It is not allowed to have the shrinkage cavity, shrinking porosity, gas porosity, inclusion, and other cavity defects on the section including plane pasting through the pouring gate and the ball centre.
The chemical composition of the high chromium type product should conform to the below table. We can also manufacture the product with special chemical composition in accordance with the requirements of the customers.
The environment in primary ball milling can best be described by giving equal considerations to both impact and abrasive conditions. The relatively large ball sizes employed [3 4 (75 100 mm)] contribute a significant impact component to the overall wear. The number of impacts in primary ball mills are far more frequent but have less magnitude than those experienced in SAG mills. The increased frequency is due to the Increase in charge volume (35 40% versus 5 10%), higher mill speeds, and the larger number of balls per unit charge weight. The lower impact forces are due to a combination of both smaller ball masses and lower drop heights resulting from the use of smaller balls and smaller mill diameters, respectively.
The feed ore in primary grinding mills is typically very abrasive owing to its particle size, shape, and mineralogy. Wear speeds approaching or exceeding 20 m/hr. have been measured for very abrasive Au. Cu, and Mo ores, while wear speeds on the order of 10-15 m/hr. have been encountered in softer primary ores.
Steel grinding media used in primary grinding must be designed for maximum abrasive wear resistance while maintaining good toughness. Toughness is particularly important in grate discharge mills where pulp levels at the discharge end of the mill can approach zero. Moroz and Lorenzetti (1981) found that maximum abrasion resistance is achieved by the combination of alloying with maximum amounts of carbon and heat treating the balls to their optimal microstructure.
High Cr media for primary grinding will typically contain maximum levels of eutectic carbide (30 35% by volume) and are heat treated to their maximum hardness (HRC 65 68). However, not many high Cr balls are used in primary grinding because the improvement obtained in wear resistance relative to steel, typically 25 30%, is not enough to offset Its higher cost.
In primary ball milling, wear speed is largely independent of ball diameter and mill volume. (The same is true for secondary, tertiary, and regrind grinding.) In these applications, Equation 4 can be used to quantitatively predict how ball size and ball volume charges will affect wear rates. For example, a 5% increase in charge volume (42% versus 40%) will increase hourly ball consumption by 5%. If a corresponding 5% increase in feed rate is not also achieved, then the wear rate (lbs./ton) will be increased. The same analysis can be made for ball size.
In secondary ball milling, abrasive and corrosive conditions predominate. The smaller balls [< 2, (65 mm)] typically used in secondary milling environments effectively reduce the impact component of wear to the point where grinding media must be primarily designed to reduce abrasive and corrosive wear. It can be seen in Figure 3 that the range of wear speeds in secondary grinding widely overlap the range of wear speeds measured in primary grinding. This represents the large variations in abrasive and corrosive wear conditions found at the various testing locations. The best way to compare primary versus secondary grinding conditions is to review MBWT data from primary and secondary applications for the same mill. This comparison is presented in Table IV. The Wear Speeds in secondary grinding are found to be 25 40% lower than those seen in primary milling when grinding the same, but finer, ore. This comparison shows that the reduction of the impact component of wear due to the smaller media size offsets the increase in an abrasive wear expected when grinding to finer product sizes.
The performance of high Cr balls in secondary grinding depends on the abrasive/corrosive environment of the mill. In most secondary Au, Cu, and Mo grinding, the relative wear rates of high Cr compared to forged steel show a performance improvement of 25 30%, similar to that seen in primary grinding. However, for corrosive environments with low abrasion, the high Cr ball can result In Improvements of 50% or more compared to forged steel. This is particularly true for some of the secondary grinding (primary ball mills) of magnetic iron ores. In magnetic iron ore grinding, the silica levels are continually being decreased from crushing to rod milling to ball milling by intermediate concentration steps. Subsequently, the wear environment becomes progressively less abrasive. Meulendyke, Moroz, and Smith (1987) reported that it is in the low abrasive environments where the corrosive component of wear can become quite significant. In these environments, if the proper high Cr alloy is used to avoid corrosion pitting, then high Cr balls can become cost-effective.
