The analysis of the influence of ball sizes in SAG grinding hasn t been developed in detail by considering the effect on process parameters inside the mill grinding efficiency or internal classification Historically a conventional grinding reference has been made on the empirical …

 · Most mills used in mining rely on impact to breakdown rock to a suitable size for downstream processing The impact can be rock on rock such as in an Autogenous Grinding AG mill rock and a small ball charge 10 used in Semi Autogenous Grind …

Even though production was dramatically improved the product size of the secondary ball milling was reduced and recovery increased The results in SAG Mill line 2 are even more dramatic Because of segregation on the coarse feed stockpile SAG mill 2 receives a higher percentage of coarse material …

ness of the models For a given mill to have a combination of feed size ball load mill speed and solids will represent the total load Ball Mill SAG Mill Scw Jb Pc 6 1 N Nc Fresh Feed Water Water Pebble Crusher Screen Cyclones Sump Pump Fig 1 SABC A B milling circuit …

Mill Process Grinding Mills Grinding Mills also know as Semi Autogenous SAG Ball or Regrind Mills are used in the primary or early stages of pulverizing the ore in the process plant This initial grind of the ore is typically completed in two or three stages The mills are driven by large high horsepower electrical motors and the outer …

EFFECTS OF GRINDING MEDIA SHAPES ON BALL MILL PERFORMANCE Niyoshaka Nistlaba Stanley Lameck A dissertation submitted to the Faculty of Engineering and The Built Environment University of the Witwatersrand Johannesburg in fulfilment of the requirements for the degree of Master of Science in Engineering Johannesburg October 2005…

SAG milling extends itself to many applications due to the range of mill sizes available They 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 done by a ball mill SAG mills are also an optimum solution for wet grinding since crushing and screening in these …

are typically SAG mill limited while Apensu ores are ball mill limited in the Ahafo SABC circuit Table 1 Ahafo Ore Properties Ore Source Drop Weight A b Bond Ball Work Index kWh t Circuit Limitation Subika 22 to 28 15 to 17 SAG mill Apensu 33 to 38 15 to 22 ball mill Amoma 26 to 57 11 to 21 variable Awonsu 36 18 ball mill Oxide 76 10…

Online Optical Monitoring of the SAG Mill Chamber Sepúlveda Duarte 79 14 00 SAG and Ball Mill Online Ball Charge Level Measurement by Sound Churata 80 14 15 Teck s HVC Adaptive Cruise Control for Secondary Grinding Nuñez Hahn 81 14 30 Question Period 15 00 Break…

 · Before the Esperanza order FL s largest SAG mill measured 38 and its ball mills 26 To the average person the difference between a 38 and a 40 SAG Autogenous mills semi autogenous mills and ball mills for wet SAG and ball mill for gold ore grinding One of three SAG mills with 9 75 m diameter and 2 x 4000 kW drive power …

Ball Mills Steel Ball Mills Lined Ball Mills Particle size reduction of materials in a ball mill with the presence of metallic balls or other media dates back to the late 1800 s The basic construction of a ball mill is a cylindrical container with journals at its axis …

has experience of over 8 000 grinding mills globally including manufacturing and delivering the largest SAG AG mills in the world Our experts welcome the opportunity to assist you with circuit and circuit control design as well as start up operation and optimization of your mill …

and with the decreased grain size the necessary ball size also decreases Olejnik 2010 2011 For each grain size there is an optimal ball size Trumic et al 2007 The bigger ball in relation to the optimal one will have an excess energy and consequently the smaller ball mill has less energy necessary for grinding In both…

 · These mills are scheduled of start up on 2012 Our market share in China exceeds 80 with the largest mills supplied to date being a Ø7 9m x 13 6m 2x8 5MW Ball Mill and a Ø11m x 5 4m 2x8 5MW SAG Mill being the largest in China …

