## Ball Mill Work Inde Calculation

Application

Ball Mill Design/Power Calculation The basic parameters used in ball mill design (power calculations), rod mill or any tumbling mill sizing are; material to be

# Ball Mill Work Inde Calculation

• ## Ball Mill Design/Power Calculation

The 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 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 ballHow to Size a Ball Mill Design Calculator & FormulaThis Grindability Test or Bond Ball Mill Work Index Procedure is used to determine the Bond Work Index of minus six mesh or finer feed ore samples These equation application methods are used to process <1/2″ ore samples in a Ball Mill using a standard ball charge Below describes in general terms the Bond Work IndexBond Work Index Procedure and Method

• ## Ball Mill Design/Power Calculation LinkedIn

· Ball Mill Power Calculation Example A wet grinding ball mill in closed circuit is to be fed 100 TPH of a material with a work index of 15 and a size distribution of 80% passing ¼ inch (6350Calculation of energy required for grinding in a ball,A bond ball mill work index is then performed on the mill product for the design of sagball mill circuits this is important because it was found that there was a 115 kwht higher ball mill work index if the 335 mm ball mill test feed size is moretget priceball mill work index calculationThe ball mill work index laboratory test is conducted by grinding an ore sample prepared to 100% passing 336 mm (6 mesh) to product size in the range of 45150 µm (325100 mesh), thus determining the ball mill work index (Wi B or BWi) The work index calculations across a narrow size range are conducted using the appropriate laboratory work index determination for the material size ofBond Work Index an overview | ScienceDirect Topics

• ## (PDF) A quick method for bond work index approximate

· This study aims to develop a new approach toward estimating the Bond ball mill work index (BBWI) by applying a series of kinetic grinding tests with Bond standard mill Establishing aIn 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 andCalculate and Select Ball Mill Ball Size for Optimum GrindingIt has been recognized that the grindability of an ore in a ball mill is a function of both feed and mill parameters: Work index, W i; Largest particle size and size distribution ; Density of solids and slurry; Mill diameter; Rotational speed; Rowland and Kjos (1980) defined the largest ball size needed based on these parameters: dâ†“B = 254 [(Fâ†“80 / k) â†‘05 (Ï â†“sAMIT 135: Lesson 7 Ball Mills & Circuits – Mining Mill

• ## ball mill work index calculation

Calculation of energy required for grinding in a ball mill The Bond work index, W i, as an indicator of the grindability of raw materials is not a material constant but rather it changes with change of size of the grinding productTherefore, in practice we can expect some difficulties and errors when the energy consumption is determined according to this formula in the case when, for a given· Ball Mill Power Calculation Example A wet grinding ball mill in closed circuit is to be fed 100 TPH of a material with a work index of 15 and a size distribution of 80% passing ¼ inch (6350Ball Mill Design/Power Calculation LinkedInNote that the ball mill operating work index is applied only on the portion that needs the additional grinding (Q2), which renders to the AG/SAG mill the credit for the fraction of the material that had been already ground to final product (Q1) To calculate the operating work indices, equations [5] and [6] must be solved The equations contain three unknowns: 1 Q1: the Fines Factor, 2 Q2Application of Operating Work Indices in Autogenous

• ## Calculation of energy required for grinding in a ball mill

The Bond work index, W The grindingproduct size, P, in a Bond ball mill, which is given by the aperture size which passes 80% of the grinding product as a function of the aperture size of the test screen P k, can be expressed by the formula P= P k K 2 These functions for G and P enable us to calculate the value of W i for any other size of grinding product if we know the work index W iThe test determines the Bond Ball Mill Work Index which is used with Bond’s Third Theory of Comminution to calculate net power requirements* Various correction factors may have to be applied W = Wi (10/√P – 10/√F) Where W = Net power consumption in kWh/t Wi = Bond work index (either Imperial or Metric units) P = The 80% passing size of the ground product in µm F = The 80% passingBond Tests | SGScan be determined using the data generated by a conventional Bond ball mill work index test (M ib is NOT the Bond ball work index) M ic and M ih values are also provided as a standard output from a SMC Test ® (Morrell, 2009) The general size reduction equation is as follows (Morrell, 2004 b): f x f x 2 1 i i 4 2 W M x x 1 (1) where M i = Work index related to the breakageUSING THE SMC TEST® TO PREDICT COMMINUTION CIRCUIT PERFORMANCE

