SAG/Ball Mill
SAG/Ball Mill Sizing. Gross Power Draw and Specific Energy Calculator for Semi-Autogenous Grinding (SAG) and Ball Mills. Return to Mill Calculators.
Ball Charge and Grinding Efficiency
Ball feed size SAG mill water flow rate SAG mill power vs. wear geometry - maximizing kW-hr/ton & tons/hour in combination SAG mill liner change-out life/cycle vs. tons/kg consumed. Ball mill liner efficiency based on liner geometry and its influence on kW-hours/ton, total tons/life cycle, and P80 transfer to cyclones. Ball mill grind is based ...
Charge Motion inside a SAG Mill
The mill is a scaled-down replica of a commercial Koppers 6.1 m x 2.13 m (20 ft x 7 ft) SAG mill (see Fig. 1). The original design was developed by Vanderbeek and Herbst and was constructed by the Scale Model Makers of Cleveland, Tennessee. It is built of plexiglas and therefore allows the observation of the action inside the mill. The ...
SAG Mill | Autogenous and Semi-Autogenous Mills
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.
SAG vs. AG Mills: Understanding the Key Differences
SAG mills use a combination of steel balls and rock particles as grinding media, while AG mills use only the ore itself. Both types of mills are used for grinding ore in mineral processing operations, but SAG mills are larger in size and can grind larger quantities of ore. AG mills, on the other hand, are smaller and are typically used for ...
Ball Mills
CERAMIC LINED BALL MILL. Ball Mills can be supplied with either ceramic or rubber linings for wet or dry grinding, for continuous or batch type operation, in sizes from 15″ x 21″ to 8′ x 12′. High density ceramic linings of uniform hardness male possible thinner linings and greater and more effective grinding volume.
Operation Analysis of a SAG Mill under Different …
the fill level ratio, and the steel ball ratio on the SAG mill. Finally, through statistics and analysis of particle information and mill power under different conditions, we analyzed the influence of three parameters on the particle fracture effect in the SAG mill and obtained the best operating parameters of the SAG mill. 2.
Ball charges calculators
Mining Area. Links and Contact. - Ball charges: This calculator gives the surface and the average weight of the ball charges. It gives also a rough interpretation of the ball charge efficiency: - Ball top size (bond formula): calculation of the top size grinding media (balls or cylpebs): - Modification of the Ball Charge: This calculator ...
STARTLING EFFECT OF BALL SCATS REMOVAL ON …
NAVACHAB CIRCUIT. The circuit consists of a single-stage, low aspect ratio (diameter:length = 0.5) mill, typical of the majority of SAG mills in the South African gold mining industry. These are locally known as run-of-mine, RoM, mills. The mill is operated at 90% of critical speed and with a volumetric load of 40%.
Methods to Estimate AG/SAG Mill Power Requirements
A linkedin group was recently discussing this by asking: I've tried to estimate AG/SAG Mill power requirements using several different methods: (1) Using the results of SMC data. (2) Using SAG Power Index (SPI) data. (3) Using the 1989 Barratt method updated on Alex Doll's Web site (February 16, 2015)
What's the Difference Between SAG Mill and …
The biggest characteristic of the sag mill is that the crushing ratio is large. The particle size of the materials to be ground is 300 ~ 400mm, sometimes even larger, and the minimum particle size of the …
An improved method for grinding mill filling
The new method offers engineers and researchers a safer and faster method for quantifying the filling level in industrial SAG and ball mills, and allows the surface …
An improved method for grinding mill filling
1. Introduction. Mill filling has a dominant effect on grinding mill performance (Apelt, Asprey and Thornhill, 2001), and therefore, its accurate measurement is vital for modelling grinding mill performance.Measuring filling is also necessary to estimate the composition of the load for mill modelling: rock and slurry for AG mills; rock, balls and …
Ball Charge and Grinding Efficiency
SAG mill optimization to feed ball mill optimized P80. Most SAG mill are not optimized for the combined SAG & Ball mill throughput such as: SAG & Ball mill % ball content SAG …
Choosing a SAG Mill to Achieve Design Performance
It is an approximation or a best guess based on limited data. This equation is: y = 225 – 1.94 x (1) Where x = the load in the mill expressed as measured % by volume and y = kg/h of feed. This information is based on observed throughput reductions caused by loading the 3-ft. SAG mill to over 26% by volume.