Max Feeding size <25mm Discharge size0.075-0.4mm Typesoverflow ball mills, grate discharge ball mills Service 24hrs quotation, custom made parts, processing flow design & optimization, one year warranty, on-site installation.
Ball mill, also known as ball grinding machine, a well-known ore grinding machine, widely used in the mining, construction, aggregate application. JXSC start the ball mill business since 1985, supply globally service includes design, manufacturing, installation, and free operation training. Type according to the discharge type, overflow ball mill, grate discharge ball mill; according to the grinding conditions, wet milling, dry grinding; according to the ball mill media. Wet grinding gold, chrome, tin, coltan, tantalite, silica sand, lead, pebble, and the like mining application. Dry grinding cement, building stone, power, etc. Grinding media ball steel ball, manganese, chrome, ceramic ball, etc. Common steel ball sizes 40mm, 60mm, 80mm, 100mm, 120mm. Ball mill liner Natural rubber plate, manganese steel plate, 50-130mm custom thickness. Features 1. Effective grinding technology for diverse applications 2. Long life and minimum maintenance 3. Automatization 4. Working Continuously 5. Quality guarantee, safe operation, energy-saving. The ball grinding mill machine usually coordinates with other rock crusher machines, like jaw crusher, cone crusher, to reduce the ore particle into fine and superfine size. Ball mills grinding tasks can be done under dry or wet conditions. Get to know more details of rock crushers, ore grinders, contact us!
Ball mill parts feed, discharge, barrel, gear, motor, reducer, bearing, bearing seat, frame, liner plate, steel ball, etc. Contact our overseas office for buying ball mill components, wear parts, and your mine site visits. Ball mill working principle High energy ball milling is a type of powder grinding mill used to grind ores and other materials to 25 mesh or extremely fine powders, mainly used in the mineral processing industry, both in open or closed circuits. Ball milling is a grinding method that reduces the product into a controlled final grind and a uniform size, usually, the manganese, iron, steel balls or ceramic are used in the collision container. The ball milling process prepared by rod mill, sag mill (autogenous / semi autogenous grinding mill), jaw crusher, cone crusher, and other single or multistage crushing and screening. Ball mill manufacturer With more than 35 years of experience in grinding balls mill technology, JXSC design and produce heavy-duty scientific ball mill with long life minimum maintenance among industrial use, laboratory use. Besides, portable ball mills are designed for the mobile mineral processing plant. How much the ball mill, and how much invest a crushing plant? contact us today! Find more ball mill diagram at ball mill PDF ServiceBall mill design, Testing of the material, grinding circuit design, on site installation. The ball grinding mill machine usually coordinates with other rock crusher machines, like jaw crusher, cone crusher, get to know more details of rock crushers, ore grinders, contact us! sag mill vs ball mill, rod mill vs ball mill
How many types of ball mill 1. Based on the axial orientation a. Horizontal ball mill. It is the most common type supplied from ball mill manufacturers in China. Although the capacity, specification, and structure may vary from every supplier, they are basically shaped like a cylinder with a drum inside its chamber. As the name implies, it comes in a longer and thinner shape form that vertical ball mills. Most horizontal ball mills have timers that shut down automatically when the material is fully processed. b. Vertical ball mills are not very commonly used in industries owing to its capacity limitation and specific structure. Vertical roller mill comes in the form of an erect cylinder rather than a horizontal type like a detachable drum, that is the vertical grinding mill only produced base on custom requirements by vertical ball mill manufacturers. 2. Base on the loading capacity Ball mill manufacturers in China design different ball mill sizes to meet the customers from various sectors of the public administration, such as colleges and universities, metallurgical institutes, and mines. a. Industrial ball mills. They are applied in the manufacturing factories, where they need them to grind a huge amount of material into specific particles, and alway interlink with other equipment like feeder, vibrating screen. Such as ball mill for mining, ceramic industry, cement grinding. b. Planetary Ball Mills, small ball mill. They are intended for usage in the testing laboratory, usually come in the form of vertical structure, has a small chamber and small loading capacity. Ball mill for sale In all the ore mining beneficiation and concentrating processes, including gravity separation, chemical, froth flotation, the working principle is to prepare fine size ores by crushing and grinding often with rock crushers, rod mill, and ball mils for the subsequent treatment. Over a period