After the mill there would be a screen with 1mm opening, fines to spirals, coarse back to the mill. I used rod mills for such a coarse grind, but the handling of the rods is not as easy as if you use balls. So the question came up what a grate discharge ball mill would do here. I never used one.
WhatsApp: +86 18203695377The type of ball mill liner known as a grate liner is designed for discharge efficiency. It allows the discharge of ground materials via slots. With the Magotteaux range of alloys and their experience a longer lifetime and optimal grinding can be achieved. Designs of grate liners depend on their drilling pattern, mill speed, grinding media ...
WhatsApp: +86 18203695377Furthermore, it should be observed that a grate discharge ball mill converts about 20% more energy than an overflow discharge mill with the same shell dimensions. Ball mill shells are often furnished with two manholes. Ball mills with small balls or cylpebs can produce the finest product of all tumbling mills. 80% minus 74 microns is a ...
WhatsApp: +86 18203695377It embodies the peripheral discharge with grates, large forgedsteel balls, and the principal features of the modern ball mill. The results approach presentday practice, the chief differences being that the mechanical construction has been improved in the modern types. Crushing Action of BallMill
WhatsApp: +86 18203695377Ball Mills. 【 Capacity 】 T/H. 【 Max Feeding Size 】 <25mm. 【 Discharge Size 】 【 Types 】Overflow ball mills, grate discharge ball mills. 【Advantages】 Designed for long service life and minimum maintenance, can grind and homogenize mineral ores down to the nano range, with a large processing capacity.
WhatsApp: +86 18203695377Ball mills can be classified into two type Based on different Ore discharging types: grate ball mill and overflow ball mills. In this article, we will compare the two types to help you choose the ...
WhatsApp: +86 18203695377where an approximate figure for the constant is for rod mills, for overflow ball or pebble mills and for grate discharge ball or pebble mills. ç is specific gravity of grinding media (for rods or balls normally ) q is the charge volume in fraction of mill volume (40 % = ) nc is the mill speed in fraction of critical speed
WhatsApp: +86 18203695377It is better to select a grate discharge ball mill when the required discharge size is ~ mm. b. Overflow discharge ball mill. The overflow discharge ball mill is designed with no sieve plate so that the ore pulp can be discharged directly without filtration. It is very simple in structure and convenient for maintenance.
WhatsApp: +86 18203695377Grate discharge type ball mill has a higher processing capacity, but the product size is relatively coarse (), suitable for the first stage of grinding operations. The grinding steel ball inside the barrel of the grate ball mill is filled in accordance with different sizes and proportions. When the grinding ball is lifted to a certain ...
WhatsApp: +86 18203695377To achieve this goal, it is proposed a new automatic control system (ACS) for ore volumetric filling of gratedischarge ball mill in a closed grinding cycle using model predictive control and ...
WhatsApp: +86 18203695377Unlike the grate ball mill, the overflow type ball mill has a simple structure, and the discharge method is based on the gravity flow of the slurry to discharge the ore. The product size of the overflow discharge ball mill is generally less than, which is suitable for concentrate regrinding operation and can be used as onestage grinding ...
WhatsApp: +86 18203695377Grate discharge ball mill is a traditional ball mill with forced discharge method by grate lining plate. The grate plate is installed at the ball mill discharging end. Materials with qualified size enter the fanshaped chamber (composed of ribs and dustpanshaped liner) through the small holes on the grate lining plate and then rise to the ...
WhatsApp: +86 18203695377In grate ball mill work there are no discharge head liners. The discharge grates and grate assembly replace these parts. Mill LINER BOLTS. 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 ...
WhatsApp: +86 18203695377Material transport or discharge function describes how particles are discharged out of the mill (Man, 2001) and was approximated in a different way in each type of ball mill transport was described by using a diagonal classification matrix to represent the size dependent material flow through the mill in the matrix models (Lynch, 1977).
WhatsApp: +86 18203695377A reliable mill lining supplier will always consider these factors when offering the best solution for conversion of a ball mill from an overflow to a grate discharge. For suitable mills, Outotec is able to provide modelling of the mill before and after conversion to quantify the process benefits of the conversion, and then design the ...
WhatsApp: +86 18203695377Axial transport and grate discharge of a coarse rock and in a ball mill were also studied by Cleary (2006). Cleary et al. (2008) then used a slice model to explore the effect of different coarse ...
WhatsApp: +86 18203695377As secondary ball mills are usually fed a relatively (compared to SAG mills) fine F80 and have high recirculating loads and produce product fineness of the P80 100 to 160 micron range, fitting a grate discharge needs to be carefully considered.
