the mill power and the efficiency of the mill operation (Van Nierop and Moys, 2001). If a SAG mill has been designed with a conventional power or specific energy model which do not con-sider the projected feed size distribution it is likely that this mill will reach the expected power .
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.
Jan 01, 2016· 9.4. AG/SAG Mill Power. In designing crushing–grinding flow sheets, correct estimations of mill power draw are important as it serves as one of the deciding factors for selecting an option between AG/SAG mills. In most cases, the circuit with the least or optimal power consumption is the preferred choice.
product fractions, specific power draw, and mill performance. Therein, load density and ball filling percentage in semi-autogenous mill and its effect on the mills power draw is of great value. There exist several ways to calculating ball filling such as drawing out whole internal mill .
The SAG Power Index (SPI) test (Starkey & Dobby, 1996) uses a benchscale SAG mill test to - determine the specific energy of an industrial SAG mill. The test is operated in closed circuit and the time required to grind the material to a P 80 of 1.7 mm is used to predict AG/SAG .
The mill critical speed will be calculated based on the diameter (above) less twice this shell liner width. Mill Actual RPM: Enter the measured mill rotation in revolutions per minute. Result #1: This mill would need to spin at RPM to be at critical speed.
Decision-making on selection of SAG mills increasingly uses the methods of sizing the milling power based on laboratory tests on grindability of minerals. This article considers one of such methods allowing determination of mill characteristics based on the Bond work indexes of .
Mill Power Draw Models. The mill power draw models are used to predict how much power will be consumed by a particular type of mill, mill geometry and set of mill operating conditions. This power is transferred to the ore and used to predict the throughput when combined with the specific energy consumption models.
May 24, 2018· A circuit breaker is essential for making circuits safe and minimizing possibilities of fires or electric shocks. But unless you have your circuit breaker sized correctly, your safety will not be ensured. The calculations in order to choose the right size are fairly simple and could save lives.
Mar 14, 2018· Divide the watts of a given electrical item by the total number of volts available from the electric outlet to calculate amperage draw. The amount of current flowing through the wire is measured in amperes, or amps. The equivalent of available electricity at the power source is voltage, or volts.
ball mill specific energy calculator xls. ball mill specific energy calculate Gold Ore Crusher. 2012828 Calculation of the power draw of dry multicompartment ball mills 229 In order to design a ball mill and to calculate the specific energy o Get Price how to calculate the energy consumption of a ball mill. Get Price Or Chat Online
Part 1 of this two-part contribution presented a mathematical model, based on the dynamics of the charge and termed the 'C-model', for prediction of the power draw of tumbling mills.
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.
Dec 12, 2016· If P is less than 80% passing 70 microns, power consumption will be. Ball Mill Power Calculation Example. A wet grinding ball mill in closed circuit is to .
Decision-making on selection of SAG mills increasingly uses the methods of sizing the milling power based on laboratory tests on grindability of minerals. This article considers one of such methods allowing determination of mill characteristics based on the Bond work indexes of .
Power Draw Of Wet Tumbling Mills And Its Relationship To Charge Dynamics - Part 1 A Continuum Approach To Mathematical Modelling Of Mill Power Draw Power Modelling Of Stirred Mills Predicting The Overall Specifcie Energy Requirements Of AG SAG Ball Mill And HPGR Circuits On The Basis Of Small Scale Laboratory Ore Characterisation Tests
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 credit for the fraction of the material that had been already ground to final product (Q1). To calculate .
of the energy required by a SAG mill. Put another way, the SAG mill energy required according to this statement, is 2.5 times more than the Ab value to produce the same degree of particle breakage. There is a speci fi c gravity factor that affects AG/SAG power draw. The lighter material, in the 2.5 specifi c .
Sta ndardize feed and product sizes are used to calculate the ... 32 100 Continuous / Yes AG / SAG mills SAG Power Index (SPI) (Starkey and Dobby, 1996) 19 5 Batch / No AG / SAG mills Lab HPGR ...
Mill Power Draw. The motor power draw required to turn a mill from rest to the operating speed includes the energy required for the initial starting torque and mechanical arrangements to rotate the mill. It is generally accepted that practical mill power (PM ) is a function of mill capacity and diameter, i.e.,P M = Mill Constant * (Mill ...
2. 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.
Jan 26, 2007· Easy DIY Power Drawbar for Milling Machines (Bridgeport / R8 / Kurt Style) Here's the power drawbar perched atop my Industrial Hobbies Mill. Click this image for a MOVie file of the power drawbar in operation: Requires QuickTime! I don't know how I got by without one, now that I have it.
Ball mill power draw predicted from the Denver slide rule, kW 0 200 400 600 Calculated ball-mill power draw from the m odel derived, kW Data compared Line y=x Fig. 2. Comparison of the ball mill power draw from the Denver slide rule and the proposed model. Dashed line corresponds to y=x.
Oct 24, 2018· To calculate the operating work index of a circuit, you must measure four things: P: The power draw of the mill. This is usually calculated from the input leads to the motor, then multiplied by ...