of many years development, the fine grinding fineness have been reduced many times, and the ball mill machine has become the widest used grinding machine in various applications due to solid structure, and low operation cost. The ball miller machine is a tumbling mill that uses steel milling balls as the grinding media, applied in either primary grinding or secondary grinding applications. The feed can be dry or wet, as for dry materials process, the shell dustproof to minimize the dust pollution. Gear drive mill barrel tumbles iron or steel balls with the ore at a speed. Usually, the balls filling rate about 40%, the mill balls size are initially 3080 cm diameter but gradually wore away as the ore was ground. In general, ball mill grinder can be fed either wet or dry, the ball mill machine is classed by electric power rather than diameter and capacity. JXSC ball mill manufacturer has industrial ball mill and small ball mill for sale, power range 18.5-800KW. During the production process, the ball grinding machine may be called cement mill, limestone ball mill, sand mill, coal mill, pebble mill, rotary ball mill, wet grinding mill, etc. JXSC ball mills are designed for high capacity long service, good quality match Metso ball mill. Grinding media Grinding balls for mining usually adopt wet grinding ball mills, mostly manganese, steel, lead balls. Ceramic balls for ball mill often seen in the laboratory. Types of ball mill: wet grinding ball mill, dry grinding ball mill, horizontal ball mill, vibration mill, large ball mill, coal mill, stone mill grinder, tumbling ball mill, etc. The ball mill barrel is filled with powder and milling media, the powder can reduce the balls falling impact, but if the power too much that may cause balls to stick to the container side. Along with the rotational force, the crushing action mill the power, so, it is essential to ensure that there is enough space for media to tumble effectively. How does ball mill work The material fed into the drum through the hopper, motor drive cylinder rotates, causing grinding balls rises and falls follow the drum rotation direction, the grinding media be lifted to a certain height and then fall back into the cylinder and onto the material to be ground. The rotation speed is a key point related to the ball mill efficiency, rotation speed too great or too small, neither bring good grinding result. Based on experience, the rotat
ion is usually set between 4-20/minute, if the speed too great, may create centrifuge force thus the grinding balls stay with the mill perimeter and dont fall. In summary, it depends on the mill diameter, the larger the diameter, the slower the rotation (the suitable rotation speed adjusted before delivery). What is critical speed of ball mill? The critical speed of the ball mill is the speed at which the centrifugal force is equal to the gravity on the inner surface of the mill so that no ball falls from its position onto the mill shell. Ball mill machines usually operates at 65-75% of critical speed. What is the ball mill price? There are many factors affects the ball mill cost, for quicker quotations, kindly let me know the following basic information. (1) Application, what is the grinding material? (2) required capacity, feeding and discharge size (3) dry or wet grinding (4) single machine or complete processing plant, etc.
Our automatic production line for the grinding cylpebs is the unique. With stable quality, high production efficiency, high hardness, wear-resistant, the volumetric hardness of the grinding cylpebs is between 60-63HRC,the breakage is less than 0.5%. The organization of the grinding cylpebs is compact, the hardness is constant from the inner to the surface. Now has extensively used in the cement industry, the wear rate is about 30g-60g per Ton cement.
Grinding Cylpebs are made from low-alloy chilled cast iron. The molten metal leaves the furnace at approximately 1500 C and is transferred to a continuous casting machine where the selected size Cylpebs are created; by changing the moulds the full range of cylindrical media can be manufactured via one simple process. The Cylpebs are demoulded while still red hot and placed in a cooling section for several hours to relieve internal stress. Solidification takes place in seconds and is formed from the external surface inward to the centre of the media. It has been claimed that this manufacturing process contributes to the cost effectiveness of the media, by being more efficient and requiring less energy than the conventional forging method.
Because of their cylindrical geometry, Cylpebs have greater surface area and higher bulk density compared with balls of similar mass and size. Cylpebs of equal diameter and length have 14.5% greater surface area than balls of the same mass, and 9% higher bulk density than steel balls, or 12% higher than cast balls. As a result, for a given charge volume, about 25% more grinding media surface area is available for size reduction when charged with Cylpebs, but the mill would also draw more power.Get in Touch with Mechanic