sag mill ball charge

Modelling SAG milling power and specific energy ...

The ball charge is a function of the bulk fraction of the SAG mill volume (Jb) occupied by balls; the ore retained in the mill is the result of the volumetric filling which depends on the ore size distribution (specially the % +6″ and the % −6″ +1″), on the rotational speed (N/Nc) and on the solid concentration by weight fraction inside ...


Mill drives: the desire for increased power and the ...

mill speed and shell liner/lifter simulations and, particularly, ball charge volume and ball top size, both of which are dependent upon the contingency applied to the transfer size in the SAG circuit product. Iterations of these para-meters can be performed in some models (e.g., DJB's "Reduced Recovery" and "Millpower2000") to determine


SciELO - Brasil - Modelling and Simulation of the Santa ...

The modifications included (a) increasing the SAG mill ball charge from current 8% to 12%, as well as (b) reducing the cyclone pulp feed density for the achievement of the stipulated cut size. Such a combination was due to the fact that when increasing the SAG mill ball charge, it grinds coarser, and by reducing the cyclone feed percent solids ...


C O N S U L T I N G L T D TECHNICAL MEMORANDUM

The value T80 is the "synthetic" transfer size between the SAG mill and ball mill – a fines-corrected 80% passing size 2 of the SAG mill product (or the combined SAG mill product and crushed pebbles if the circuit is sending crushed pebbles to …


mining ore sag mill and ball mill

What is the difference between a SAG mill and ball mill? SAG mills use a ball charge of 8 to 21%. [6] [7] The largest SAG mill is 42′ (12.8m) in diameter, powered by a 28 MW (38,000 HP) motor. [8] A SAG mill with a 44′ (13.4m) diameter and a power of 35 MW (47,000 HP) has been designed. [9] Attrition between grinding balls and ore . More


The Effect of the Grinding Charge Trajectory on the ...

and optimal grinding charge trajectory for the SAG, Ball and Rod Mills. • Identified potential benefits could be obtained with an ideal grinding media charge, mill speed as well as optimisation of lifter profile (specialty lifter face 20 angle) which is directly related with mill power draw, internal motion of mill charge,


Difference Between Sag Mill vs Ball Mill - mech4study

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. Interior of the drum uses the lifting plates. These plates inside the drum are responsible for picking the grinding material up to fall down again throughout the rotations.


AN OVERVIEW OF SINGLE STAGE AUTOGENOUS AND …

charge) Incompetent ore 5 Low ball charge SAG mill, high mill speed. (4% ball charge, 90% Nc) A cross between AG and SAG for competent, abrasive ores. As typically operated in RSA. 6 SAG mill (configurations 3, and 5 ) with recycle crusher Competent ores, better suited to coarse grind sizes as circulating loads can be high 7 SAG mills treating ...


ME Elecmetal Grinding Apps - ME Elecmetal · Global ...

SAG mills • Determination of your SAG mill's power draw characteristics. • SAG Mill Steel Charge Estimation tool provides an estimate of the percent steel in the charge of your SAG mill based on the power draw and the total charge volume. • Ball impact energy chart to determine the impact energy of balls as a function of mill diameters.


A Method to Determine the Ball Filling, in Miduk Copper ...

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 …


Mill Charge - an overview | ScienceDirect Topics

SAG mills of comparable size but containing say 10% ball charge (in addition to the rocks), normally, operate between 70 and 75% of the critical speed. Dry Aerofall mills are run at about 85% of the critical speed. The breakage of particles depends on the speed of rotation.


AMIT 135: Lesson 6 Grinding Circuit – Mining Mill Operator ...

Grinding media is grinding feed plus 4-12% ball charge (ball dia.100- 125 mm) High capacity (short retention time) Less sensitive to feed composition (critical size material) Semi-Autogenous Mill Note the size of the mill: Why does the diameter need to be so big? [image: (135-6-2)] SAG Mill Circuit Example — Gold Processing


calculates the grinding charge of a ball mill | Mining ...

mill charge and speed. SAG Mill product P80 values are typically in the range of … OPTIMIZING SAG MILL PRODUCT SIZE IN SAG MILL _ BALL MILL GRINDING CIRCUITS


SAG Mill - Official Feed The Beast Wiki

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 …


Mill Steel Charge Volume Calculation

% Steel Charge Loading in Mill = 113 – 126 H/ D . Ball Mill Charge Volume Calculation. Charge Volume of a Grinding Mill (Method 1) Charge Volume of a Grinding Mill (Method 2) Process Machinery Reference Manual. by David Michaud May 13, 2021 June 19, 2015 Categories Tools of a Metallurgist Post navigation.


