What is SAG milling?
SAG mill. SAG is an acronym for semi-autogenous grinding. SAG mills are autogenous mills that also use grinding balls like a ball mill. A SAG mill is usually a primary or first stage grinder. SAG mills use a ball charge of 8 to 21%.
How does a sag mill work?
Working: SAG mill make use of steel balls included with some large and hard rocks for grinding. Repeated collisions between the steel balls and raw materials (ore), divides the material into finer and smaller pieces. This whole process takes place inside the large drum of SAG mill.
How much does a sag mill cost?
The SAG mill cost $12.2 million, whilst the SAG mill motor cost A$8.8 million for a total of A$21 million. Laboratory test work data, shown in Table 1, indicated hard and competent ores (monzonite, monzodiorites and volcanics), although not necessarily of such competency as to create concern.
What is a grinding circuit?
Grinding circuits are fed at a controlled rate from the stockpile or bins holding the crusher plant product. There may be a number of grinding circuits in parallel, each circuit taking a definite fraction of the feed. An example is the Highland Valley Cu/Mo plant with five parallel grinding lines (Chapter 12).
What is a rod mill?
Definition of rod mill 1 : a mill that produces rods of steel or other metal. 2 : a pulverizing machine that uses loose iron rods as the grinding media — compare ball mill.
What is grinding in mineral processing?
In minerals processing most of the minerals are very finely disseminated or associated with the waste (or the “gangue”) fraction of ore. Grinding (and/or milling, which is a form of grinding) is accomplished by abrasion and impact of the ore by the free motion of unconnected media such as rods, balls, or pebbles.
How can I make my SAG mill faster?
The energy storage capacity and processing speed can be increased by adding one of 3 tier of Capacitor into the upgrade slot. The energy consumed varies on the item processed. To increase the chance of getting a secondary output add a catalyst such as Flint or Dark Steel Ball.
Is milling the same as grinding?
While they both involve the physical removal of material from a workpiece, milling and grinding aren’t the same. The former machining process is characterized by the use of a milling machine, whereas the latter machining process is characterized by the use of a grinding wheel.
What is critical speed of ball mill?
A Ball Mill Critical Speed (actually ball, rod, AG or SAG) is the speed at which the centrifugal forces equal gravitational forces at the mill shell’s inside surface and no balls will fall from its position onto the shell. The imagery below helps explain what goes on inside a mill as speed varies.
What is open and closed circuit grinding?
The characteristic differences between open- and closed-circuit grinding systems were examined via the use of a continuous vibration ball mill and a blade type classifier. For the same median diameter of the product, the rate of powder production in the closed-circuit is about 5% higher than that of the open-circuit.
What is a ball mill used for?
A ball mill is a type of grinder used to grind and blend bulk material into QDs/nanosize using different sized balls. The working principle is simple; impact and attrition size reduction take place as the ball drops from near the top of a rotating hollow cylindrical shell.
What are the characteristics of a SAG mill?
The biggest characteristic of the sag mill is that the crushing ratio is large. The particle size of the materials to be ground is 300 ~ 400mm, sometimes even larger, and the minimum particle size of the materials to be discharged can reach 0.1 mm.
What is the difference between AG and SAG milling?
In practice, for a given ore and equal processing conditions, the AG milling has a finer grind than SAG mills. How does a sag mill work?
What is the difference between SAG and ball-mills?
Restated, the designed SAG mill size and operating conditions typically control circuit throughput, while the ball-mill circuit installed power controls the final grind size.
What is the power draw of SAG mill control loop?
The original SAG mill control loop, a mill motor power draw set point of 5200 Amperes controlling the coarse ore feeder speeds, was soon found to give excessive variation in the mill ore charge volume and somewhat less than optimal power draw.