Screen panel size is 28 by 54 inches. The oversize return tube turns with the trommel These things are not small. The diameter of the trommel for the 34-foot mill is 13.5 feet and the screen surface length is almost 13 feet. This gives us about 550 square feet of screen area, for roughly 30,000 tons a day or 1,300 tons an hour.

Ball mills: Ball mills are the stalwart unit of the majority of pilot grinding circuits. ALS has a range of rubber lined overflow ball mills including: 2.3kW, 4.4 kW high aspect (900 mm Dia x 400 mm EGL), 3 x units of 5.5 kW and 7.5 kW (900 mm Dia x 790 mm), 1 x 15 kW 900 mm Dia x 1800 mm EGL, 1 x 30 kW 1240 mm Dia x 1440 mm EGL).

Each time the grate enters the mill charge, the horizontal force of the load in the mill deflects the grate. This stretches the rubber and forces any large material …

SAG Mill internal volume model: As the slot grate model, this model was developed using scanning measurements inside the mill. For this particular purpose it wasn't used the …

AG and SAG mills are now the primary unit operation for the majority of large grinding circuits, and form the basis for a variety of circuit configurations. SAG circuits are common in the industry based on: High single-line capacities (leading to capital efficiency) The ability to mill a broad range of ore types in various …. Read more.

You need more tonnage and could actually use a larger/coarser transfer size from the SAG to Ball Mill. The ore is "hard" and "bulky". ... Finer feed (i.e. secondary crushed) justifies a 4″ ball but if the grate opening is 60 mm x 100 mm slots then a 4″ ball won't last very long. If the feed top-size is >100 mm, then typically a 5 ...

These are ideal for high throughputs and a coarse product to feed to a secondary ball mill for further size reduction. Medium aspect mills are common in Australia, with aspect ratios between 1.2 and 1.5. ... To obtain these rates the discharge grate slots are enlarged to all be pebble ports. ... as illustrated in Figure 3. SAG 1 SAG 2 ...

SAG Mill. Full case in PDF. ME Elecmetal's integral approach to mining is committed to add value into processes through fully-integrated ME FIT solutions. In this case, by testing new SAG mill liner designs in order to …

The amount of pebbles passing through the grate increases with the angle of the grate. It is imperative to ensure the efficient removal of both slurry and coarse pebbles (critical size) in order to ensure the efficient operation of AG/SAG mills. Elimination of the above mentioned material transport problems will allow the mill to respond truly ...

Similar to slurry flow-back, the pebbles flowing back into the mill increase with larger pebble port or grate slot size. As the pebbles flow down and slide across …

No pebble ports in the grates (SAG circuit). b) Semi autogenous grinding in which the pebble fraction of mill discharge (+½ in.) is taken out through pebble ports for separate crushing and ball milling. The minus ½ in. fraction of mill discharge is recycled to the SAG mill through a classifier.

Grate Slot Size Reduction. ME Elecmetal's integral approach to mining is committed to add value into processes through fully-integrated ME FIT solutions. In this case, by testing new SAG mill liner designs in order to …

A Discrete Elements Method (DEM) study of load movement within a SAG mill 12,192 × 7620 (40′ × 25′) in normal operating conditions is performed. ... since the exit flow is restricted to only those particles of a size smaller than the grate's slot, a size that has been defined previously. It was decided to use 71.4% of the ore particles ...

The size distribution of the SAG mill feeds and plots is linked to the strength of the rock; a slope with a discharges during the five surveys are shown in Figures 10 steeper gradient indicates a weaker rock. ... It is grate slot size could not solely control the mill product size fact that the grate open area variable is out of the control of ...

Keywords: grate, SAG-Mill, DEM-Simulation, flow-back, carry-over 1. Introduction Size reduction of ores has an important role in the process of obtaining various metals. For …

The load in such a mill typically contains 250,000–450,000 particles larger than 6 mm, allowing correct representation of more than 90% of the charge in Discrete Element Method (DEM) simulations. Most AG/SAG mills use discharge grate slots which are 15 mm or more in width. The mass in each size fraction usually decreases rapidly below grate size.

The Bradken Vortex® Discharge System: Provides superior discharge performance for SAG and AG mills. Is ideally suited to high throughput, high solids discharge mills. Increases ore throughputs. Increases pulp lifter wear life. Our one-piece Super Vortex® Grates cover the full depth of the charge to maximize grate open area and mill …

Download scientific diagram | Grate slot size variation from publication: Development of a dynamic Jb/Jc estimation model in a single stage SAG mill | The following article presents the...

Grate Slot Size Reduction ME Elecmetal's integral approach to mining is committed to add value into processes through fully-integrated ME FIT solutions. In this case, by testing new SAG mill liner designs in order to improve throughput, …

Grate design should incorporate an integral radial lifter. This lift on a grate can increase the grate life by up to 50 percent. The slot opening size is determined by the lump size to be retained in the mill. Grate plugging is minimized by …

The role of the grate is to allow the discharge of the material ground in the mill via the slots. With our range of alloys and design experience we can offer the longest possible lifetime with the optimal grinding efficiency. The design of the grates will depend on: Drilling pattern; Mill speed (rpm) Maximum grinding media diameter (mm)

Felipe González & Paola Merino. 266 Accesses. 6 Citations. Explore all metrics. Abstract. A Discrete Elements Method (DEM) study of load movement within a …

For large mills, using 125 to 140 mm (5 to 5-1/2 in.) feed ball size, conventional new lifter-liner dimensions are around 300 to 350 mm (12 to 14 in.) overall height above the shell, …

The SAG Mill has a "small" circulation load of oversize given be the 3/8″ trommel screen and the 1/2″ x 1 1/4″ discharge grates. The load of 4″ balls in this SAG is "good" but un-measured. SAG Ball …

The load in such a mill typically contains 250,000-450,000 particles larger than 6 mm, allowing correct representation of more than 90% of the charge in Discrete Element Method (DEM) simulations. Most AG/SAG mills use discharge grate slots which are 15 mm or more in width. The mass in each size fraction usually decreases rapidly below grate size.

The finding in this research is to reveal the condition in which a reliable DEM solution is achievable in the appli-cation of a SAG mill. The DEM result sheds insight to the design of the grates like the size and total opening area of the slots. It also provides structural optimization on a new type of grate used in a SAG mill.

Bradken Bullnose®discharge cones Manufactured from superior composite wear materials to extend wear life of the liners and reduce the overall weight by 40% over steel products.Bullnose® discharge cone system reduces the relining times by 50% to maximise mill availability. Discharge grate slot analysis is carried out across all grate designs to …

Grate Discharge Ball Mills have shown 25% to 45% more tonnage ground and a substantial reduction in power consumed per ton of material compared size for size with overflow mills. To illustrate the characteristics of various type mills we have shown the types of discharge for rod mills and ball mills. There are essentially four types of rod …

All autogenous (AG) and semi-autogenous (SAG) mills use steel or rubber grates to hold back the grinding media, whilst allowing the product slurry to flow through and out of the mill. The total open area, size, shape and position of the holes varies considerably from installation to installation (Napier-Munn et al., 1996), as given in Table 1.

SAG mill grates must withstand difficult conditions in order to maintain the desired throughput. But traditional steel grates aren't up to the challenge. They are typically cast from a material between 250 and 300 Brinell hardness – i.e. fairly soft, to avoid breakage – but the result is that they are easily deformed, causing grate slots ...