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In all ore dressing and milling Operations, including flotation, cyanidation, gravity concentration, and amalgamation, the Working Principle is to crush and grind, often with rob mill & ball mills, the ore in order to liberate the minerals. In the chemical and process industries, grinding is an important step in preparing raw materials for subsequent treatment.In present day practice, ore is reduced to a size many times finer than can be obtained with crushers. Over a period of many years various fine grinding machines have been developed and used, but the ball mill has become standard due to its simplicity and low operating cost.
A ball millefficiently operated performs a wide variety of services. In small milling plants, where simplicity is most essential, it is not economical to use more than single stage crushing, because the Steel-Head Ball or Rod Mill will take up to 2 feed and grind it to the desired fineness. In larger plants where several stages of coarse and fine crushing are used, it is customary to crush from 1/2 to as fine as 8 mesh.
Many grinding circuits necessitate regrinding of concentrates or middling products to extremely fine sizes to liberate the closely associated minerals from each other. In these cases, the feed to the ball mill may be from 10 to 100 mesh or even finer.
Where the finished product does not have to be uniform, a ball mill may be operated in open circuit, but where the finished product must be uniform it is essential that the grinding mill be used in closed circuit with a screen, if a coarse product is desired, and with a classifier if a fine product is required. In most cases it is desirable to operate the grinding mill in closed circuit with a screen or classifier as higher efficiency and capacity are obtained. Often a mill using steel rods as the grinding medium is recommended, where the product must have the minimum amount of fines (rods give a more nearly uniform product).
Often a problem requires some study to determine the economic fineness to which a product can or should be ground. In this case the 911Equipment Company offers its complete testing service so that accurate grinding mill size may be determined.
Until recently many operators have believed that one particular type of grinding mill had greater efficiency and resulting capacity than some other type. However, it is now commonly agreed and accepted that the work done by any ballmill depends directly upon the power input; the maximum power input into any ball or rod mill depends upon weight of grinding charge, mill speed, and liner design.
The apparent difference in capacities between grinding mills (listed as being the same size) is due to the fact that there is no uniform method of designating the size of a mill, for example: a 5 x 5 Ball Mill has a working diameter of 5 inside the liners and has 20 per cent more capacity than all other ball mills designated as 5 x 5 where the shell is 5 inside diameter and the working diameter is only 48 with the liners in place.
Ball-Rod Mills, based on 4 liners and capacity varying as 2.6 power of mill diameter, on the 5 size give 20 per cent increased capacity; on the 4 size, 25 per cent; and on the 3 size, 28 per cent. This fact should be carefully kept in mind when determining the capacity of a Steel- Head Ball-Rod Mill, as this unit can carry a greater ball or rod charge and has potentially higher capacity in a given size when the full ball or rod charge is carried.
A mill shorter in length may be used if the grinding problem indicates a definite power input. This allows the alternative of greater capacity at a later date or a considerable saving in first cost with a shorter mill, if reserve capacity is not desired. The capacities of Ball-Rod Mills are considerably higher than many other types because the diameters are measured inside the liners.
The correct grinding mill depends so much upon the particular ore being treated and the product desired, that a mill must have maximum flexibility in length, type of grinding medium, type of discharge, and speed.With the Ball-Rod Mill it is possible to build this unit in exact accordance with your requirements, as illustrated.
To best serve your needs, the Trunnion can be furnished with small (standard), medium, or large diameter opening for each type of discharge. The sketch shows diagrammatic arrangements of the four different types of discharge for each size of trunnion opening, and peripheral discharge is described later.
Ball-Rod Mills of the grate discharge type are made by adding the improved type of grates to a standard Ball-Rod Mill. These grates are bolted to the discharge head in much the same manner as the standard headliners.
The grates are of alloy steel and are cast integral with the lifter bars which are essential to the efficient operation of this type of ball or rod mill. These lifter bars have a similar action to a pump:i. e., in lifting the product so as to discharge quickly through the mill trunnion.
These Discharge Grates also incorporate as an integral part, a liner between the lifters and steel head of the ball mill to prevent wear of the mill head. By combining these parts into a single casting, repairs and maintenance are greatly simplified. The center of the grate discharge end of this mill is open to permit adding of balls or for adding water to the mill through the discharge end.
