### Calculate and Select Ball Mill Ball Size for Optimum Grinding

In Grinding, selecting (calculate) the correct or optimum ball size that allows for the best and optimum/ideal or target grind size to be achieved by your ball mill is an important thing for a Mineral Processing Engineer AKA Metallurgist to do. Often, the ball used in ball mills is oversize “just in case”. Well, this safety factor can cost you much in recovery and/or mill liner wear and

More### Ball Mills an overview ScienceDirect Topics

where d b.max is the maximum size of feed (mm); σ is compression strength (MPa); E is modulus of elasticity (MPa); ρb is density of material of balls (kg/m 3); D is inner diameter of the mill body (m).. Generally, a maximum allowed ball size is situated in the range from D /18 to D/24.. The degree of filling the mill with balls also influences productivity of the mill and milling efficiency.

More### Feed Size VS Ball Size Grinding & Classification

To participate in the 911Metallurgist Forums, be sure to JOIN & LOGIN Use Add New Topic to ask a New Question/Discussion about Grinding. OR Select a Topic that Interests you. Use Add Reply = to Reply/Participate in a Topic/Discussion (most frequent). Using Add Reply allows you to Attach Images or PDF files and provide a more complete input. Use Add Comment = to comment on someone else’s

More### Ball Mill an overview ScienceDirect Topics

Ball mills tumble iron or steel balls with the ore. The balls are initially 5–10 cm diameter but gradually wear away as grinding of the ore proceeds. The feed to ball mills (dry basis) is typically 75 vol.-% ore and 25% steel. The ball mill is operated in closed circuit with a particle-size measurement device and size-control cyclones.

More### Effect of ball and feed particle size distribution on the

Jun 01, 2018· Fig. 5 shows the variation of size class 1 (M1) with the milling time for the two feed size distributions. For this coarser feed the 50 + 20+10 mm ball diameter mix breaks the material at a faster rate compared to the other ball matches. The availability of a ball size for a particular feed size ensures breakage occurs at a faster rate.

More### How to Size a Ball Mill -Design Calculator & Formula

A) Total Apparent Volumetric Charge Filling including balls and excess slurry on top of the ball charge, plus the interstitial voids in between the balls expressed as a percentage of the net internal mill volume (inside liners). B) Overflow Discharge Mills operating at low ball fillings slurry may accumulate on top of the ball charge; causing, the Total Charge Filling Level to

More### AMIT 135: Lesson 7 Ball Mills & Circuits Mining Mill

Ball Size as Initial Charge. Commercial ball sizes 10 150 mm; Number, size and mass of each ball size depends on mill load and whether or not the media is being added as the initial charge. For the initial chargin of a mill, Coghill and DeVaney (1937) defined the ball size as a function of the top size of the feed, i.e., dâ†“V = 0.40

More### Ball Mill: Operating principles, components, Uses

The balls which could be of different diameter occupy 30 50 % of the mill volume and its size depends on the feed and mill size. The large balls tend to break down the coarse feed materials and the smaller balls help to form fine product by reducing void spaces between the balls. Ball mills grind material by impact and attrition.

More### Effect of ball and feed particle size distribution on the

Jun 01, 2018· Fig. 5 shows the variation of size class 1 (M1) with the milling time for the two feed size distributions. For this coarser feed the 50 + 20+10 mm ball diameter mix breaks the material at a faster rate compared to the other ball matches. The availability of a ball size for a particular feed size ensures breakage occurs at a faster rate.

More### Optimum choice of the make-up ball sizes for maximum

Sep 01, 2013· Eq. can be used as the basic equation for this relationship, which relates the fraction of the 50.8 mm balls with feed size and the size reduction ratio. Fig. 12 shows the variation of the parameter A′ with the feed size and the mill diameter at fixed values of α = 0.93, μ = 1.83 and N 1 = 1.2.

More### Mine-To-Mill Optimisation: Effect Of Feed Size On Mill

Mine-To-Mill Optimisation: Effect Of Feed Size On Mill Throughput; that will pass through the primary mills and onto the secondary ball mill circuits, alleviating a common bottleneck. Modifying blasting practices to achieve a more suitable mill feed size which varies according to the crushing/grinding circuit can achieve up to a 30%

More### (PDF) Influence of feed size on AG / SAG mill performance

Ag mills are the most sensitive in this respect . in the relationship between feed size and mill performance and manipulate but also on factors such as feed size and ball load (Morrell

More### Experimental Study on the Grinding Rate Constant of a Ball

fraction of feed size R, and S1 as grinding rate con stant K1 in Eq. (3). Silica glass was ground with a ball mill while varying the feed size and ball diameter, and measured K1. (3) An experimental equation was obtained by expressing K1 as a function of feed size and ball diameter. 2. Sample Used and Experimental Method

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