mill liners for ball mill

ball mill liner design

There are many different designs and styles of ball mill liners. As with grinding balls local economics and ultimately operating costs determine the best design and material to use. The initial set of liners is rarely the final design selected. Based upon individual experience, mill superintendents develop preferences for liner designs. The following is given as a guideline for the initial set of liners.

For 60 mm (2.5) and smaller top size balls for cast metal liners use double wave liners with the number of lifters to the circle approximately 13.1 D in meters (for D in feet, divide 13.1 D by 3.3). Wave height above the liners from1.5 to 2 times the liner thickness. Rubber liners of the integral molded design follow the cast metal design. If using the replaceable lifter bar design in either metal or rubber the number of lifters should be about 3.3 D in meters (for D in feet* divide 3.3 D by 3.3) with the lifter height above the liners about twice the liner thickness. The use of double wave liners, particularly when using 50 mm (2) or larger balls, may show a loss of 5% or so in the mill power draw until the waves wear in and the balls cannest between the lifters.

When liners, and double wave liners in particular, wear with circumferential grooves, slipping of the charge is indicated, and this warns of accelerated wear. When the top size ball is smaller than 50mm (2.5) and mill speed is less than 72% of critical wear resistant cast irons can be used. For other conditions alloyed cast steel is recommended.Rubber liners are well suited to this same area and not onlyreduce operating costs but can reduce noise levels.

Single wave liners are recommended for larger size balls (50mm/2.5 and larger). The number of the lifters to the circle equals approximately 6.6 D in meters (for D in feet, divide 6.6 D by 3.3). The liners are from 50 to 65 mm thick (2 to 2.5) with the waves from 60 to 75 mm (2.5 to 3) above the liners. The replaceable lifter bar design madeof either metal or rubber in about the same design proportions can be used. There could be a loss in power with rubber particularly if the mill speed is faster than about 72% of critical speed, and the ball size is larger than 75 mm. Because of the impacting from the large balls, single wave liners for ball mills are usually made from alloyed steels or special wear-resistant alloyed cast irons. Because of the difficulty of balancing growth and wear with work hardening manganese steel is used infrequently and then with extreme care to allow for growth.

When a grate discharge is used the grates and wear platesare normally perpendicular to the mill axis while the discharge pans conform to the slope of the mill head. The grates and wear plates are normally made from alloy wear resistant cast steel or rubber. They are ribbed to prevent racing and excessive wear. The dischargers and pans are generally made from either wear resistant cast ironor rubber, or wear resistant fabricated steel.Slot plugging can be a problem in grate discharge mills. Whether the grates are made of metal or rubber the slots should have ample relief tapered toward the discharge side. Total angles 7 to 10 degrees (3.5 to 5 degrees per side) are commonly used. Metal grates often havea small lead-in pocket or recess which can fill in with peened metal rather than have the slot peen shut. With the proper combination of metal internals and rubber surfaces, rubber grates have flexibility that tend to make them self cleaning and yet not fail due to flexing.

Except when using rubber liners, the mill surfaces are covered with a protective rubber or plastic material toprotect the surfaces from pulp racing and corrosion. This is done in wet grinding mills. Since dry grinding mills get hot due to heat from grinding generally rubber liners and rubber materials cannot be used.

Shell liners may be furnished of various materials and of several designs. In each case the material used is the best obtainable, resulting in the lowest cost per ton of ore ground. The liner contours are selected for the specific grinding application and take into consideration liner wear, scrap loss, and mill capacity.

Liners cast of Manganese Steel, Ni-Hard, Chrome-moly, or other similar materials may be of the step type, block type, wave type, or the two-piece plate and lifter construction. These are illustrated on the right. During the past years of building ball Mills various other shapes of liners have been tried, such as the pocket type, spiral liners, etc.; in most cases it is found that these special shapes and designs are not justifiable from the standpoint of economics. They involve additional costs which are not generally recovered from an increased efficiency in milling operation.

Lorain Shell Liners consist of high carbon rolled steel plates accurately formed to the mill shell radius. These are held in place by rolled alloy steel heat treated lift bars. This type liner is carefully engineered for the specific grinding application. Variations in lift bar design and liner plate thickness provide this flexibility of design for application.

All shell liners designed for ball mill operations are of such size and shape that they will easily pass through the manhole opening to facilitate relining operations. In rod mill work the design is such that they will easily pass through the large ball open end discharge trunnion.

