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 ...
WhatsApp: +86 18838072829Ball mills in HPGRBall mill circuits tend to have more installed capacity than their counterparts in AG/SAGBall mill circuits. This is because the product size distribution from AG/SAG mills tends to have more fine material than the HPGR circuit product ( Morrell, 2009, Morrell, S., 2011 ) and hence need less ball mill power.
WhatsApp: +86 18838072829SAG / Ball Mill Monitoring. Condition Monitoring to Ensure Reliability for Critical Grinding Equipment in Mining . Today's mining operations must keep crucial milling assets online and running optimally, but variations in ore particle size, feed rate and moisture content, can lead to plugging, high vibration and machine bearing wear, and ...
WhatsApp: +86 18838072829The right determine of SAG feed size. This depends on the mill diameter and the ball size. Feed size necessary to take 80% of the maximum piece of ore that will crushed by the balls. For the big SAG more than 8 meters optimal feed size will be 50mm. Ball size 120 ... 125mm. Do not a pebble crushing, the need secondary crushing.
WhatsApp: +86 18838072829In a SAG mill the dimensions of the mill were m × m and the specific gravities of the mineral and that of the balls charged were and respectively.. The mill was rotated at 75% of its critical speed when 8 % of the mill volume was charged with grinding :1. The mill power drawn, 2. The maximum mill filling possible.
WhatsApp: +86 18838072829SAG mill throughput versus feed size. Reprinted from Scotia Bank (2014b). ... • the use of a blend of ball mill balls to increase finer size particles and smaller cyclone apex.
WhatsApp: +86 18838072829Figure 1 SAG mill compared to crusher and ball mill product size distributions (Powell et al 2014) The evaluation of the SAG mill perform ance with P80 value s in a Bond work inde x calculation
WhatsApp: +86 18838072829Depending 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 and kWh per ton of energy to reduce the particle size. Considering a typical mining operation processes 10,000 to 100,000 ...
WhatsApp: +86 18838072829the SAG mill or Ball mill in the range of SAG product size adjustments from mm to mm. The SAG mill transfer size T80 can be adjusted using the Bond Work Index, for product sizes coarser or finer than the basic SAG product (T80) of mm. More specifically, in the T80 range of to mm,
WhatsApp: +86 18838072829In order to eliminate the impact of the accumulation of rock, the autogenous mill allows to add about 3% of the ball (Φ80 ~ Φ120), SAG mill steel ball filling is generally 8% ~ 12%, even up to 15%.
WhatsApp: +86 18838072829The ball size distribution used in the SAG mill tests is presented in Table 2. The one designated as "standard" was used in nearly all SAG tests, whereas the one identified as "finer" was used for a particular test involving the JAN sample. ... Increased SAG mill ball charge from 4 to 16% resulted in only a modest increase in circuit ...
WhatsApp: +86 18838072829SAG mill drive systems used on the same size grinding mill: ... ball mills, 18x27 drive with an air clutch. motor, 602,000 6050 D Primary SAG, 34x1 6 Two vafiable speed dc motors coupled mill, 4 million 22,500 to a gear drive with air clutches. motor, million each 6000
WhatsApp: +86 18838072829Based on his work, this formula can be derived for ball diameter sizing and selection: Dm <= 6 (log dk) * d^ where D m = the diameter of the singlesized balls in = the diameter of the largest chunks of ore in the mill feed in mm. dk = the P90 or fineness of the finished product in microns (um)with this the finished product is ...
WhatsApp: +86 18838072829AG/SAG/Ball Mill Sizing Gross Power Draw and Specific Energy Calculator for Autogenous Grinding (AG), SemiAutogenous Grinding (SAG) and Ball Mills. Exit Mill Calculator ... Ball Top Size / Refill Size: [mm] Mill Power Draw Available Mechanical. Description. Value Units. Power Draw Model Morrell [kW] Metallurgical Power Requirements
WhatsApp: +86 18838072829same conditions apply in sag mills. However, in this case the required balance between coarse and intermediate size rocks is different to that for ag mills. This is because the steel balls in the sag mill do the duty of the larger rocks. As a result the more balls that are loaded into the sag mill the fewer larger rocks are required.
