Paper held at SAG Conference 2011 - By S. Gaulocher (ABB), K.S. Stadler (ABB), Th. von Hoff (ABB), R. Veldsman (ABB), A. Fuerst (ABB) and J. Koponen (ABB): Gearless mill drives (GMDs) are the workhorse in the mineral processing industries, more specifically when it comes to grinding crushed ore and cement (in various production stages) in semiautogenous (SAG) …
SAG mills generate higher levels of impact reduction and ball mills higher levels of abrading action. A mill lining system serves two purposes: to protect the mill shell from wear caused by the impact and abrasion of the mill charge, and to elevate and tumble the mill contents in the necessary manner to create a grinding action.
mill. As such, primary ball mills should be designed with the rod mill work index, and single-stage ball mills should be with both the rod mill and ball mill indices. This is because it is common to observe a difference (sometimes significant) between the rod mill and ball mill index values for a given ore type (McKen, Verret, & Williams, 2006). On
Mills - SAG Mills and Ball Mills - Asias Resource Connections. 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..
At present, the removal of the bolts which fasten the liners should be carried out manually as part of the maintenance procedure SAG mills should be subjected to. The disadvantage of this procedure is the fact it should be carried out manually which makes the system to lose efficiency due to the high maintenance periods. Due to the above, a robot system and method have …
Optimisation of the Cadia Hill SAG mill circuit PDF Download . Oct 21 2015 SAG Mill I12 Ø Effect of SAG Mill Feed Size Distribution and Ore Variability Ø Mill liner design modifiions and Ø Circuit Design Considerations The effect was consistent with 70mm 90mm and 80mm grate apertures no matter what the theoretical 39open area shell liner life mill load operating Oct 21 …
crushed ore is fed into a SAG/Ball mill circuit with a median size of approximately 12,000 microns. Most SAG Mills are operated in closed circuit with a screen. The screen fi lters undersized ore, normally minus ½ inch, to a ball mill discharge sump. The combined mill discharg-es are pumped to undergo classifi cation, normally via hydrocyclones.
There are two lines consisting of this SAG - ball mill combination where the SAGs are denoted as SAG1 and SAG2. Note: Each SAG mill is operated in a closed circuit manner in conjunction with a typical trommel screen and pebble crushing circuit. The ball mills are also operated in a closed circuit employing two hydrocyclone separators. The
B = ball size (inch) If a power loss was in deed occurring in the manner indicated above, then. given a typical ball size of 65mm (2.5inch), such power loss would only. be noticeable in …
Antamina Compania Minera Antamina S.A. Peru Project: One SAG Mill and 3 Ball Mill Drive Systems Capacity: SAG Mill 1000 t/h Ball Mills 1000 t/h Consultant: Bechtel, USA Mill Builder: FFE Minerals, USA Mill Size: SAG Mill 38 feet/11,58 m Ball Mills 24 feet/7,32 m Ore processed: Copper/Zinc Drive Rating: SAG Mill 20,1 MW, 9,23 rpm Ball Mills 11,2 MW, 11,38 rpm
mills in the older plants that had many mills in parallel. In fact this is generally still the case in the multi-stream plants, where mill liner design and selection is only tackled on a cost consumables basis. However, the gains to be had through good liner design and selection are just as great as on the large SAG mills.
The mill building was energized with a temporary 25kV power line, which enabled interior and exterior lighting and also the use of critical components such as the overhead crane. The foundations for the Ball and SAG mills were prepared with concrete and grout works, as well as anchor bolt and sole plate installation.
The specific energies of the SAG and ball mills were determined using AusGrind (Ausenco's in-house software) (Lane, Foggiatto, Bueno and McLean, 2013 and Morrell's ) method. SAG mill specific energy was a function of the inverse of the Axb value, the mill geometry and the mill operating conditions.
