calculate sag mill power draw

The article discusses the topic of the specific power consumption of a drum mill type SAG 8.5x5.3. The purpose of the study is to<br> determine the influence of some basic parameters like angular velocity of the mill drum, the wear on the drum's lining, mass of the mill filling, loading rate of the mill with ore and flow rate of incoming water of the …

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 ...

PFC3D can simulate the grinding media motion in the ball mill and calculate the power draw ... M., Morrison, R., 2006a. Prediction of slurry transport in SAG mills using SPH fluid fl ow in a ...

Development of an equation for tumbling charge and balls plus comparison to plant data suggests that the net mill power for cylindrical semiautogenous mills can be calculated from $${m_p} = 10.6{D^{2.5}}Lleft( {1 - 1.03J} right)left[ {left( {1 - {varepsilon _B}} right)left( {{rho _s}/{w_o}} right)J + 0.6{J_B}left( {{rho _b} - {rho _s}/{w_c}} …

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)

A further explanation is required to explain the importance of designing the SAG mill chamber to draw required power at optimum operating conditions of 75% critical speed and less than 30% by volume load. Recent studies in the three-foot diameter SAG mill are instructive. The following graph shows the relevant facts as Figure 2.

Grinding in AG mills is frequently assisted by steel balls, in which case it is called a Semi-Autogenous Grinding (SAG) mill. Semi-Autogenous Grinding mills came into operation in the mid 1970s [1

the mill shell. The measured power is 3,190 kW at mill shell, so the model predicts high by 298 kW, or 9%. However, by substituting the recommended 5% allowance for a cone end instead of Austin's cone allowance results in a 148 kW of power generated in the cone, for a total of 3,113 kW power draw at the mill shell. The measured power is 3,190 ...

A SAG mill operates with a 10,000 hp motor. Typical power draw is 80% of maximum. The 80 percent passing feed size to the mill is 6 inches and the mill discharge has an 80 percent passing size of 2.3 mm. Calculate the Operating Work Index for this mill if the feed tonnage rate is 1175 tonnes per hour. 2. A SAG mill operates with a 10,000 hp motor.

These equations are expanded to calculate the mass of the SAG mill contents and the proportion of steel media, ore, and water. 2. ... Power draw of grinding mills – Its measurement and prediction. In: 5th Mill operator's conference. Roxby Downs 16-20 October, 1994. Google Scholar. Mosher and Alexander, 2002. Mosher, J., …

Prediction of correct sag mill power consumption with a change in ore hardness, solid percent (density) to the sag feed, rpm of sag and PSD has always been very tricky. So far, I have used Austin-Morrell model and Hogg- Fuerstenau power model, but these models seem to work well only under certain boundary conditions.

The modeling and simulation of semiautogenous (SAG) mills have been widely used in the design and optimization of mill performance in terms of its power draw, processing capacity and product size distribution. However, these models are solved under steady approximation and do not provide any information on mill charge distribution in …

From that "power draw" you calculate a shell size from 4 parameters: diameter, effective length, wet or dry? %loaded and % of critical speed. ... On the other hand, for SAG mills with grate discharge, the charge level is a bit more variable, so you do sometimes see higher SAG mill power or mill load levels at higher circulating loads. This why ...

The Mill Filling Inference Tool which has been implemented at several mine sites, compares SAG mill load cell and power draw measurements with outputs of a semi-mechanistic power model to estimate ...

Scw = solid concentration by weight fraction in the SAG mill feed; Jb = balls charge (bulk fraction of the SAG mill volume); N/Nc = fraction of the SAG mill critical …

AG/SAG mill specific energy calculator ... It is therefore surprising that in all this time there have been no published models for predicting grinding mill power draw which have been validated ...

The Morrell C-model is generally regarded as one of the most accurate tumbling mill power-draw models and is ideally suited for this application of estimating fill levels of the SAG mill in real time.

The operation of AG/SAG mills is sensitive to mill filling, therefore developing grindcurves to relate mill filling to performance indicators such as throughput, power draw, and product size can ...

where m p is in kW; D is internal mill diameter (meters), L is internal mill length (meters); J is total fractional charge loading of the mill; J B is the fractional mill filling by balls; ε B is the effective porosity of the charge, taken as 0.3; ρ s and ρ b are true densities of rock and balls (tons per cubic meter), respectively; w c is ...

approach to modeling of mill power draw. Trans. Instn. Mining. Metall. (Sect C:Mineral Processing Extr Metall.) 105, January-April 1996 ppC54-C62. Austin 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 …

A case study of evaluating the variance of semi-autogenous (SAG) power draw in a grinding circuit is presented as well. Using Monte Carlo simulation showed that the mean power draw of the Sarcheshmeh SAG mill is about 9349.75 kW with a standard deviation of 983.2 kW, with the highest frequency occurring between 9058.5 and ...