How does a ball mill function? – Swirlzcupcakes

The starting point for ball mill media and solids charging generally starts as follows: 50% media charge. Assuming 26% void space between spherical balls (non-spherical, irregularly shaped and mixed-size media will increase or decrease the free space) 50% x 26% = 13% free space.


Small-Scale Continuous SAG Testing Using the Macpherson ...

The mill charge PSA is compared to that of the feed to identify any coarse build-up. The size-by-size density of the rocks constituting the mill charge is also measured, as it can be significantly different from the feed, which could affect the power draw predictions, especially in fully autogenous or low ball charge applications. The mill charge


Paper # 25 - Copper Mountain Overview on the Grinding ...

Table 2 and 3 include the process and operating data for the Copper Mountain SAG mill. Table 2 - general SAG mill circuit and ore data Specification Data Operating circuit Closed-circuit Operating mill ball charge 15 percent by volume Operating mill total charge 32 percent by volume Mill speed 10.08 RPM (76 percent of critical speed average)


What's the difference of Ball mill, SAG mill, AG mill?

Attrition mill is a type of grinding mill by kinds of media to crush lump to powder-like substances. 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 Grinding (SAG) mills, balls of various sizes in Ball Mills and less commonly these days, steel rods in Rod Mills.


PERI™ AutoCharge Mill Grinding Ball Charging System

Our PERI AutoCharge Mill Grinding Ball Charging System is designed to provide a controlled continuous supply of balls to maintain consistent ball loading in the grinding mill. Continuously charging grinding balls will allow your mill to maintain a consistent power draft, charge volume, ore feed rate, or consumption average (kg/t).


MillScanner™ - WordPress

ear for the mill and has the ability to accurately detect ball-to-liner impact occurrences. By quantifying the charge toe angle, or the media angle (β dynamic ), on each rotation, a precise control strategy based on the internal dynamics and volumetric loading of …


What's the Difference Between Ball Mill, Rod Mill and SAG ...

Ball 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 ...


between sag mill weight and power

The power draw of the SAG mill has room for significant improvement. As ball filling in the SAG mill is quite low, additional grinding media would likely increase the processing capacity of the SAG mill; however, the capacity of the ball mill, with installed power for the required product size of 170 µm, has reached its limit.


The influence of mill speed and pulp density on the ...

The pilot mill is also equipped with a sensor measuring the 'ball and pulp toe and shoulder angles' (see Figure 3). These data are then used to calculate the total pulp and ball charge angle (see Graph 5). Graph 5 clearly illustrates how the ball charge stays quite compact till about 73% solids as the total media angle does not change.


Online SAG Mill Pluse Measurement and Optimization ...

@article{osti_969329, title = {Online SAG Mill Pluse Measurement and Optimization}, author = {Rajamani, Raj and Delgadillo, Jose and Duriseti, Vishal}, abstractNote = {The grinding efficiency of semi autogenous milling or ball milling depends on the tumbling motion of the total charge within the mill. Utilization of this tumbling motion for efficient breakage of …


SAG Mill | Autogenous and Semi-Autogenous Mills | FL

Since the early 1980s, we have been designing and manufacturing Semi Autogenous Mill (SAG Mill) and Autogenous Mill (AG Mill) under the Fuller-Traylor brand. Semi-autogenous grinding uses a minimal ball charge in the range of 6-15% while autogenous grinding uses ore only. SAG and AG Mills operate by lifting ore/grinding media and dropping it on ...


Keeping an eye out for grinding mill dropped charge and ...

For example, a large 24 foot (7.3 m) diameter ball mill charge typically weighs around 2 million lbs (907 tons). Even though Semi Autogenous Grinding (SAG) and Autogenous Grinding (AG) mill charges contains less balls and no steel balls respectively, their large mill volumes can become quite heavy as well.


STARTLING EFFECT OF BALL SCATS REMOVAL ON SAG MILL …

IV-126 Figure 1 The mill interior and details of the discharge grate Figure 2 Ball scats IV-127 Evidence of Excess Scats Mill charge When inspecting the …


SAG/AG SCU - Millwatch

CHARGE LEVEL. Maintaining an optimum charge in a SAG mill remains one of the fundamentals for efficient mill processing. If the charge level or the ball to charge ratio is incorrect, breaking liners and/or increasing power consumption is inevitable and can only result in degraded mill efficiency.


SAG mill ball charge determination and its influence on ...

In semi-autogenous grinding (SAG), the grinding mill inventory, (i.e. volume of total charge, volume of ball charge, etc.) is important in determining the optimum operating condition for maximum production (tph), minimum specific energy (kwh/t) or lowest cost ($/t).