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

It has been recognized that the grindability of an ore in a ball mill is a function of both feed and mill parameters: Work index, W i; Largest particle size and size distribution ; Density of solids and slurry; Mill diameter; Rotational speed; Rowland and Kjos (1980) defined the largest ball size needed based on these parameters: dâ†“B = 254 [(Fâ†“80 / k) â†‘05 (Ï â†“s· The grindingproduct size, P, in a Bond ball mill, which is given by the aperture size which passes 80% of the grinding product as a function of the aperture size of the test screen Pk, Can be expressed by the formula P=Pk/K2 These functions for G and P enable us to calculate the value of Wi for any other size of grinding product if we know the work index Wi and aperture size of the screen PkCalculation of energy required for grinding in a ball millThe work index can either be measured in the laboratory (the Bond ball mill work index determination is a common example) or it can be calculated from the operating performance of a millingOperating work index is not the specific energy

• ## CORRELATION BETWEEN BOND WORK INDEX AND

The Bond's standard ball mill is used to determine the work index value of differ ent samples The Bond work index is defined as the kilowatthours per short ton required to break from infinite size to a product size of 80% passing 100 µm If the breakage characteristics of a material remain constant over all size ranges, the calcul ated work index would be expected to remain constant since· Ball Mill Power Calculation Example A wet grinding ball mill in closed circuit is to be fed 100 TPH of a material with a work index of 15 and a size distribution of 80% passing ¼ inch (6350Ball Mill Design/Power Calculation LinkedInBall Mill Batch Process The mill dimensions, (D × L), are 0204 × 0158 m and it is loaded with 65 kg steel balls between 25 and 32 mm in diameter The mill rotates on rolls and its frequency is set to 70 RPM (1667 Hertz) corresponding to 85% of the critical frequency The mill power is P = 162 Watts, calculated by the formula provided by Stamboltzis [7] PMN 99 (6) where M (kg) is theA New Approach to the Calculation of Work Index and the

• ## USING THE SMC TEST® TO PREDICT COMMINUTION CIRCUIT PERFORMANCE

can be determined using the data generated by a conventional Bond ball mill work index test (M ib is NOT the Bond ball work index) M ic and M ih values are also provided as a standard output from a SMC Test ® (Morrell, 2009) The general size reduction equation is as follows (Morrell, 2004 b): f x f x 2 1 i i 4 2 W M x x 1 (1) where M i = Work index related to the breakageThe Bond ball mill work index is one of the most commonly used grindability tests in mining, The work index is used to calculate the energy requirement to grind rocks in the fine size range, below 25 mm into the range of a few hundreds of micrometres Heterogeneous ore types typically are sensitive to the product size of the test, and the work index value changes if the test is performedTestwork: Bond ball mill work index The Bond ball mill grindability test is run in a laboratory until a circulating load of 250% is developed It provides the Bond Ball Mill Work Index which expresses the resistance of material to ball milling This happens after 7–10 grinding cycles, which shows that the procedure is a lengthy and complex one and is therefore susceptible to procedural errors Starting from the firstorderProcedure for determination of ball Bond work index in

• ## Correction of Bond Ball Mill Work Index Test for Closing

It is commonly known that one must run the Bond ball mill work index test such you pick a closing mesh to give a P80 close to desired grind size This is because work index frequently changes as a function of the product size in comminution If target grind size during a project is changed, or if the test is run at the wrong product size, then it is necessarily to provide a correction Thesimplify this method to be able to perform a rapid calculation of a work index This study aims to develop a new approach toward estimating the Bond ball mill work index (BBWI) by applying a series of kinetic grinding tests with Bond standard mill Establishing a series of relationships between grinding parameters and Bond equation parameters, this approach is fast and practical due toKinetic grinding test approach to estimate the ball mill= Bond laboratory ball work index (kWh/tonne) P 1 = closing screen size in microns Gbp = net grams of screen undersize per mill revolution P = 80% passing size of the product in microns F = 80% passing size of the feed in microns Circuit Equipment Configurations – Although the model can be used for a very wide range ofSPECIFIC COMMINUTION ENERGY SMC Testing

• ## Bond Grinding Circuit Efficiency

Closed circuit 8’ dia ball mill to P80 um The ore Test Work Index = Circuit Operating Work Index 9 The Standard Bond Circuit Coarse Ore Bins Fine Ore Bins Screen Crushing Screen Classification Rod Mill Ball Mill THIS IS THE REFERENCE BASIS FOR ALL WORK INDEX EFFICIENCY DETERMINATIONS! 10 2/20/2014 6 Example SAGBall Mill Circuit WI Efficiency Calculation • SAGball circuit F80 =The Bond's standard ball mill is used to determine the work index value of differ ent samples The Bond work index is defined as the kilowatthours per short ton required to break from infinite size to a product size of 80% passing 100 µm If the breakage characteristics of a material remain constant over all size ranges, the calcul ated work index would be expected to remain constant sinceCORRELATION BETWEEN BOND WORK INDEX AND