Instead of being constructed of bars cast into a frame, Grates are cast entire and have cored holes which widen toward the outside of the mill similar to the taper in grizzly bars. The grate type discharge is illustrated.
The peripheral discharge type of Ball-Rod Mill is a modification of the grate type, and is recommended where a free gravity discharge is desired. It is particularly applicable when production of too many fine particles is detrimental and a quick pass through the mill is desired, and for dry grinding.
The drawings show the arrangement of the peripheral discharge. The discharge consists of openings in the shell into which bushings with holes of the desired size are inserted. On the outside of the mill, flanges are used to attach a stationary discharge hopper to prevent pulp splash or too much dust.
The mill may be operated either as a peripheral discharge or a combination or peripheral and trunnion discharge unit, depending on the desired operating conditions. If at any time the peripheral discharge is undesirable, plugs inserted into the bushings will convert the mill to a trunnion discharge type mill.
Unless otherwise specified, a hard iron liner is furnished. This liner is made of the best grade white iron and is most serviceable for the smaller size mills where large balls are not used. Hard iron liners have a much lower first cost.
Electric steel, although more expensive than hard iron, has advantage of minimum breakage and allows final wear to thinner section. Steel liners are recommended when the mills are for export or where the source of liner replacement is at a considerable distance.
Molychrome steel has longer wearing qualities and greater strength than hard iron. Breakage is not so apt to occur during shipment, and any size ball can be charged into a mill equipped with molychrome liners.
Manganese liners for Ball-Rod Mills are the world famous AMSCO Brand, and are the best obtainable. The first cost is the highest, but in most cases the cost per ton of ore ground is the lowest. These liners contain 12 to 14% manganese.
The feed and discharge trunnions are provided with cast iron or white iron throat liners. As these parts are not subjected to impact and must only withstand abrasion, alloys are not commonly used but can be supplied.
Gears for Ball-Rod Mills drives are furnished as standard on the discharge end of the mill where they are out of the way of the classifier return, scoop feeder, or original feed. Due to convertible type construction the mills can be furnished with gears on the feed end. Gear drives are available in two alternative combinations, which are:
All pinions are properly bored, key-seated, and pressed onto the steel countershaft, which is oversize and properly keyseated for the pinion and drive pulleys or sheaves. The countershaft operates on high grade, heavy duty, nickel babbitt bearings.
Any type of drive can be furnished for Ball-Rod Mills in accordance with your requirements. Belt drives are available with pulleys either plain or equipped with friction clutch. Various V- Rope combinations can also be supplied.
The most economical drive to use up to 50 H. P., is a high starting torque motor connected to the pinion shaft by means of a flat or V-Rope drive. For larger size motors the wound rotor (slip ring) is recommended due to its low current requirement in starting up the ball mill.
Should you be operating your own power plant or have D. C. current, please specify so that there will be no confusion as to motor characteristics. If switches are to be supplied, exact voltage to be used should be given.
Even though many ores require fine grinding for maximum recovery, most ores liberate a large percentage of the minerals during the first pass through the grinding unit. Thus, if the free minerals can be immediately removed from the ball mill classifier circuit, there is little chance for overgrinding.
This is actually what has happened wherever Mineral Jigs or Unit Flotation Cells have been installed in the ball mill classifier circuit. With the installation of one or both of these machines between the ball mill and classifier, as high as 70 per cent of the free gold and sulphide minerals can be immediately removed, thus reducing grinding costs and improving over-all recovery. The advantage of this method lies in the fact that heavy and usually valuable minerals, which otherwise would be ground finer because of their faster settling in the classifier and consequent return to the grinding mill, are removed from the circuit as soon as freed. This applies particularly to gold and lead ores.
Ball-Rod Mills have heavy rolled steel plate shells which are arc welded inside and outside to the steel heads or to rolled steel flanges, depending upon the type of mill. The double welding not only gives increased structural strength, but eliminates any possibility of leakage.
Where a single or double flanged shell is used, the faces are accurately machined and drilled to template to insure perfect fit and alignment with the holes in the head. These flanges are machined with male and female joints which take the shearing stresses off the bolts.