WhatsApp: +86 18203695377To determine the power that a dry grinding needs, full grate discharge mill Equation 1 is multiplied by the factor of A multicompartment ball mill consists of two or more grate discharge ball mills in series. The same equation is used to calculate the power that each ball mill compartment should draw. The total power is
WhatsApp: +86 18203695377The ball mill machine is known as a ball grinding machine. It is a wellknown ore grinding machine and is widely used in mining, construction, and aggregate application. JXSC started manufacture the ball mill grinder since 1985, supply globally service includes flow design, manufacturing, installation, and free operation training in mining ...
WhatsApp: +86 18203695377Comchambered with the design of Φ × 13m threechamber ball mill, the design process of ball mill is described in detail. General arrangement of the mill Filling rate of grinding body in each ...
WhatsApp: +86 18203695377Here we consider an overflow ball mill with feed and discharge of slurry as well as resident slurry included. This is modelled using the fully coupled DEM+SPH method. ... both with overflow and grate discharge. An industrial ball mill was then laser scanned and surveyed, including measurements of residence time distribution. Simulations using ...
WhatsApp: +86 18203695377It was found that the prediction for mills with diameters of 2000 and 3000 mm based on the training model developed by mills with diameter less than 254 mm could be achieved with an accuracy of 80 ...
WhatsApp: +86 18203695377Pulp lifter assembly is one of the important components at the discharge ends of gratedischarge grinding mills. It discharges grinded materials out through the discharge trunnion ... Slurry densities and holdup were measured for open circuit grinding tests in a laboratory overflow ball mill of 03 m diam by m long, by emptying and drying ...
WhatsApp: +86 18203695377Grate ball mill discharge side cover liner inner sleeve shaft liner liner bars key. Different of feeding device of grate ball mill. 1. The feeders of ball mill are: drum type, worm type and combined type, and their structures are shown as (a), (b) and (c) in the figure.
WhatsApp: +86 18203695377Both are set according to operating conditions: • internal CSTRs in ball mills: X = 40% of top size ball diameter, and  = ; • internal CSTRs in rod mills: X = P90 (sieve dimen sion larger than 90% of the particles) in the CSTRs, and  = ; • grate discharge mills: X must match the grate aper ...
WhatsApp: +86 18203695377The table below lists a few sizes of Grate Discharge BallTube mills with their typical capacity based on wet grinding 8 mesh feed to 100 mesh in closed circuit with a suitable classifier. For dry grinding reduce capacity approximately 30% to 50%. Tube Mill Capacity. The table below lists a few sizes of Pebble Mills with their typical capacity ...
WhatsApp: +86 18203695377The influence of pulp composition and feed rate on holdup weight and mean residence time of solids in gratedischarge ball mill grinding. Int. J. Miner. Process. (1981) Klimpel et al. The mass transport of slurry and solid in a laboratory overflow ball mill ... The discharge end design of a ball mill plays an important role in discharging ...
WhatsApp: +86 18203695377(1) Rao Latchireddi, (1) Raj K Rajamani and (2)Sanjeeva Latchireddi. (1) University of Utah, (2) EEMill Solution LLC, USA.
WhatsApp: +86 18203695377For overflow ball mills, the charge should not exceed 45% of the mill volume . For grate discharge mills, the charge should occupy about 50% of the mill volume . Bond developed a relationship that can be used to determine the percent charge by volume as a function of the vertical height above the charge, He, and the radius of the mill, R,,
WhatsApp: +86 18203695377A set of experimental test work has been carried out in a continuous pilot ball mill of X m (diameter X length) at different mill speeds, percent solids and discharge mechanism. The results of study on material flow through a grate discharge tumbling mill verses an overflow tumbling mill are presented to emphasize the effect of ...
WhatsApp: +86 18203695377The Perfect Mixing model is based on a population balance of particles entering the mill, breaking into smaller sizes, and discharging as product. For a mill operating in steadystate, the diagram in Figure 1 below represents the balance for a given size fraction: Figure 1. Schematic diagram of the steadystate population balance adopted by the ...
WhatsApp: +86 18203695377Due to the difference of ore discharge modes between the two mills, the productivity of grate ball mill is 10%25% higher than that of overflow ball mill. When twostage grinding is required, the first stage uses grate ball mill and the second stage uses overflow ball mill. When regrinding of coarse concentrate is required, overflow ball mill ...
WhatsApp: +86 18203695377For our purposes, the experimental data on continuous grinding of limestone, feldspar, and quartz in a cm long by 40. 6 cm diameter gratedischarge ball mill was found suitable. The feed rate of the solids, the weight percent of solids in the slurry, and the feed size distribution were the only operating variables covered.
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