Study Of CAE Technology On The Rotator Of Large-scale Semi-autogenous Grinding

The operation of ore crushing and grinding played an important role in the raw material industry. With the development of the economy and technology, the demand for metals and raw minerals is becoming stronger and stronger. New and large plants are built, old ones are expanded. This leads to the development of large-scale mill. To make sure the reliability of large-scale mill, researchers are now using an advanced computer-aided technology, which makes the calculation fast and accurate.SAG is the grinding mill that used for primary grinding of run-of-mine ore or primary crushed ore. The grinding medium is the ore itself, and it can enlarge grinding capability by adding balls. The use of SAG for grinding started in the 1950s and came to a climax in the 1970s. Entering 21st century, a large number of mines began to build and adopted semi-autogenous grinding technology. SAG is not only used for iron ore and copper ore grinding, but also widely used in other non-ferrous metal mines. The adoption of SAG can reduce the number of crushing, grinding and transport equipment , which makes the circuit simple , investment low , steel consumption low, while strengthening the throughput and bringing significant economic benefits.SAG is the mill with heavy-load, low-speed, long working cycles. The most important part is shell. The strength and stiffness of the shell can directly affect the mill operation and life-span. The tumbling shell rotates with complex loads including gravity, centrifugal force, impact, gear torque etc. The traditional ways simplify the shell to beam support, which can not accurately and fully reflect the stress and deformation.SAG is characterized with load when starting-up. This will undoubtedly increase the start torque and make the cost high. In practical application, it is usually difficult for SAG to start-up. As to this phenomenon, through theory dynamic analysis, this paper makes some mathematic simulation using the strong calculation software MATLAB. It really assists to choose the motor type and provides guarantee for the normal operation of the mill.With the reference of relevant documents, this paper takes the largest SAG in China as an example whose diameter is 9.75m and length is 4.26m. In this paper, the SAG structure is first introduced, the work theory and work states are also summarized, the lifter is taken as a transition to study the ore dynamic characteristics, calculations from both theory and practice are made; MATLAB language is used to simulate the dynamic process when starting-up. Through the research on three typical work conditions of SAG detailedly, new loading method was determined and adopted. ANSYS finite element analysis software was used to define the rotator stress, displacement distribution, and the first 5th natural frequency and mode shapes were picked up. In the paper the pre-feasibility estimates of large-scale SAG were made. The methods and results provide valuable references for testing of the products and are of great significance to the production.