The Ball-Rod Mill Heads are oversize in section, heavily ribbed and are cast from electric furnace steel which has a strength of approximately four times that of cast iron. The head and trunnion bearings are designed to support a mill with length double its diameter. This extra strength, besides eliminating the possibility of head breakage or other structural failure (either while in transit or while in service), imparts to Ball-Rod Mills a flexibility heretofore lacking in grinding mills. Also, for instance, if you have a 5 x 5 mill, you can add another 5 shell length and thus get double the original capacity; or any length required up to a maximum of 12 total length.
On Type A mills the steel heads are double welded to the rolled steel shell. On type B and other flanged type mills the heads are machined with male and female joints to match the shell flanges, thus taking the shearing stresses from the heavy machine bolts which connect the shell flanges to the heads.
The manhole cover is protected from wear by heavy liners. An extended lip is provided for loosening the door with a crow-bar, and lifting handles are also provided. The manhole door is furnished with suitable gaskets to prevent leakage.
The mill trunnions are carried on heavy babbitt bearings which provide ample surface to insure low bearing pressure. If at any time the normal length is doubled to obtain increased capacity, these large trunnion bearings will easily support the additional load. Trunnion bearings are of the rigid type, as the perfect alignment of the trunnion surface on Ball-Rod Mills eliminates any need for the more expensive self-aligning type of bearing.
The cap on the upper half of the trunnion bearing is provided with a shroud which extends over the drip flange of the trunnion and effectively prevents the entrance of dirt or grit. The bearing has a large space for wool waste and lubricant and this is easily accessible through a large opening which is covered to prevent dirt from getting into the bearing.Ball and socket bearings can be furnished.
Scoop Feeders for Ball-Rod Mills are made in various radius sizes. Standard scoops are made of cast iron and for the 3 size a 13 or 19 feeder is supplied, for the 4 size a 30 or 36, for the 5 a 36 or 42, and for the 6 a 42 or 48 feeder. Welded steel scoop feeders can, however, be supplied in any radius.
The correct size of feeder depends upon the size of the classifier, and the smallest feeder should be used which will permit gravity flow for closed circuit grinding between classifier and the ball or rod mill. All feeders are built with a removable wearing lip which can be easily replaced and are designed to give minimum scoop wear.
A combination drum and scoop feeder can be supplied if necessary. This feeder is made of heavy steel plate and strongly welded. These drum-scoop feeders are available in the same sizes as the cast iron feeders but can be built in any radius. Scoop liners can be furnished.
The trunnions on Ball-Rod Mills are flanged and carefully machined so that scoops are held in place by large machine bolts and not cap screws or stud bolts. The feed trunnion flange is machined with a shoulder for insuring a proper fit for the feed scoop, and the weight of the scoop is carried on this shoulder so that all strain is removed from the bolts which hold the scoop.
High carbon steel rods are recommended, hot rolled, hot sawed or sheared, to a length of 2 less than actual length of mill taken inside the liners. The initial rod charge is generally a mixture ranging from 1.5 to 3 in diameter. During operation, rod make-up is generally the maximum size. The weights per lineal foot of rods of various diameters are approximately: 1.5 to 6 lbs.; 2-10.7 lbs.; 2.5-16.7 lbs.; and 3-24 lbs.
Forged from the best high carbon manganese steel, they are of the finest quality which can be produced and give long, satisfactory service. Data on ball charges for Ball-Rod Mills are listed in Table 5. Further information regarding grinding balls is included in Table 6.
Rod Mills has a very define and narrow discharge product size range. Feeding a Rod Mill finer rocks will greatly impact its tonnage while not significantly affect its discharge product sizes. The 3.5 diameter rod of a mill, can only grind so fine.
Crushers are well understood by most. Rod and Ball Mills not so much however as their size reduction actions are hidden in the tube (mill). As for Rod Mills, the image above best expresses what is going on inside. As rocks is feed into the mill, they are crushed (pinched) by the weight of its 3.5 x 16 rods at one end while the smaller particles migrate towards the discharge end and get slightly abraded (as in a Ball Mill) on the way there.
We haveSmall Ball Mills for sale coming in at very good prices. These ball mills are relatively small, bearing mounted on a steel frame. All ball mills are sold with motor, gears, steel liners and optional grinding media charge/load.
Ball Mills or Rod Mills in a complete range of sizes up to 10 diameter x20 long, offer features of operation and convertibility to meet your exactneeds. They may be used for pulverizing and either wet or dry grindingsystems. Mills are available in both light-duty and heavy-duty constructionto meet your specific requirements.