Depending on the mill size the SAG mills draws between 2 MW and 17 MW The product from the SAG mill is further reduced in size using pebble crushers and ball mills Hence typical gold or copper ore requires between 2 0 and 7 5 kWh per ton of energy to reduce the particle size …

autogenous SAG Mill via an utilized method Miduk copper concentrator is located in Kerman Province Iran and its size reduction stage includes one gyratory crusher which feeds one SAG mill 9 75 dia m 3 88 length m following two parallel ball mills 5dia m 7lenght m After SAG mill a…

The appropriateness of the transfer size in AG and SAG Mill Circuit Design SAG and ball mill circuits are used to show that Bond s equation does not hold over the particle size range −100 …

 · SAG mill make use of steel balls included with some large and hard rocks for grinding These mills utilize the balls in making the large fragments of materials broken into pieces The ball charge of a SAG mill is about 9 to 20 This process takes place inside the large rotating drum of SAG mill which is filled with balls partially …

SAG is an acronym for semi autogenous grinding SAG mills are autogenous mills that also use grinding balls like a ball mill A SAG mill is usually a primary or first stage grinder SAG mills use a ball charge of 8 to 21 The largest SAG mill is 42 12 8m in diameter powered by a 28 MW 38 000 HP motor …

around the secondary crusher a reduction in SAG mill make up media size to 105 mm and increased ball charge a reduction in SAG discharge screen size to 8 mm and smaller 65 mm ball mill make up media instead of the 80 65 mm blend The smaller SAG mill media size was recommended due to the wide range of conditions the mill…

Based on these test results a 6 7 m diameter × 2 1 m length SAG mill and a 3 3 m × 6 1 m ball mill were installed for commercial operation in closed circuit with a hydrocyclone The SAG mill had a 6–8 ball charge and the power consumption was 8 kWh t which agreed well …

Mills Technical Data The following technical data sheets show some of the standard Ball Mills and SAG Mills that we have available We can supply Ball Mills SAG Mills and other milling systems to your specific requirements given your particular technical specifications The selection and type of mill you require FAG SAG SABC rod or ball is at best difficult and depends on ultimately …

LG A mill power equation for SAG mills Minerals and Metallurgical Processing Feb 1990 pp57 62 Gross power No load power Net power drawn by the charge 8 13 The net power is calculated from Net power KD2 5L e c Watts 8 14 In equation 8 14 D is the diameter inside the mill liners and Le is the effective length of the mill including the …

Silicon conversions with the SAG Mill I was using flint in my play world so I made a test world and did a 64x64 run with 3 mills 1 with nothing one with flint and one with a dark ball The dark ball mill finished long before the others did the flint finished 6 stacks quicker than …

A SAG mill is generally used as a primary or first stage grinding solution Attrition between grinding balls and ore particles causes grinding of finer particles SAG mills are characterized by their large diameter and short length as compared to ball mills SAG mills are primarily used at gold copper and platinum mines with applications also …

Sagmilling com is home to a collection of both free and subscription based calculation tools to aid metallurgical process engineers perform comminution calculations Grinding circuit design tools including for SAG mill ball mill circuits and geometallurgy energy models are available to subscribers …

article osti 922135 title Improving Energy Efficiency Via Optimized Charge Motion and Slurry Flow in Plant Scale Sag Mills author Rajamani Raj K abstractNote A research team from the University of Utah is working to make inroads into saving energy in these SAG mills In 2003 Industries of the Future Program of the Department of Energy tasked the University of Utah team to …

Difference Between SAG Mill and Ball Mill from the working principle application structure etc Grind and blend solid or hard materials into smaller pieces by means of shear impact and compression …

3 SAG mill 8 – 15 ball charge Variable or moderate competency ore with the competency suiting the selected grind size Tarkwa Leinster Golden Pride Obatan Henty Fosterville Kittila Cosmos Cosmic Boy Jundee Tanjianshan 4 High ball charge SAG mill or ROM Ball mill 15 to 25 ball charge Low competency ore Hidden Valley Nzema Sepon …