WhatsApp: +86 18838072829The final plan was to increase the ball charge in the SAG and ball mill to 10% v / v and 27% v / v, respectively; set the upper limit of the operating power in the ball mill to 5800 kW; use a TRIO TC Series crusher (without a power/feed ratecontrolling device, but with a feed bin) to crush pebbles for recirculation back to the SAG mill feed ...
WhatsApp: +86 18838072829At the end of 2010, the SAG mill ball size was changed to 10mm but pro5 ved to be unsuccessful, with the mill becoming unstable due to insufficient ball charge and a feed topsize of between 38 mm and 50 mm. A blend of 125/105 mm media was used from December 2010 until March 2011 when the 125 mm
WhatsApp: +86 18838072829Figures 4a and 4b are for the same size mill with a ball charge of 6% of mill volume (290 lbs. per cubic foot). ... 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, kWh/tonne (SAG mill) and 570 kW ...
WhatsApp: +86 18838072829The results of ball mill grinding tests are shown in Figure 6. Figure 6a,d show the effect of grinding time on the particle size composition of the raw ore and pebbles, respectively. As expected, the grindability of the raw ore was stronger than that of the pebbles in the ball mill, although this distinction was less obvious as in the abrasion ...
WhatsApp: +86 18838072829SAG Ball mill % ball content SAG % ore content SAG grate size and end mill design including grate geometry, location, shape, pan cavity, recycle % in pan cavity, et. al. SAG lifter and end cone geometry can change SAG mill performance more than 20%50% depending on P80 transfer size and Axb, some of which is published and some will be ...
WhatsApp: +86 18838072829of the 39th Annual Canadian Mineral Processors Conference 2007 125 The SAG mill is 26' diameter x 12'3" EGL and powered by 4,500 HP motor driven by a variable speed LCI drive that can control the mill speed from 36% to 80% of critical speed depending on ore type and operational demands. Ball charge is typically 812% and is adjusted accordingly after monthly mill ...
WhatsApp: +86 18838072829operation of SAG mills. SAG mills are currently the technology of choice in hard rock milling operations for reducing primarycrushed ore to ball mill feed. In recent years, the trend has been towards largersized SAG mills with diameters of m (34 ft) and above, with the largest being m (40 ft) in diameter and drawing 20 to 22 MW ...
WhatsApp: +86 18838072829The particle size should not greater than 350mm. 3. The maximum ball loading capacity of AG mill is calculated at 3% of effective mill volume, while the SAG mill with ball loading capacity at 15% of mill volume. ... CITIC HIC is responsible for setting the national standards of semiautogenous mills (SAG mills) and ball mils, supported by ...
WhatsApp: +86 18838072829Number, size and mass of each ball size depends on mill load and whether or not the media is being added as the initial charge. For the initial chargin of a mill, Coghill and DeVaney (1937) defined the ball size as a function of the top size of the feed,, dâ†"V = KâˆšF dB = ball size (cm) F = feed size (cm)
WhatsApp: +86 18838072829The SAG mill product is then crushed to 100% passing mm and is subjected to the Bond ball mill work index (SdBWI) grindability test to provide the total pinion energy at the specified grind size for mill design purposes, herein reffered to as micro ore hardness.
WhatsApp: +86 18838072829In this example, the OWi of the SAG mill was found to be 30% higher than the ball mill, thus suggesting that the SAG mill was less efficient than the ball mill. The apparent inefficiency of SAG mills when using Bond analysis is widely understood to be due to the difference in the slopes of the size distributions. In contrast, when the SSE75 was ...
WhatsApp: +86 18838072829Unfortunately I have a program for SAG mills and grinding circuits. Computational testing showed that: Capacity of SAG Mills can increase to 10000 t/h. The number of ball mills should be 24. The capacity of the SAG mill with precrushing by 2030% more than the SAG mill with the crashing critical size.
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