All Mills feature electric cast steel heads and heavy rolled steelplate shells. Self-aligning main trunnion bearings on large mills are sealedand internally flood-lubricated. Replaceable mill trunnions. Pinion shaftbearings are self-aligning, roller bearing type, enclosed in dust-tightcarrier. Adjustable, single-unit soleplate under trunnion and drive pinionsfor perfect, permanent gear alignment.
Ball Mills can be supplied with either ceramic or rubber linings for wet or dry grinding, for continuous or batch type operation, in sizes from 15 x 21 to 8 x 12. High density ceramic linings of uniform hardness male possible thinner linings and greater and more effective grinding volume. Mills are shipped with liners installed.
Complete laboratory testing service, mill and air classifier engineering and proven equipment make possible a single source for your complete dry-grinding mill installation. Units available with air swept design and centrifugal classifiers or with elevators and mechanical type air classifiers. All sizes and capacities of units. Laboratory-size air classifier also available.
A special purpose batch mill designed especially for grinding and mixing involving acids and corrosive materials. No corners mean easy cleaning and choice of rubber or ceramic linings make it corrosion resistant. Shape of mill and ball segregation gives preferential grinding action for grinding and mixing of pigments and catalysts. Made in 2, 3 and 4 diameter grinding drums.
Nowadays grinding mills are almost extensively used for comminution of materials ranging from 5 mm to 40 mm (3/161 5/8) down to varying product sizes. They have vast applications within different branches of industry such as for example the ore dressing, cement, lime, porcelain and chemical industries and can be designed for continuous as well as batch grinding.
Ball mills can be used for coarse grinding as described for the rod mill. They will, however, in that application produce more fines and tramp oversize and will in any case necessitate installation of effective classification.If finer grinding is wanted two or three stage grinding is advisable as for instant primary rod mill with 75100 mm (34) rods, secondary ball mill with 2540 mm(11) balls and possibly tertiary ball mill with 20 mm () balls or cylpebs.To obtain a close size distribution in the fine range the specific surface of the grinding media should be as high as possible. Thus as small balls as possible should be used in each stage.
The principal field of rod mill usage is the preparation of products in the 5 mm0.4 mm (4 mesh to 35 mesh) range. It may sometimes be recommended also for finer grinding. Within these limits a rod mill is usually superior to and more efficient than a ball mill. The basic principle for rod grinding is reduction by line contact between rods extending the full length of the mill, resulting in selective grinding carried out on the largest particle sizes. This results in a minimum production of extreme fines or slimes and more effective grinding work as compared with a ball mill. One stage rod mill grinding is therefore suitable for preparation of feed to gravimetric ore dressing methods, certain flotation processes with slime problems and magnetic cobbing. Rod mills are frequently used as primary mills to produce suitable feed to the second grinding stage. Rod mills have usually a length/diameter ratio of at least 1.4.
Tube mills are in principle to be considered as ball mills, the basic difference being that the length/diameter ratio is greater (35). They are commonly used for surface cleaning or scrubbing action and fine grinding in open circuit.
In some cases it is suitable to use screened fractions of the material as grinding media. Such mills are usually called pebble mills, but the working principle is the same as for ball mills. As the power input is approximately directly proportional to the volume weight of the grinding media, the power input for pebble mills is correspondingly smaller than for a ball mill.
A dry process requires usually dry grinding. If the feed is wet and sticky, it is often necessary to lower the moisture content below 1 %. Grinding in front of wet processes can be done wet or dry. In dry grinding the energy consumption is higher, but the wear of linings and charge is less than for wet grinding, especially when treating highly abrasive and corrosive material. When comparing the economy of wet and dry grinding, the different costs for the entire process must be considered.
An increase in the mill speed will give a directly proportional increase in mill power but there seems to be a square proportional increase in the wear. Rod mills generally operate within the range of 6075 % of critical speed in order to avoid excessive wear and tangled rods. Ball and pebble mills are usually operated at 7085 % of critical speed. For dry grinding the speed is usually somewhat lower.
The mill lining can be made of rubber or different types of steel (manganese or Ni-hard) with liner types according to the customers requirements. For special applications we can also supply porcelain, basalt and other linings.