Where cast liners are used, and especially in rod mill applications, we furnish rubber shell liner backing to help cushion the impact effect of the media within the mill and prevent pulp racing. With the Lorain type of liner such shell liner backing is not required. For special applications where severe corrosive conditions exist a shell liner of special alloys can be furnished and also the interior surface of the shell can be treated to protect such parts from the corrosive conditions.

Head liners are of the segmental type constructed of Manganese Steel, Chrome molybdenum, or Ni-Hard and are designed to pass easily through the manhole opening or discharge opening in the case of rod mills. For ball mill work ribs are cast with the feed head liners to deflect the ball mass and minimize wear on the headliner itself.

Where cast liners are used shell liner bolts and head liner bolts are made of forged steel with an oval head to prevent turning and loosening within the liners. These are held in place with two hex nuts and a cut washer. For wet grinding applications special waterproof washers can be furnished.

Theeffect of liner design upon mill performance appears to have received little attention. Clearly, the main function of the liner is to form a removable surface to the null body, which may be replaced when seriously worn.

It is also clear however, that the metal plates which serve this purpose may have a surface which ranges from smooth in one which carries an intricate pattern of raised bars or sunken depressions. The merits of the various types do not appear, however, to have been studied.

where smooth liners are those which have projections insufficient to give appreciable keying between the liner and the ball charge, whilst lifter liners are those which are so heavily ribbed as to give rise to appreciable interlocking between the balls and the liners.

Various common types of liners are illustrated in Fig. 6.12. Although these liners have various patterns of projections, or depressions, to give an amount of interaction between the liner and the grinding medium, it would be expected that wear would round the edges. It is doubtful whether, after some time in service, the performance of a mill with these liners differs appreciably from that of a mill with a smooth surface. Liners furnished with heavy lifter bars are also sometimes used and in such a case the locking of the ball charge to the shell must be very effective. Nevertheless, although a few vague general statements to the effect that a lifter mill gives a product with different size characteristics to that of a smooth mill have appeared, the point does not appear to have been widely investigated. It is probable, however, that, on the grounds of differences in the size characteristics of the products, there exists no sound reason for the use of lifters in preference to the normal smooth liners.

It is possible that, when a material with a low coefficient of friction is milled, the charge might slip on a smooth mill shell, with consequent loss of grinding capacity, and in such a case the use of lifter bars might well be the solution. It has also been suggested by one of the authors, Rose, that the use of lifter bars might eliminate the surging of the charge sometimes encountered in mill operation.

An entirely different conception of the duty of the mill liner underlies the design of the studded liner developed by Usines Emile Henricot of Count St. Etienne. These liners, illustrated in Fig. 6.12 and Fig. 6.13, consist of comparatively thin plate liners with uniformly spaced studs on the working surface; these studs being integral with the plate. Provided the spaces between the studs are not allowed to become choked with tramp-iron, etc., the studs furnish a good key between the shell and the charge which, it is claimed, leads to a greater power consumption and to improved grinding. Furthermore it would appear that the studs impose a definite geometrical arrangement in the outer layer of balls which, in turn, brings about a closer packing, throughout the ball mass, than obtains with conventional types of liner. This effect would also lead to improved performance. Evidence of this effect of the studs upon the packing of the charge appears in Fig. 6.13b, for the balls are clearly seen to lie in rows in the mill instead of in completely random array.

An incidental merit claimed for these liners is that the high bearing pressure between the balls and the studs of the liners leads to work hardening of the studs; with a consequential reduction of the rate of metal wear.

The Henricot liners, which have been discussed in a paper by Belwinkel, appear to be the only attempt so far made to influence the grinding characteristics of a mill by means of correctly designed liners. It would therefore appear that there is some room for development in this direction.

metallic mill liners - metso outotec

Metso metallic mill linings are produced at our own foundries. Our chromium molybdenum steel and high-chromium white irons are specially developed for mill lining applications and are carefully selected based on the operating conditions of each mill. Our foundries apply strict quality assurance programs at every phase of research, development, design and production. This ensures high, uniform quality for the entire supply. Precise dimensions and close tolerances guarantee that your mill lining has a perfect fit.

