various sectors of the national economy such as beneficiation, construction and chemical industries.
The ball mill for lime is a horizontal cylindrical rotating device, driven by external gears, two bins, and a lattice ball mill. The material enters the first silo of the mill spirally through the feeding device through the hollow shaft of the feeding material. There is a stepped lining or a corrugated lining in the hopper, which contains steel balls of different specifications. The centrifugal force generated by the rotation of the cylinder brings the steel balls to a certain height After falling, it has a heavy impact and grinding effect on the material. After the material is coarsely ground in the first bin, it enters the second bin through a single-layer compartment board. This bin is inlaid with a flat liner and steel balls inside to further grind the material. The powder is discharged through the discharge grate plate to complete the grinding operation.
1. Ensure production capacity When selecting the model of limestone wet ball mill, it must be able to complete the required output under the condition that the required fineness of grinding is achieved, so as to achieve greater profit for the companys production;
2. Ability to leave adequate surplus When selecting the limestone wet ball mill model, we must consider the changes in the hardness and fineness of the ore. The selected limestone wet ball mill model can be used more widely to ensure the smooth commissioning of the equipment at the initial stage;
3. Due consideration is given to large equipment When selecting a limestone wet ball mill model, it is recommended that you properly consider large limestone wet ball mill models for three main reasons: First, large-scale equipment is the trend of recent industrial development; second, large-scale limestone wet ball mill equipment. The equipment is light in weight, occupies less land, has fewer production systems, fewer operators and auxiliary systems, and the corresponding investment and production costs are lower. Third, the large-scale limestone wet ball mill has good continuous operation and the unit production efficiency is smaller. The model of the limestone wet ball mill is higher.
As a professional large-scale ball mill equipment manufacturer, JXSC not only produces high-quality limestone wet ball mills, but also has a complete range of models. It is important that Hongxing is a local large-scale ball mill direct sales company in Henan, so in terms of the price of limestone wet ball mills Although the price of Red Star Limestone Wet Ball Mill may not be very low, under the premise of the same quality, the price of Red Star Limestone Wet Ball Mill is relatively favorable, so users and friends need not worry too much. If you want to know more about the details of the red star limestone wet ball mill and other equipment details, please feel free to consult.
industrial ball mills: steel ball mills and lined ball mills | orbis
Particle size reduction of materials in a ball mill with the presence of metallic balls or other media dates back to the late 1800s. The basic construction of a ball mill is a cylindrical container with journals at its axis. The cylinder is filled with grinding media (ceramic or metallic balls or rods), the product to be ground is added and the cylinder is put into rotation via an external drive causing the media to roll, slide and cascade. Lifting baffles are supplied to prevent the outer layer of media to simply roll around the cylinder.
Mill cylinders are typically supplied with a cooling jacket on their cylindrical portion for temperature control, especially when processing temperature-sensitive materials. For extreme temperatures, the ends of the cylinder can also be furnished with cooling apparatus.
ball mill, ball grinding mill - all industrial manufacturers - videos
... LN2 feeding systems, jar and ball sizes, adapter racks, materials
clearly structured user interface, memory for 9 SOPs
programmable cooling and grinding cycles (10 ...
The XRD-Mill McCrone was specially developed for the preparation of samples for subsequent X-ray diffraction (XRD). The mill is used for applications in geology, chemistry, mineralogy and materials science, ...
The Planetary Ball Mill PM 200, engineered by Retsch, is a milling device best suited for mixing and size reduction processes and is also capable of meeting the necessary requirements for colloidal grinding ...
... Micro Mill PULVERISETTE 0 is the ideal laboratory mill for fine comminution of medium-hard, brittle, moist or temperature-sensitive samples dry or in suspension as well as for homogenising of emulsions ...
... , fast, effective.
Impact and friction
The FRITSCH Mini-Mill PULVERISETTE 23 grinds the sample through impact and friction between grinding balls and the inside wall of the grinding ...
... grinding mills includes being safe throughout. When the mills are quoted we make sure to include any and all safety components needed.
Long life and minimum maintenance
To help you get the most of your ...
Annular gap and agitator bead mills are used for processing suspensions and highly viscous products in chemicals and cosmetics as well as in the food sector. Studies have shown that annular gap bead ...
... Pneumatic extraction from the surface of the agitated media bed
Separation of suspension from the agitated media by ball retaining device
Through careful selection of the size and quantity ...
Agitating power: 0,37 kW
Total Power Consumption : 1.44 kW
Total Weight : 100 kg
Metal Ball Size : 6.35 mm
Metal Ball Amount : 7 kg
Cold water consumption : 10 liters / hour ...
Cement Ball Mill
Processing ability: - 200 t/h
Max feeding size: - 25 mm
Product Fineness: - 0.074-0.89mm
Range of application: - limestone, calcium carbonate, clay, dolomite and other minerals ...
... grinds and classifies a product. Vilitek MBL-NK-80 mill is specially designed for grinding valuable materials, which, when grinding, the re-milled fractions are not a commodity product. In particular, this mill ...
Height: 1530 mm
Width: 650 mm
Length : 1025 mm
Ball mills are capable of rapidly producing chocolate, nut pastes (for gianduia), and spreadable creams.
It has been ...
mining equipment for sale - jxsc mining
JXSC Mine Machinery Factory (aka. JXSC Mining) provides a variety of mining equipment and mineral processing equipmentfor sale. Our equipment not only applied in large mining plants but also suitable for small scale metallurgy operations operated by small miners. whether you are making big business in the mineral industry or a small one, even you are just a hobbyist miner or mining fanatics, JXSC Mining can provide the best suitable mining machine for you.
The development of mineral processing equipment and mineral processing technology is synchronized, the mining process is dominant, and the equipment is the foundation. The birth of a new type of mineral processing equipment often leads to changes in the beneficiation process. The technical level of the equipment is not only the premise of the process level but also directly affects the smooth flow and application of the production process. The advancement of science and technology, the mutual penetration of various scientific categories and the integration of various industries, new structures, new materials, new technologies and new processing technologies emerge one after another. The extensive application of mechatronics and automatic control technology has effectively promoted beneficiation. Continuous innovation of equipment and development towards energy efficiency.
Mineral processing equipment includes: ball mill, crusher, pulverizer, jaw crusher, impact crusher, cone crusher, ultra-fine crusher, magnetic separator, dry magnetic separator, wet magnetic separator, double force ring height Gradient magnetic separator, magnetite ore dressing equipment, flotation machine, mining flotation machine, classifier, spiral classifier, sorghum spiral classifier, dryer, rotary kiln, shaker, hoist, high frequency Sieve, finished sieve, high-efficiency concentrator, spiral chute, disc granulator, trough feeder, energy-saving ball mill.
Mining Equipment Manufacturers, Our Main Products: Gold Trommel, Gold Wash Plant, Dense Media Separation System, CIP, CIL, Ball Mill, Trommel Scrubber, Shaker Table, Jig Concentrator, Spiral Separator, Slurry Pump, Trommel Screen.