The mill power is approximately directly proportional to the charge volume within the normal range. When calculating a mill 40 % charge volume is generally used. In pebble and ball mills quite often charge volumes close to 50 % are used. In a pebble mill the pebble consumption ranges from 315 % and the charge has to be controlled automatically to maintain uniform power consumption.
In all cases the net energy consumption per ton (kWh/ton) must be known either from previous experience or laboratory tests before mill size can be determined. The required mill net power P kW ( = ton/hX kWh/ton) is obtained from
Trunnions of S.G. iron or steel castings with machined flange and bearing seat incl. device for dismantling the bearings. For smaller mills the heads and trunnions are sometimes made in grey cast iron.
The mills can be used either for dry or wet, rod or ball grinding. By using a separate attachment the discharge end can be changed so that the mills can be used for peripheral instead of overflow discharge.
Ball mill is a major equipment in the production of power plants, cement plants, mines, chemical industry, metallurgy and other industries, the liner is one of the components of the mill, the main role is to protect the cylinder, the cylinder from the grinding body and Material direct impact and friction, help to improve the mill grinding efficiency, increase production and reduce metal consumption. As the liner in the harsh conditions of long-term conditions, maintenance and replacement of considerable volume, not only requires human, material and financial resources, but also a direct impact on productivity.
Ball mill liner plays a major role in protecting the inner wall of the anchor windlass. Different shapes of the ball mill lining plate can improve the grinding effect of the ball mill and improve the working efficiency of the ball mill. 1, flat ball mill liner, the surface smooth, suitable for installation in the fine grinding warehouse. 2, the pressure of the type of ball mill liner, suitable for coarse grinding warehouse, for low speed ball mill. 3, ladder-type ball mill liner, ladder liner is better than the pressure liner, suitable for installation in the coarse grinding warehouse. 4, small corrugated liner crest and pitch are small, suitable for fine grinding and coal mill. 5, end cover liner installed in the grinding head cover or cylinder cover to protect the end cover from wear and tear. 6, ring groove liner in the lining of the T surface for casting a circular groove, after installation to form a circular groove, suitable for multi-warehouse grinding of the first and second positions, dry, wet grinding Machine can be. 7, grading liner, grinding mill for the ideal state should be large particles of material with a large diameter grinding body to impact and crush, that is, in the direction of the mill feed with large diameter grinding body, with the material The direction of the material to the gradual reduction of the grinding body should be sequentially reduced.
Qiming Casting is one of the largest manganese steel, chromium steel, and alloy steel foundry in China. Products include crusher wear parts, Crusher spare parts, mill liners, shredder wear parts, apron feeder pans, and electric rope shovel parts.
According to its manufacturing process, PCBN is divided into CBN directly combined into a sintered block through high temperature and high pressure, or sintered at high temperature and high pressure with a binder such as metal or ceramics; according to the final composite method, there are separate CBN sintered blocks and CBN / PCBN composite sintered hard alloy composite sheet. This article will focus on the cutting performance of PCBN composite chip tools.
The crystal structure of CBN is similar to that of diamond, with the same chemical bond types and similar lattice constants, so it has similar hardness and strength to diamond. The microhardness of CBN powder is HV80009000, and the hardness of the sintered PCBN is generally HV30005000.
CBN is extremely chemically inert. It does not chemically react with iron-based materials at 1200-1300C, and only reacts with carbon at 2000C; it is stable to acids and alkalis in neutral and reducing gases. Its bonding and diffusion effect on various materials is much smaller than that of cemented carbide
Among all kinds of tool materials, the thermal conductivity of CBN is second only to diamond, which is much higher than that of cemented carbide, and as the temperature rises, the thermal conductivity of PCBN increases.
When PCBN tools cut hardened steel, as the hardness of the processed material increases, the tool life is not monotonously decreased, but the tool life is the lowest at HRC40 (as shown in Figure 1), Figure 1VB=0.2mm; ap=0.5mm ; F=0.1mm/r, workpiece material: 35CrMo. When the hardness of the workpiece material is higher than this hardness, the tool life will increase instead. This is mainly due to the low hardness loss of PCBN material at high temperature, and when the workpiece material has a high hardness, the metal in the cutting area will be softened due to the cutting heat, which makes the cutting process easier. The characteristic of PCBN is very suitable for processing high-hardness materials. Turning instead of grinding can obtain the surface quality that can only be obtained by grinding.