(PDF) Operation Analysis of a SAG Mill under …
In order to obtain the optimal operation parameters of a SAG mill, in this paper, the discrete element method (DEM) is used to simulate the breakage process of …
Monitoring the fill level of a ball mill using vibration sensing …
Ball mills are extensively used in the size reduction process of different ores and minerals. The fill level inside a ball mill is a crucial parameter which needs to be monitored regularly for optimal operation of the ball mill. In this paper, a vibration monitoring-based method is proposed and tested for estimating the fill level inside a …
A comparison of SAG mill power models
Gross power = 265 + 1.26 × (2,233 + 215) = 3,349 kW. The conversion between motor input (gross) power and mill shell power, described earlier, is 0.931. Therefore, the predicted power at the mill shell is 3,119 kW, which is 71 kW less than the measured shell power (3,190 kW), a difference of 2%.
Operation Analysis of a SAG Mill under Different …
In order to obtain the optimal operation parameters of a SAG mill, in this paper, the discrete element method (DEM) is used to simulate the breakage process of the particles by controlling three parameters, i.e., the mill speed ratio, the mill fill level ratio, and the steel ball ratio. This method simulates the particles size, mill power, and ...
Variable Speed SAG Mill
The second step to decreasing high wear rates was to reduce the maximum operating speed on the SAG mill from 13.2 RPM (78% of critical speed) to 12.7 RPM (75% of critical speed). Justifications were made for the installation of an Omnicone crusher on the SAG pebble oversize material. Conservative estimates were made that as little as a …
Research on performance of a laboratory-scale SAG mill …
Mishra and Rajamani [[2], [3], [4]] first studied the charging behavior and the rule of energy consumption of the ball mill based on 2D DEM in 1992. Cleary et al. [5] studied the effect of ball mill rotational rate on charge behavior and mill power, and in 2001, Cleary et al. [6] first applied 3D DEM to calculate the operating power of a SAG mill.
How Mill Load/Charge is Estimated
Sag mills in the gold and copper operations would vary from 6%- 15% and are normally grate discharge types in most cases the densities of the slurry in the mill is over 65% and that goes for ball mills also. Off course you have a upper limit or the balls will "float" out. Higher densities allow better grind and increase residence time in the mill.
calculating steel ball level in sag mill
calculating steel ball level in sag mill. Webeffects of end mill length to depth of cut that is if shortening stickout by 1/3 does end mill depth of cut increase by 3x39 or 3x3x327 1/2 HSS end mill 2 stickout max recommended DOC in 1018 Steel x 9 x 27 so if to 3rd power with end mill stickout you can take a DOC if it stuck out that far .
calculating steel ball level in sag mill
Current operational results show that the SAG mill is operating at 5% ball charge level by volume and is delivering a K80 800 micron product as predicted. Power drawn at the pinion is 448 kW, 13.617 kWh/tonne (SAG mill) and 570 kW, 17.325 kWh/tonne (ball mill) when processing 32.9 mtph, for a total of 30.942 kWh/tonne or 14.6% above the ...
Energies | Free Full-Text | Operation Analysis of a …
In this paper, the optimal fracture parameters of the SAG mill are 80% rotation rate, 15% fill level ratio, and 14% steel ball ratio, and through subsequent simulation experiments, the steel ball ratio of the …
Choosing a SAG Mill to Achieve Design Performance
It is an approximation or a best guess based on limited data. This equation is: y = 225 – 1.94 x (1) Where x = the load in the mill expressed as measured % by volume …
Calculate a Mill's Operating Work Index
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, …
AG
Current operational results show that the SAG mill is operating at 5% ball charge level by volume and is delivering a K80 800 micron product as predicted. Power drawn at the pinion is 448 kW, 13.617 kWh/tonne (SAG mill) and 570 kW, 17.325 kWh/tonne (ball mill) when processing 32.9 mtph, for a total of 30.942 kWh/tonne or …
An improved method for grinding mill filling
The new method offers engineers and researchers a safer and faster method for quantifying the filling level in industrial SAG and ball mills, and allows the surface profile to be surveyed, without requiring the contents to be level. ... a complete grind-out to quantify the volume of steel balls contained in the mill. While the mill contents can ...
The Selection and Design of Mill Liners
Greatly accelerated liner wear due to high-energy impacts on the liner. For a 5m diameter mill these will be in excess of 8m.s-1, for a 10m diameter mill these exceed 12m.s-1. This causes high chrome liners to spall and crack and they may even fracture. This can reduce liner life from a year to less than a few months.