Metso metallic mill linings are always designed with one thing in mind: to maximize performance and minimize replacement time. The solution offers total freedom of design and the possibility to optimize your lining based on operating data and liner handler capacity. Using linings of a modern design and maximized size minimizes the number of liners needed and thereby your downtime.

Metso offers mill linings with materials and designs optimized for each specific application. We work closely with our customers and carefully follow their process to make sure the lining we supply is always optimized for current operating conditions. We can design and supply mill linings for all types of mills - for Metso mills as well as for competitor mills - and for all parts in the mill. Our wide product range, innovations, knowledge and experience make us unique. Our approach to lining design is focused on grinding performance, mill uptime and safety.

More than a liningWhen buying a mill lining from Metso you get more than just a wear part. We always do a pre-study and design the lining based on your conditions and targets. Wear and performance monitoring are regularly done to better understand your grinding process and to optimize the lining accordingly. Technical support is offered, and we arrange product and process training, as well as technical development meeting, for our loyal customers.

Installation and relineOur experienced engineers oversee the safe and timely installation of Metso-supplied parts. Our experts adhere to the most stringent safety standards and are highly trained in OEM workmanship, allowing for a high-quality installation. If necessary, Metso can also guarantee the amount of downtime needed to perform wear part changeouts. Read more onMaintenance and repairs.

Grinding circuit optimizationMetso process experts help in solving complex operational issues using analytical techniques, laboratory testing, and advanced control systems. Whether you need to optimize a piece of equipment, a circuit, or your entire plant, we have the tools and technology to help you make it happen. Read more onProcess optimization and controls.

Life Cycle ServicesMetsos pre-packaged solutions are designed to assist you in meeting your business goals, from start-up to shutdown to end-of-life. We can support you on a specific activity or over a larger scope, combining elements from our large portfolio of services with unique commercial models. Read more onLife Cycle Services.

Discover our wide range of mill lining materials. Our ability to combine different materials in the same mill, using each material where it performs the best, enables us to optimize your grinding process.

ball mill liner function | wear parts for industry | qiming casting

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.

mill liners - metso outotec

A mill lining is a customized wear part. Identifying the appropriate type of lining and design is vital for optimizing mill throughput and total grinding costs, including costs for energy, grinding media and maintenance. Furthermore, the design must be constantly optimized to meet your needs. We work closely with our customers and carefully follow their process to make sure the lining we supply is always optimized for current operating conditions.Metso Outotec offers mill linings with materials and designs optimized for each specific application. We can design and supply mill linings for all types of mills - for Metso Outotec mills as well as for competitor mills - and for all parts of the mill. Our wide product range, innovations, knowledge and experience makes us unique. Our approach to lining design is focused on grinding performance, mill uptime and safety.

At Metso Outotec, cooperation with our customers and availability to offer supportand service are of key importance.We have local support close to our customers, several expertise hubs as well as research facilities focused on wear parts development. Metso Outotec's global laboratory network offers unmatched testing and material development. Our wear parts are manufactured in Metso Outotec's global factory network, utilizing the latest technologies and adhering to stringent quality standards. Today we have eleven production units focusing on rubber and Poly-Met wear parts and five foundries for metallic wear parts.

Metso Outotec is widely recognized as a technology leader in mill manufacturing, which makes us much more than a service and wear parts supplier we are true grinding experts. We know the functional parameters, mechanics, kinematics and forces the mill is subjected to in operation. Thinking long term already when buying a mill provides greater opportunities to achieve lower maintenance and operating costs. This, in combination with knowledge about your current operation conditions and targets, is crucial when designing a mill lining.

Developing new materials and solutions together with our customers is at the heart of what we do. By choosing Metso Outotec, you gain access to the latest innovations and can participate in the process of creating them.We pioneered the use of rubber linings and invented Poly-Met, Megaliner and Orebed mill linings. New products are constantly being developed to enhance our customers ever more advancing processes. Our recent innovations include wear reading solutions, Megaliner for heads, Liner Positioning System upgrade, digitalization etc.

By working with a partner who understands the variables affecting grinding performance, you have a great opportunity to maximize mill performance and availability. We are constantly working to optimize your mill lining design according to your targets and current conditions. Our simulation software allows us to predict the performance of the customized lining extremely accurately, which ensures that we deliver the gains we promise. With Metso Outotec, you can be sure that your mill lining is always designed according to your targets, ore and grinding process.