When cutting normalized materials, the life of PCBN tools is lower than that of cemented carbide tools (as shown in Figure 2), the cutting amount: f=0.1mm/r; ap=0.5mm. And the tool life is lower than when cutting hardened steel. It can be seen that PCBN tools are not suitable for processing normalized materials.
The relationship between the tool life and cutting speed of cutting gray cast iron PCBN does not conform to Taylor's formula. The flank wear VB and rake face crescent wear depth KT both show the same law (as shown in Figure 3). Figure 3 Cutting Dosage: f=0.1mm/r, ap=0.5mm.
When cutting non-ferrous metals, sintered diamond (PCD) is usually the best tool material, but when cutting wear-resistant brass, PCBN tool life is higher than that of sintered diamond and cemented carbide tools (as shown in Figure 4). Figure 4 Cutting consumption: v=200m/min; f=0.2mm/r, ap=1.0mm.
As shown in Figure 5, cutting parameters: f=0.05mm/r, ap=0.05mm; workpiece material: HPM31HRC57; ball end mill R5 down milling Figure 5 shows the relationship between the tool flank wear and the cutting distance when PCBN tools cut hardened steel at different speeds. It can be seen from Figure 5: when the cutting speed exceeds a certain limit, the higher the cutting speed, the higher the tool wear speed On the contrary, it is reduced, that is, the life of PCBN tools at high speeds is higher than that at low speeds, so PCBN tools are suitable for high-speed cutting of high-hardness materials.
As shown in Figure 6, the workpiece material is cast iron, which is a comparison of the tool life of PCBN tools under dry and wet cutting conditions. It can be seen from Figure 6 that in the case of dry cutting, the life of the PCBN tool is actually higher than that of the cutting fluid. The main reason is that the cutting temperature is high during dry cutting, and the high temperature hardness of PCBN is high, so the hardness loss is less, and the workpiece material The hardness loss is large at high temperature, and it is easier to cut after the hardness is reduced.
Different materials can be processed with PCBN tools to obtain lower surface roughness. Figure 7 shows the comparison of the surface roughness of PCBN tools and cemented carbide tools when processing cast iron. It can be seen from Figure 7 that the surface roughness of PCBN tools is much better than that of carbide tools, and with the increase of cutting speed, it is getting closer and closer to the theoretical value of roughness. In addition, due to the high hardness and wear resistance of PCBN tools, a more consistent surface roughness can be obtained in a long time. Figure 7 Workpiece material: cast iron FC25; cutting amount: f=0.1mm/r; ap=0.3mm.
As shown in Figure 8, the machined surface obtained by grinding usually produces tensile stress. When hardened steel is processed with PCBN tools, the surface structure of the workpiece usually has residual compressive stress, which can improve the fatigue strength and wear resistance of the part. Figure 8 Cutting conditions: workpiece material: GCr15 quenching; grinding: v=35m/s; vf=10mm/min; fr=0.008mm; turning: v=70m/min, f=0.07mm/r; ap=0.1mm .
The comparison between the surface hardness of PCBN tool cutting hardened steel and the grinding is shown in Figure 9. It can be seen from Figure 9 that the surface hardness of the workpiece obtained by grinding has decreased, while the hardness of the machined surface obtained by PCBN tool processing has increased slightly, which improves the mechanical properties of the machined surface. Fig. 9 Workpiece material: SCM21, quenched HRC50; cutting amount: turning: v=300m/min; f=0.3mm/r; ap=1.0mm; grinding: vc=1450m/min; vw=80m/min; ap= 0.015mm. In addition, when the PCBN tool cuts hard materials, the cutting heat generated by the tool's good thermal conductivity is taken away by the chips, and the surface fiber structure of the workpiece surface does not change significantly. If the cutting amount is not selected properly, the surface is easy to produce burn.
PCBN cutting tools have better cutting performance than other material cutting tools, especially suitable for the cutting of high-hardness hardened steel and wear-resistant materials. It has excellent cutting performance in high-speed cutting and dry cutting. It can be used under certain conditions. The machining surface quality is comparable to that of grinding; however, PCBN tool life has a special change rule, such as: low tool life when cutting medium-hardened hardened steel and normalized steel, bending of the tool life curve when cutting cast iron, etc. Understand and master these special laws, you can give full play to its superior cutting performance in use, and create huge economic benefits.