In a SAG mill the dimensions of the mill were 9.75. m × 3.5 m and the specific gravities of the mineral and that of the balls charged were 4.1 and 7.9 respectively.. The mill was rotated at 75% of its critical speed when 8 % of the mill volume was charged with grinding balls.Estimate:1. The mill power drawn, 2. The maximum mill filling possible.
GDM include autogenous (ag), semiautogenous (sag) The ideal slurry flow in a typical grate discharge mill is and grate discharge ball mills. The purpose of the pulp schematically shown in Fig. 1. lifters is simply to transport the slurry passing through The geometry of conventional pulp lifters is such that the grate holes into the discharge ...
MILL LINERS. Bradken is a leading supplier of high quality Mill Liner Systems to suit AG/SAG, Ball and Rod Mills. By utilising the latest technologies, we aim to provide customers with an advanced Mill Liner System that increases mill performance and availability. The optimised design of Bradken's range of Liner Systems offers a number of ...
SAG mills have a power higher than 10 MW. Even ball mills have a power larger than 10 MW. For this reason, they have an important impact in energy consumption and in the operation of the power distribution system. Figure 1. Picture of a typical GMD system for a SAG mill Figure 2 presents the power circuit of a cycloconverter fed synchronous motor.
system, primary mills and secondary mills. In the second generation, SAG mills re-placed the second and third stages of the crushing system and also the primary mills. Example configuration for the second generation. SAG and ball mill for the …
A deeper understanding of the milling operation of ball mills helps mineral processing engineers to control and optimize them, and therefore, reduce their consuming power. In this work, the milling operation of ball mills is investigated using two methods, i.e. DEM and combined DEM-SPH. First, a pilot scale ball mill with no lifter is simulated by both methods.
Ball mill and sag mill girth gear, trunnion head. Both the ball mill and the sag mill can process non-metals, ferrous metals, non-ferrous metals, rare metals, etc., and are divided into dry and wet types to meet the needs of various materials. The structure of the ball mill and sag mill is similar.
The standard method for sizing secondary ball mills (usually the overflow type) in AG/SAG circuits follows published mill supplier information with aspect ratios in the range 1:1.5 to 1:2.0, depending upon product sizing and pulp flow, i.e., the highest expected circulating loads (Morrell, 2001). The applied net power, calculated from testwork
ball mills, but also from our comprehensive scope of services, ranging from maintenance and OEM spares procurement to the optimization of existing plants. The grinding unit most commonly used for grinding brittle materials, such as cement, is still the ball-filled ball mill.
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 ...
and 2100 µm, respectively. The value T80 is the "synthetic" transfer size between the SAG mill and ball mill – a fines-corrected 80% passing size2 of the SAG mill product (or the combined SAG mill product and crushed pebbles if the circuit is sending crushed pebbles to the ball mill circuit, a.k.a. SABC-B operation). The EF4RM for
PJV is running the SAG mills at approximately a 12% ball charge and the ball milling circuit is The purpose of the "Mine-to-Mill" project was to determine the impact of not often constrained. blasting on SAG mill feed size distribution and hence mill throughput.
The ball mill accepts the SAG or AG mill product. Ball mills give a controlled final grind and produce flotation feed of a uniform size. Ball mills tumble iron or steel balls with the ore. The balls are initially 5–10 cm diameter but gradually wear away as grinding of the ore proceeds. The feed to ball mills (dry basis) is typically 75 vol ...
circuit. The Kinross Paracatu new grinding circ uit consists of one 11.6 x 6.7m (38' x 22') SAG mill with. installed po wer of 20MW, followed by two 7.3 x 12.2m (24' x 40') ball mills with ...
PDF | On Jan 1, 2011, A. Mainza and others published RoM Ball mills - a comparison with AG/SAG milling | Find, read and cite all the research you need on ResearchGate
B = ball size (inch) If a power loss was in deed occurring in the manner indicated above, then. given a typical ball size of 65mm (2.5inch), such power loss would only. be noticeable in …
Grinding in ball mills is an important technological process applied to reduce the. size of particles which may have different nature and a …