Finding the balance between grinding and discharging requires in-depth knowledge of the grinding process. It is often challenging, as efficient grinding is dependent on many separate parts and parameters.Metso Outotec designs mill linings for all parts of the mill; shell lining, head lining, discharge system and trommel. We can offer a holistic approach to your whole grinding circuit, and we look at how your different wear parts function together

As part of a system solution, the head lining is designed with consideration to the shell lining design. All components must be in balance to minimize the number of maintenance stops. We try to keep the number of individual parts to a minimum, and to ensure that parts do not interfere with each other during installation. Liners that are most subject to wear are made more robust, and whenever possible these high wear parts are designed to be independently replaceable.

The shell lining has a major influence on grinding efficiency. It transforms the mill rotation into charge motion and both profile and spacing must be carefully selected to suit each specific mill. When designing a shell lining, Metso considers the type of grinding, mill size and speed, maintenance schedules, safety, impact levels, efficient use of materials, and many other parameters.

Metsos wear-resistant rubber-covered or cast dischargers come in two general designs radial and curved. The larger the mill, the longer the distance the material must travel before being discharged into the trunnion. A curved discharger design will initiate a flow towards the center of the mill at an earlier stage and ensure that the discharger pan is emptied and ready to be refilled during the next pass through the charge. Prompt removal of material and less backflow will allow the energy to be more efficiently utilized for grinding fresh ore. As less material is recirculated, wear life increases. In addition, increased flow can also contribute to increased throughput and decreased power consumption.

Metso trunnion liners are custom-made to protect your mill trunnions from internal wear. Fit is critical, and our trunnion liners can be made to almost any size or shape. Typical design features include internal spirals or dams to control material flow, flanges for the mounting of trommel screens, inclusion of threaded holes for jacking screws, inspection ports, etc. Metso trunnion liners are grouped into three categories; One-Piece, Replaceable Sleeve and Bolted Wear Elements.

Mill trommels, whether used for sizing or scalping, play a vital role in your grinding circuit. Metsos robust but light-weight trommel frames consist of carefully selected welded profiles that are covered in a protective layer of wear resistant rubber or polyurethane. Adapting flanges, if required are available to suit the design of virtually any trunnion or trunnion liner interface. There are two main types of screen panels modular and customized. The modular trommel panel with snap-on attachment comes in a standard size of 305 x 610 mm. Installation and replacement of the snap-on screen panels is easily accomplished and results in minimal if any impact on mill availability.

As part of a system solution, the head lining is designed with consideration to the shell lining design. All components must be in balance to minimize the number of maintenance stops. We try to keep the number of individual parts to a minimum, and to ensure that parts do not interfere with each other during installation. Liners that are most subject to wear are made more robust, and whenever possible these high wear parts are designed to be independently replaceable.

The shell lining has a major influence on grinding efficiency. It transforms the mill rotation into charge motion and both profile and spacing must be carefully selected to suit each specific mill. When designing a shell lining, Metso considers the type of grinding, mill size and speed, maintenance schedules, safety, impact levels, efficient use of materials, and many other parameters.

Metsos wear-resistant rubber-covered or cast dischargers come in two general designs radial and curved. The larger the mill, the longer the distance the material must travel before being discharged into the trunnion. A curved discharger design will initiate a flow towards the center of the mill at an earlier stage and ensure that the discharger pan is emptied and ready to be refilled during the next pass through the charge. Prompt removal of material and less backflow will allow the energy to be more efficiently utilized for grinding fresh ore. As less material is recirculated, wear life increases. In addition, increased flow can also contribute to increased throughput and decreased power consumption.

Metso trunnion liners are custom-made to protect your mill trunnions from internal wear. Fit is critical, and our trunnion liners can be made to almost any size or shape. Typical design features include internal spirals or dams to control material flow, flanges for the mounting of trommel screens, inclusion of threaded holes for jacking screws, inspection ports, etc. Metso trunnion liners are grouped into three categories; One-Piece, Replaceable Sleeve and Bolted Wear Elements.

Mill trommels, whether used for sizing or scalping, play a vital role in your grinding circuit. Metsos robust but light-weight trommel frames consist of carefully selected welded profiles that are covered in a protective layer of wear resistant rubber or polyurethane. Adapting flanges, if required are available to suit the design of virtually any trunnion or trunnion liner interface. There are two main types of screen panels modular and customized. The modular trommel panel with snap-on attachment comes in a standard size of 305 x 610 mm. Installation and replacement of the snap-on screen panels is easily accomplished and results in minimal if any impact on mill availability.