Ball Mill The ball mill has been around for eons. There are many shapes and sizes and types. There is a single enclosed drum-type where material is placed in the drum along with a charge of grinding media. These can be in various shapes, and typically they are balls. There is a whole science in the size of the starting material versus the ball size, shape material of construction and charge percentage of grinding media. All of these variables affect particle size, shape, and grinding efficiency. This type of grinding is very good for abrasive materials to prevent contamination. The grinding media as well as the interior surfaces of the mill can be lined with abrasion resistant materials suited to the material being ground. In some cases, it can even be the material being ground. However, the batch type system is not a very efficient means of grinding. There is a variety of ball mill that is a continuous process versus a batch process. It has an external classifier which returns the oversized material to the ball mill for further milling. This system is much more efficient in the grinding ability, but it is much more difficult to line the entire system with wear parts to grind an abrasive material.
Ball mill grinding is one method of crushing ore to an appropriate size fraction.Specifically, ore is put into a large receptacle (a drum) and then it rotates slowly around.Inside the receptacle, there are balls, usually made of metal, that as the ore is rotated around the revolving drum the ore is crushed as the balls rise and fall.The drum has a slight tilt to it, from one end to the other so that the ore slowly works its way to discharging end.The trick or art to all of this is to rotate the drum at a distinct rpm and the balls are harder than the ore so as to efficiently crush the continuous stream of ore to the desired size at the discharge end.
The ball mill is a key piece of equipment for grinding crushed materials, and it is widely used in production lines for powders such as cement, silicates, refractory material, fertilizer, glass ceramics, etc. as well as for ore dressing of both ferrous and non-ferrous metals. The ball mill can grind various ores and other materials either wet or dry. There are two kinds of ball mill, grate type and overfall type due to different ways of discharging material. There are many types of grinding media suitable for use in a ball mill, each material having its own specific properties and advantages. Key properties of grinding media are size, density, hardness, and composition.
The grinding chamber can also be filled with an inertshield gasthat does not react with the material being ground, to prevent oxidation or explosive reactions that could occur with ambient air inside the mill.
China manufacturing industries are full of strong and consistent exporters. We are here to bring together China factories that supply manufacturing systems and machinery that are used by processing industries including but not limited to: ball mill liner, mill liner, ball mill. Here we are going to show you some of the process equipments for sale that featured by our reliable suppliers and manufacturers, such as Ball Mill Parts Liner. We will do everything we can just to keep every buyer updated with this highly competitive industry & factory and its latest trends. Whether you are for group or individual sourcing, we will provide you with the latest technology and the comprehensive data of Chinese suppliers like Ball Mill Parts Liner factory list to enhance your sourcing performance in the business line of manufacturing & processing machinery.
Leading supplier of high alloy castings and forgings. There are 4 companies with sales of more than 100 million yuan, across the 4 major areas of wear resistance, heat resistance, corrosion resistance, and machinery
Ball Mill liners are an extremely efficient variant of mill liners, which is what compels the ball mill liners manufacturers to manufacture them in the first place. If used properly, they may last pretty long. However, at one point or another, we may be obligated to replace the ball liners mill, due for various reasons.
Before installing a ball mill liner initially, we need to understand its working. In other words, we need to understand how long it will work, and if it works efficiently. Furthermore, judging the cost will also be a reasonable thing to do. The culmination of this will lead us to a clearer understanding of how and when to do the replacement job, which will help us make a timely schedule.
In order to ensure efficiency and coordination during the replacement process, we will be needing expert supervision over the process, and laborers and technicians that very well understand the process. If this is not ensured, the replacement procedure will not go smoothly and as a consequence, we may also have an improper replacement.
For efficient and proper removal, you must first clean the mill. You may have pulp accumulated on the ball mill that you need to clean. Furthermore, remove the rubber pad, clean the wall and remove the dust by descaling the cylinder. Once the barrel is fixed, ensure good ventilation so that the replacement process can start.
