Fig. 1 shows the cross section of an overflow rod mill, Fig. 2 an overflow ball mill, and Fig. 3 a diaphragm (grate) discharge ball mill. Mineral ore comminution is generally a feed preparation step for subsequent processing stages. Grinding, the fine product phase of comminution, requires a large capital investment and frequently is the area ...
WhatsApp: +86 18838072829tion. In 1960, the larger rod and ball mills had diameters in the range to m ( to ft.). However, during the 1960s, the diameters of the mills increased to m (15 ft) for rod mills and m ( ft) for ball mills. In addition, the diameters of the ball mills that were being designed at that time were m (18 ft).
WhatsApp: +86 18838072829Overcharging results in poor grinding and losses due to abrasion of rods and liners. Undercharging also promotes more abrasion of the rods. The height (or depth) of charge is measured in the same manner as for ball mill. The size of feed particles to a rod mill is coarser than for a ball mill. The usual feed size ranges from 6 to 25 mm.
WhatsApp: +86 18838072829Ball mill: Ball mills are the most widely used one. Rod mill: The rod mill has the highest efficiency when the feed size is <30mm and the discharge size is about 3mm with uniform particle size and light overcrushing phenomenon. SAG mill: When the weight of the SAG mill is more than 75%, the output is high and the energy consumption is low ...
WhatsApp: +86 18838072829For rod, ball, or pebble mills the peak is usually near Vp = .50, while actual observations as low as V= .42 have bean made in some ball mills (Rowland, 1973). See Figure 2. Power draw is not significantly affected by the presence of the slurry in the mill. While the presence of the slurry will effect the charge density, the charge swelling ...
WhatsApp: +86 18838072829The reason why rod mill is called rod mill is that its grinding medium is steel rod, while the grinding medium of ball grinding mill is steel ball. Because the shape of the grinding media is different, the working mode has its own characteristics. When the steel rod is in motion, the gap between the rods is a regular long strip, which plays a ...
WhatsApp: +86 18838072829Fig 1 Cross sections of a rod mill and a bar mill. Ball mills. Ball mill (Fig 1) is same kind of mill as rod mill, except that it is filled with balls instead of rods. Because of balls have greater ratio of surface area than rods they are more suitable for fine grinding. Balls are also lighter, so the kinetic energy of a single dropping ball is ...
WhatsApp: +86 18838072829In comparison to conventional tumbling mills,, rodand ball mills, the grinding media in an AG mill derive from the feed ore itself (Gupta and Yan, 2016;Hahne et al., 2003).
WhatsApp: +86 18838072829The mill product can either be finished size ready for processing, or an intermediate size ready for final grinding in a rod mill, ball mill or pebble mill. AG/SAG mills can accomplish the same size reduction work as two or three stages of crushing and screening, a rod mill, and some or all of the work of a ball mill.
WhatsApp: +86 18838072829Ball mills use steel balls as grinding media, and there is point contact between the steel balls. Rod mill. Rod mills usually use steel rods with a diameter of 50100mm as grinding media, and the ...
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WhatsApp: +86 18838072829The basic parameters used in ball mill design (power calculations), rod mill or any tumbling mill sizing are; material to be ground, characteristics, Bond Work Index, bulk density, specific density, desired mill tonnage capacity DTPH, operating % solids or pulp density, feed size as F80 and maximum 'chunk size', product size as P80 and maximum and finally the type of circuit open/closed ...
WhatsApp: +86 18838072829Introduction Rod Mill Used as the primary comminution unit in a grinding circuit. Rods are placed parallel along the length of the rod mill. Rods are 150mm shorter than the mill length. Breakage occurs more from cascading than cateracting. The product size distribution is narrower than a ball mill but significantly coarser.
WhatsApp: +86 18838072829Ball mill The capacity of ball mills is ~ 615t/h, and the discharge particle size of the ground material is ~ Rod mill The capacity of rod mills is ~ 180t/h, and the discharge particle size is ~ 2. Different grinding media Ball mill
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WhatsApp: +86 18838072829Grinding Mills: Ball Mill Rod Mill Design Parts Common types of grinding mills include Ball Mills and Rod Mills. This includes all rotating mills with heavy grinding media loads. This article focuses on ball and rod mills excluding SAG and AG mills. Although their concepts are very similar, they are not discussed here. Photographs of a glass ended laboratory ball mill show action of ball ...
WhatsApp: +86 18838072829Ball mills and rod mills are two types of grinding mills that are often used for this purpose. Both types of mills have their advantages and disadvantages, and the choice between the two depends on several factors. Ball Mills: Ball mills are cylindrical devices used to grind materials such as chemicals, ores, and paints.
WhatsApp: +86 18838072829These corrections apply both for ball mill and rod mill grinding. Correction factors suggested by Rowland and Kjos [28] that apply for ball mills are given below. (Corrections for rod mills are given in Chapter 8.) 1. Correction for dry grinding, as Bond's work index is carried out under wet conditions, 2.
WhatsApp: +86 18838072829GRINDING MILLS BALL Mills, SAG Mills, AG Mills ROD Mills. We refurbish, design and manufacture an extensive range of highquality mills and mill components to exacting standards, offering you a turnkey service that's backed by two decades of engineering expertise. BROCHURE. Finite Element Analysis (FEA) Ball Charge Trajectory Modelling ...
WhatsApp: +86 18838072829Rods in place weigh approximately 400 pounds per cu. ft. and balls in place approximately 300 pounds per cu. ft.. Thus, quantitatively, less material can progress through the voids in the rod mill grinding media than in the ball mill, and the path of the material is more confined.
WhatsApp: +86 18838072829Autogenous mill Autogenous or autogenic mills are socalled due to the selfgrinding of the ore: a rotating drum throws larger rocks of ore in a cascading motion which causes impact breakage of larger rocks and compressive grinding of finer particles.
WhatsApp: +86 18838072829EF4 Oversized Feed when being fed a coarser than optimum feed, this factor applies to rod milling and ball milling. However, the most frequent use is found in conjunction with single stage ball milling. This is the one efficiency factor that is related to Work Index as is seen in the following equation:
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