There are two types of stirred media mills: Vertimills and Stirred Media Detritors. In a stirred media mill, the mill body is static and the charge motion is created by an agitator such as a rotating spiral or impeller.We provide both original body liners and spiral/impeller liners designed as a system for each of the mill sizes of our extensive range of stirred media mills. Our product range includes all the consumables in your mill e.g. body liners, screw liners, impeller arms, retaining screens, and attachment hardware.

More than a liningWhen buying a mill lining from Metso Outotec, you get more than just a wear part. We always do a pre-study and design the lining based on your conditions and targets. Wear and performance monitoring are regularly done to better understand your grinding process and to optimize the lining accordingly. Technical support is offered, and we arrange product and process trainings as well as technical development meetings for our loyal customers.

Installation and relineOur experienced engineers oversee the safe and timely installation of Metso Outotec-supplied parts. Our experts adhere to the most stringent safety standards and are highly trained in OEM workmanship, allowing for a high-quality installation. If necessary, Metso Outotec can also guarantee the amount of downtime needed to perform wear part changeouts. Read more on Maintenance and repairs.

Grinding circuit optimizationMetso Outotec process experts help in solving complex operational issues using analytical techniques, laboratory testing, and advanced control systems. Whether you need to optimize a piece of equipment, a circuit, or your entire plant, we have the tools and technology to help you make it happen. Read more on Process optimization and controls.

Life Cycle ServicesMetso Outotec's pre-packaged solutions are designed to assist you in meeting your business goals, from start-up to shutdown to end-of-life. We can support you on a specific activity or over a larger scope, combining elements from our large portfolio of services with unique commercial models. Read more on Life Cycle Services.

ball mill liners material selection and application

The ball mill liners and grinding media are the largest consumption of wear-resistant iron and steel parts with an annual consumption of 2 million tons in China. With the development of Chinas economic construction, the demand for cement is increasing year by year, and the consumption of wear-resistant materials is also increasing correspondingly, which will consume more metals and increase the production cost of cement. For the cement with special requirements (such as white cement), the quality of cement will be reduced, and the production can not be carried out smoothly. According to the cement output in 2003, more than 60000 tons of high-quality wear-resistant steel are needed for mill liners only. Moreover, the materials used for lining board production in China are uneven, and the actual consumption can be nearly 100000 tons. According to the characteristics of the cement industry, this paper carefully analyzes the working environment and wear failure reasons of cylinder liner, studies and selects ball mill liners material, and carries out production application.

The main function of the ball mill liner is to protect the mill and use the convex peak of the liner to play the ball to grind and crush the material. Therefore, the main failure mode of the liner is abrasive wear under the repeated impact of small energy. Fig. 1 shows the motion diagram of grinding ball and material. In the movement of grinding bodies and materials, the grinding balls with large diameters are mainly distributed in the outer ring. Most of the grinding balls fall on the bottom of the material bed and only a small part on the liner plate. Due to the buffering effect of materials and the mutual impact between the materials and the grinding body, the running track of the grinding body is disturbed, and the falling point deviates, and the falling height is reduced. As a result, the impact of the abrasive body on the liner is greatly reduced, the impact times and the impact frequency are increased.

The impact of the grinding ball on the ball mill liner is shown in Fig. 2. The impact point diameter D0 of the ball mill is smaller than the effective diameter D of the mill. Through analyses, it is determined that most of the grinding bodies in the bin only hit the lining plate after several times of impact and folding. Therefore, the impact on the lining plate is far less than the impact energy produced by the vertical falling object of 0.95 D (usually the thickness of the lining plate accounts for 0.5 % of the effective diameter).

Figure 3 shows the relative position of grinding balls. When the ball is brought down to a certain height by the rotating ball mill liner, only when x > R1 + R2, the movement direction V0 of Q1 will not change and form a direct impact on the liner; when x = R1 + R2, Q1 and Q2 pass each other, and the movement direction V0 of Q1 will not change greatly, However, a small amount of friction will reduce the impact on the liner, and most of the cases of x < R1 + R2 will not form a direct impact on the liner.