Generic SAG mill geometry and operating conditions. SAG mills can have diameters up to 12.9 m. A three-dimensional slice of a generic intermediate size 8.4 m diameter SAG mill is used here. ... Mill power draw for …

The Bond model and Morrell E-model are employed as valid empirical models for predicting the power draw of ball mills and AG/SAG mills in industry, respectively. ... It should be noted that we used MAD of 24.62 regarding BSD 1 to calculate the dynamic voidage through Equation 19. Figure 11 illustrates the predicted mills' power draw …

Thus the power to drive the whole mill. = 49.5 + 66.0 = 115.5 h.p. = 86 kW. From the published data, the measured power to the motor terminals is 103 kW, and so the power demand of 86 kW by the mill leads to a combined efficiency of motor and transmission of 83%, which is reasonable.

In Fig. 3, Fig. 4 the data is presented in order to show the effect of the fresh feed size, particularly the % −6″ +1″ (−152 +25 mm), on the SAG mill power consumption (Pc) in kW and on the SAG mill specific energy consumption (Ecs) in kW h/t, obtained by dividing the power consumed (kW) by the fresh feed rate (t/h).

The chord produced by spacing equal to two times mill diameter (ft.) or 470 mm (18.8 in.) is desirable. Shell liners so designed can minimize charge "packing" problems and still provide sufficient lifts for normal mill action to lift the charge and hence draw power and do work (comminution). Mill end plate bolt spacing.

A nice and pretty online Ball Mill Power-draw Calculator was put live by one of the great prophets of grinding. comes ...

Larger than Ball mills at same power draw . Special Tumbling Mill Special tumbling mills [image: (135-6-14)] Conical Ball Mill. Wet or dry (air swept) Overflow or partial grate; ... in order to arrive the gross mill power. For all AG or SAG installations, batch lab tests are mandatory to determine whether this type of grinding is possible at ...

The ball load, at which the mill draws maximum power, is about 53%. The simulation results of 0.762-m mill running at 60% critical speed are plotted in Fig. 4. The relevant operating and simulation parameters are listed in Table 3. The calculated power draft is maximum at about 50% ball load.

SAG mill power draw models are used in mill design and grinding circuit modelling to predict how much power will be consumed by a particular mill geometry and operating …

The rod mill motor power is in horsepower at the mill pinion-shaft. For different length rod mills power varies directly as rod length. For difference between new and worn liners increase power draw by 6%, and adjust for bulk density per Table A. Wet grinding rod mills are normally used in minerals processing plants.

SAG/Ball Mill Sizing. Gross Power Draw and Specific Energy Calculator for Semi-Autogenous Grinding (SAG) and Ball Mills. Return to Mill Calculators.

This value corresponds to about 15% steel in the SAG mill and a load of about 35% and represents the motor power required and the shell is sized to suit that …

Data were collected from a wide range of wet industrial grinding mills to calibrate and verify the model. In total 76 data sets were generated covering the power draws of ball, SAG and AG mills in ...

The model development relating the charge shape and power consumption to the operating parameters of SAG mills and their usage in deciding on the mill operating strategies to calculate the wear of ...

bling mills (AG/SAG, rod, and ball mills) involved in reducing the size of the primary crusher product to that of the final product (usually the cyclone overflow of the last stage of grinding prior to flotation/leach-ing). 2. Feed rate to the circuit (dry tonnes/h) 3. Power draw of the comminution equipment (kW)

The fraction of mill volume occupied by rocks, grinding media and slurry in grinding mills are dominant factors influencing AG and SAG mill power draw and grinding rate.

The approximate horsepower HP of a mill can be calculated from the following equation: HP = (W) (C) (Sin a) (2π) (N)/ 33000. where: W = weight of charge. C = distance of centre of gravity or charge from centre of mill in feet. a = dynamic angle of repose of the charge. N = mill speed in RPM. HP = A x B x C x L. Where.

GROSS POWER CALCULATOR General . This model uses the equations from Morrell's 1993 PhD thesis: "The Prediction of Power Draw in Wet ... the model from grate to …

The general formula for sag calculation is as follows: Sag=h−h2−a2 . Where: Sag: This is the vertical distance between the lowest point of the cable and a straight line connecting its endpoints (measured in meters or feet). h: This is the height or elevation difference between the endpoints and the lowest point of the cable (measured in ...