Transfer Size T80 Is the 80 passing size of ore as it passes from the SAG mill to the ball mill It is typically about 1 3 the size of the screen opening but can be coarser than 1 3 especially when a pebble crusher is used Screening at 5 mm ensures that the T80 will be about 10 mesh 1 7 mm ensuring that the ball mill will work efficiently …

SAG MILL TESTING AN OVERVIEW OF THE TEST PROCEDURES AVAILABLE TO CHARACTERIZE ORE GRINDABILITY Bond Ball Mill 0 305 3 35 Any 0 149 10 5 Locked cycle Y Y Mod Bond 0 305 3 35 Any N A 2 1 2 Batch N Y Test Procedures to Characterize Ore Grindability …

The software uses the particular power model Bond Barratt Morrell Mi etc to determine what is the transfer size where the ratio of E SAG to E ball matches the ratio of mill power 1 1 5 in this example This is the maximum efficiency transfer size where the mills will both operate at full power …

The SAG mill product is then crushed to 100 passing 3 35 mm and is subjected to the Bond ball mill work index S d BWI grindability test to provide the total pinion energy at the specified grind size for mill design purposes herein reffered to as micro ore hardness The full SAGDesign test produces the SAG grindability W SDT and the Ball Mill…

Lets calculate select pick a new ball for your SAG mill Now lets suppose you have a SAG Mill and Ball Mill that are not drawing full kW Power The SAG Mill has a small circulation load of oversize given be the 3 8″ trommel screen and the 1 2″ x 1 1 4″ discharge grates The load of 4″ balls in this SAG is good but un measured SAG Ball consumption is average at 400 g …

Keywords Ball mills grinding circuit process control I Introduction Grinding in ball mills is an important technological process applied to reduce the size of particles which may have different nature and a wide diversity of physical mechanical and chemical characteristics Typical examples are the various ores minerals limestone etc …

The SAG Mill is a machine added by Ender IO It uses Micro Infinity µI to grind or mill items into their crushed variants like Ores into Dusts The SAG Mill has four output slots recipes can have 1 4 different outputs with different chances of obtaining those outputs Uniquely the SAG Mill can use Grinding Balls made from various materials to increase energy efficiency resulting in …

In multi stage ABC SABC circuits the AG or SAG mills are in closed circuit with screens and pebble crushers The mill discharge from these mills consists of slurry which goes to the ball mills for further grinding and coarse pebbles rocks which are crushed and sent back to the mill …

Fig 8 shows the optimum composition of the make up ball sizes for various feed sizes as a function of the size reduction ratio R Because mixtures of two balls 50 8 mm and 25 4 mm ball are always found to be optimum the results are plotted with the ordinate being the fraction of 50 8 mm balls …

 · Before making a change in the SAG mill ball size it is important to test it first in simulation …

The 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 …

Developments in SAG Mill Design and Operation Over the last few years SAG mill manufacturing technology has advanced rapidly The bounds of mill size have been pushed from two directions Firstly the advent of ring motors has removed the constraint applied by the power that a …

 · There are many other solutions however if the efficiency of a SAG mill is not what you are after all of the other options cost more in terms of maintenance and materials eg pure ball mills hammer mills and rod mills AG and SAG mills are cheap to operate and some inefficiency is …

Build up in critical size It is well established from the earliest use of AG and SAG mills that the build up of competent critical size material can drop throughput to half Morrell and Valery …

ball mill can be re organised as 7 and 8 where B Wio and A Wio are the corrected operating work indices and WAG SAG WBM are the respective power draw of AG SAG and ball mills Note 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…

With high aspect ratio SAG mills total charge to ball charge ratio should be greater than 2 up to 2 5 for a coarse mill feed say F80 110 mm If the mill feed size is fine say 50 mm or 30 mm then you are looking at a total charge to ball charge ratio of about 1 5 1 6 …

Single stage SAG Mills are very beneficial in reducing CAPEX for plants with a staged throughput approach When future tonnage is to be increased the SAG Mill can feed downstream ball milling to boost capacity Fuller Traylor SAG AG Mills range in size from 4 3m through 12 2m in diameter with powers as high as 28 000 kW …