The main force of liner fracture caused by the impact of the abrasive body on the liner is the vertical component of tangential force between the surface of the liner and the contact point of the abrasive body. The size of this force is affected by the shape of liner; the movement state, speed, and direction of the abrasive body, which greatly weakens the strength of direct connection and improves the impact degree of the liner.

In order to improve the service life of the liner, reduce the material consumption and production cost, it is very important to carry out reasonable structural design under the condition of meeting the requirements of the cement grinding process. The large mill imported by Jidong Cement Company, Hebei Taihang Cement Company, and other units has small lining plate size, large plate thickness and bolt free installation, which lays a good design foundation for the application of high hardness materials to lining plate, and makes it possible to greatly increase the service life of lining plate. At present, the design basis of high manganese steel is still used in the lining plate of ball mill in China. From the geometric structure, it is usually thin and large, and there is obvious stress concentration at the bolt installation hole. In order to ensure the stable application of the new type of wear-resistant casting material and give full play to its unique advantages, this point must be taken into account when adopting new high wear-resistant casting materials.

In addition, the installation quality also plays an extremely important role in the reliable service of high hardness materials. After a long time of experimental exploration, it is found that for the application of casting materials with high hardness and high wear resistance, the supplier and application unit of lining plate should cooperate well, so that the user can better understand the characteristics of the new material, and the lining plate can not be suspended or loosened during installation And can get a certain cushion effect. This is easy to do in the installation process of cement mill, which can effectively ensure the good wear resistance of the lining plate.

Up to now, nearly half of the lining materials of ball mill in the domestic cement industry are still made of ordinary high manganese steel. The main failure modes of high manganese steel ball mill liners are as follows:

Fracture failure: the ball mill liner is greatly impacted by the grinding body and materials, especially in the situation of large-scale development of high-efficiency and energy-saving cement mill, the impact energy of lining plate increases. Although the toughness of high manganese steel is very good, the current supply quality can not be guaranteed very well, for example, the carbon content is too high, the manganese carbon ratio is improper, and the water toughening treatment has problems, the fracture failure will occur.

Protrusion deformation: the volume of high manganese steel liner is increased due to the continuous impact of abrasives and materials. At the same time, due to the extension of plastic materials caused by impact, the thickness of mill liner decreases, and the circumferential dimension increases. However, the circumferential dimension of the liner is limited by the overall dimension of the ball mill, and there is not much expansion space to cause the liner to protrude, As a result, the fastening bolts are broken and some lining plates fall off. This phenomenon often occurs in larger mills and in smaller mills.

Wear failure: abrasive wear is one of the main forms of ball mill failure. Even if the lining plate working in the first chamber of large grinding mill bears large stress and the surface is easy to produce work hardening, the hardening layer is very thin. Under the repeated action of abrasive, the metal which is extruded and bulged and the hardened layer impacted by large abrasive edges and corners is easy to crack and peel off. It is found that there is more friction between the plow board and the surface of the plow board under the condition of grinding and hardening.

Through the analysis of the working condition of the liner and the failure analysis of the high manganese steel liner, we realize that it is safe and effective to select the material with high hardness and high wear resistance with good comprehensive mechanical properties according to the working conditions of the cement mill.

Most of the ball mills used for cement production are tube mills with length diameter ratio L / d > 2.5. The mill has a coarse grinding bin and a fine grinding bin (some of which are three bins). The coarse grinding bin is mainly used for crushing and the fine grinding bin is mainly for grinding. The liner plates of the primary mill are mainly stepped liner and wavy liner, and the liner plates of some new high efficiency and energy-saving mills are not separated from their basic forms. The main forms of the fine grinding bin are pattern lining plate, small corrugated lining plate, and flat-lining plate. The effect of the coarse grinding chamber and fine grinding chamber is different, and the ball diameter of the grinding body loaded is different, and the impact on the lining plate is also very different. With the same mill diameter, the diameter of the grinding body in the coarse grinding chamber is large, the material fragmentation is also large, the impact on the lining plate is large, and the wear speed is high; the situation of the fine grinding bin is much better. When choosing lining materials, different materials must be determined according to different conditions.

