991r/min 5.5×2.5m Ore Grinding Mill Sag Ball Mill For Mineral Processing

AG Mills&SAG Mills:φ2.4x1.2~φ13x4.0m,Effective volume 5.6~216m3;

The CITIC autogenous / semiautogenous mills are utilized to grind run-of-mine rock or primary crusher discharge.
The feed size to this mill is limited to the maximum size that can be practically conveyed and introduced into the mill.
The mill product is either finished size ready for processing or an immediate size ready for final grinding in a ball mill, pebble mill, or a VERTIMILLTM.
Wet grinding is accomplished in a slurry of 50 to 80 percent solids. AG/SAG mills can accomplish the same size reduction work as two or three stages of crushing and screening, a rod mill, and some or all of the work of a ball mill. Because of the range of mill sizes available, AG/SAG milling can often be accomplished
Grinding Circuit Design
AG/SAG milling can be accomplished with a variety of flowsheets. The optimum flowsheet should be established during the testing of the ore.
Common flowsheets include:

• AG-Single Stage
• AG in a closed circuit with a crusher
• AG with a crusher + ball mill
• SAG-Single Stage
• SAG with ball/VERTIMILLTM

CITIC AG Mills&SAG Mill Feature
♦ The cylindrical mill adopts the driving type edge-driving, center-driving, edge-driving with multi-point meshing, etc; driven by asynchronous motor +reducer +pinion and gear as well as synchronous motor +
air lclutch + pinion and gear.
♦ Generally supported by static-dynamic pressure bearing on both ends. Fuuly closed self-aligning 120º osculation rocker bearing is used. Also single or double slipper staic- dynamic bearings can be used. The bush is made by NC machine.
♦ The large open gear is designed using AGMA standard, Equipped with reliably sealed gear housing and grease ahtomatic spraying lubrication system.
The shell is key part of a mill. Carry out finite element analysis on it with computer to ensure the reliable operation;
♦ The shell is automatically welded, ultrasonic inspected, wholly annealed and machined by large special machine tools on one chucking; there special seal on static-dynamic connection parts , ch as feed and discharge hoper, trunnion, etc, to prevent oil and slurry leakage;
♦ The liner is of wear-resistance material mad by our company, wich has been specially heat-treated, with high hardness and long service life. Also other wear-resistance casting or rubber liner can be used;
♦ There are slow speed drive for medium and large mill;
♦The high and low pressure lubricating station is equipped for medium and large mill;
♦The control and protection system is controlled by PLC.
Description of Semi Autogenous Mill(SAG Mill):
This semi-autogenous mill, also called semi-autogenous grinding mill or SAG mill, is mainly used to grind ores and other particulate matter in different fields, like chemical industry, mining field, metallurgy industry, building material sector, and so on.
It is an autogenous mill in nature, but it employs grinding balls to assist in its grinding just like in a ball mill. And it is mainly used in the first stage of grinding. When compared with a ball mill, it is characterized by its larger diameter and shorter length. The inside of it is lined with lifting plates to lift the materials inside up and around the inside of the mill, where it then falls off the plates into the rest of the ores. And it is widely used to process gold, copper, lead, zinc, alumina, nickel, platinum, etc.

AG (Autogenous) / SAG (Semi-autogenous) Grinding Mills
Autogenous (AG) and Semi-Autogenous (SAG) grinding mills have seen increased application in large mineral processing operations in recent years. They are rotating/tumbling mills in which comminution (size reduction) takes place without grinding aids. Consisting of a large diameter cylinder relative to their length (typically 2 or 2.5 to 1) these mills use large lumps of ore as the grinding media. Autogenous mills use ore exclusively as their grinding media but if hardness and abrasiveness of the ore does not lend itself well to full AG milling then a small charge of steel balls (6 to 15%) is added to assist in size reduction. This is known as a Semi-Autogenous (SAG) mill. AG/SAG mills bring about size reduction by a combination of impact, attrition and abrasion forces. Ore is swept up one side of the mill and at a certain point it falls back to impact the toe of the charge (bottom of mill). Ore particles in the body of the charge slide when moving to different heights and are subjected to attrition and abrasion forces. The inside liner of AG/SAG mills consists of steel or rubber liners and are fitted with lifter bars.
AG/SAG mills can accomplish the same size reduction work that normally takes multiple stages of crushing, screening and grinding methods which accounts for its popularity. Often the product can be finished size or ready for final grinding in a ball mill or pebble mill. They can grind run-of-mine rock or primary crusher products with their feed size limited to what can practically be conveyed. In addition they can be less costly to operate with the reduction or elimation of expensive balls or rods.