First, remove the lining screws, then remove the line of the ball by line. It should be ensured that necessary safety precautions are taken because this is the point where the injury is most common to occur. When lifting the ball out, make sure to keep the wire rope and hook into consideration, that they are firmly at their place. Hoisting should also be done carefully.
We have to install the new balls keeping the gaps and time periods into consideration. The spiral on the ball mill liner should be fixed, and the seal and gasket shall be applied carefully, ensuring that there are no leakages. The inner cylinder should be screwed tightly and it should be cemented properly so that it can solidify and culminate the reinstallation process.
The mill liner should be revisited to ensure that all the things had been done properly, and no people or tools were left behind. If so, it can cause a lot of problems and damages, especially the loss of human lives.
The process of replacing these ball liners is very easy but needs to be handled with real care. You can get in touch with Qiming Machinery if you are looking to get any information about Ball Mill liners.
Qiming Machinery is the leading manganese steel, chromium steel, alloy steel, and heat-resisting steel manufacturer in China. We manufacture crusher wear parts, shredder wear parts, mill liners, apron feeder pans, and other wear parts for customers.
Manganese steel is a kind of material for When it comes to manganese mill liners, Qiming Casting is one of the largest austenitic manganese steel cast foundries in China. With over 20 years of cast technology, Our austenitic manganese steel mill liners span life more than other foundries.
The hardness of manganese steel in the solution annealed and water quenched condition is normally around 220 HB. It is possible to strain to harden this material to approximately 500 HB. In order to achieve this high hardness level, the impact loading must be high while the material wearing away from gouging abrasion is limited. It is typical in crushing applications where the main wear mechanism is gouging abrasion that the manganese steel will harden to some intermediate level, typically 350-450 HB.
This material used for grid liners, and generally smaller mills. Its great advantage is that it works hardens under stress, yet the substrate remains tough and can withstand extreme impact without fracture. Its primary disadvantage is that it spreads with impact, so solid liners begin to squeeze together and become extremely difficult to remove, and can damage a mill shell if the stress is allowed to build up to an extreme level.
Qiming Casting is one of the largest manganese steel, chromium steel, and alloy steel foundry in China. Products include crusher wear parts, Crusher spare parts, mill liners, shredder wear parts, apron feeder pans, and electric rope shovel parts.
When it comes to Replacement hammer mill wear parts, Qiming Casting has been crushing the market for decades. If you demand the peace of mind that comes with ISO 9001-certified, fully-guaranteed and warranted replacement parts for your hammer mill.
High manganese steel hammer ensures the highest possible wear life is combined with mechanical reliability and numerous mounting possibilities. Thanks to the accurately balanced structure, the Qiming Casting manganese steel hammer is easy and economical to install.
As a high manganese steel grade, it offers excellent work hardening properties. High manganese steel plate becomes increasingly hard when the surfaces of components are subject to repeated impact or abrasion. Its toughness, derived from high tensile strength and ductility, enables shock leads to be absorbed safely. Lack of lubrication or the intrusion of grit or sand particles does not seriously impair the wearing surfaces of components in contact. These characteristics combine to make high manganese steel plate an ideal steel for use as wearing plates in those situations where abrasion, impact, or lubrication difficulties are encountered. The steel has the unique property in service of rapidly developing a work hardened surface whilst retaining its tough interior.
30CrNiMo Low Alloy Steel hammers provide longer life and often better value for operations that dont run a steady diet of autos and heavier scrap that work hardens manganese hammers. Our 30CrNiMo Low Alloy Steel hammers offer hardness at the working end and less hardness around the hammers pinhole. The compromise provides for less wear on hammer pins. By using this material, the shredder hammer can get different hardness: The bar of shredder hammers hardness around: 35-40 HRC, The working area of shredder hammers hardness around 45-55 HRC.
This new type high manganese steel crusher hammer withtic cermet rodis a good substitute for high chromium cast iron complex crusher hammer. It solves the problem of easy to be broken with high hardness in high chromium crusher hammer, furthermore, the wear life could be increased -up to 3 times, delivering fewer change-outs, more uptime, and lower maintenance costs.
Qiming Casting is one of the largest manganese steel, chromium steel, and alloy steel foundry in China. Products include crusher wear parts, Crusher spare parts, mill liners, shredder wear parts, apron feeder pans, and electric rope shovel parts.Get in Touch with Mechanic