Industrial growth increases the consumption of wear-resistant parts and then stimulates and drives the development of the wear-resistant material industry. The production process, mechanical properties, and industrial application effect of 40-50 typical brands of wear-resistant steel materials have been industrialized, and the process characteristics of various varieties and small batch have been formed. After many years of production and research of wear-resistant materials, it is considered that the application of multi Alloying High Chromium Cast Iron in the coarse grinding bin of mill with size less than or equal to 3.0 m can be used safely and stably with excellent wear resistance effect and comprehensive economic effect; The application of medium carbon low alloy chromium manganese steel in the roughing bin of the mill with a diameter of fewer than 3 m has good wear resistance and appropriate comprehensive mechanical properties. In general, many kinds of wear-resistant steel materials can be selected for the fine grinding bin, and the medium carbon low-alloy chromium manganese steel developed and produced by us has achieved good results. If there is a strong investment ability, the application of high chromium cast iron can achieve the effect of no replacement for many years, and the comprehensive economic and social benefits are more prominent.

All brand names, model names or marks are owned by their respective manufacturers. MGS Casting has no affiliation with the OEM. These terms are used for identification purposes only and are not intended to indicate affiliation with or approval by the OEM. All parts are manufactured by, for and warranted by MGS Casting and are not manufactured by, purchased from or warranted by the OEM.

ball mill liners selection and design | ball mill rubber liner

The ball mill liners are located on the inner surface of the ball mill barrel, which protects the barrel from the direct impact and friction of the grinding media and the material. The ball mill liners material and shape are different which base on requirements. When the grinding media contacts with different shape of ball mill liners, the movement state will also change, thus enhancing the crushing effect on the material. This design of the mill liners effectively improves the grinding efficiency of the ball mill machine, increases production, and reduces metal consumption.

The grinding mill liners are the main wearing part of the ball mill equipment. The ball mill liner replacement should in time when the lining plate is excessively worn. Therefore, the selection and design of mill liners have always been of great concern to users.

As one of professional ball mill liners manufacturers, we summarize the main functions of the three-point ball mill liners. It mainly involves the protection of the barrel and the control of the grinding medium.

The mill liner is installed inside the ball mill barrel, separating the grinding media from the barrel, effectively buffering the direct impact of the grinding media on the barrel. Therefore, the barrel is protected, and the service life of the barrel and the entire ball mill equipment is prolonged. The ball mill liners are embedded with the barrel, and at the same time, the rigidity of the barrel is enhanced.

Due to the special shape of the grinding mill liner surface, the grinding media contacts the grinding mill liners, and the huge friction force drives the steel ball upward. The steel ball is lifted to a certain height and dropped, while impacting and grinding materials.

Angle spiral grinding mill liner and cone classification liner have automatic classification function, which can make grinding media of different quality in the cylinder carry out reasonable forward classification along the axial direction of the mill and the change of material size. The automatic grading ball mill liners enable the larger steel balls in the barrel to be concentrated at the feed end to crush larger materials, while the smaller steel balls are concentrated at the discharge end to crush smaller materials.

Different ball mill equipment is suitable for different grinding materials, and the type of grinding mill liners selected will also be different. For example, is the rod mill liners the same as the sag mill liner design? Which type of cement mill liner should be used to grind cement in order to reduce the frequency of ball mill liner replacement as much as possible?

According to the material classification, the common ball mill liners mainly include high manganese steel mill liners, alloy steel mill liners, rubber mill liners, ceramic mill liners and magnetic mill liners.

The mainstream ball mill liners materials currently used in the market are alloy steel and rubber. Alloy steel mill liner is wear-resistant and impact-resistant. Alloy steel has good physical and chemical properties due to its alloy properties, and its service life is more than twice that of high-manganese steel. The ball mill rubber liner has a high wear resistance index, high rebound rate, and high abrasion resistance and tear strength. It also has the advantage of reducing noise.

According to different grinding requirements, ball mill liners are roughly divided into 9 types, which are wedge-shaped, corrugated, flat-convex, flat, stepped, elongated, rudder-shaped, K-shaped ball mill rubber liner and B-shaped ball mill rubber liner. These 9 kinds of grinding mill liners can be classified into two categories: smooth grinding mill liner and unsmooth grinding mill liner.

The smooth grinding mill liner has a large sliding property, has a strong grinding effect, and is suitable for fine grinding processes. The friction of the unsmoothed grinding mill liner is large, which can improve the material and steel ball very well, and has strong agitation effect, so it is more suitable for rough grinding process.

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.