Study On The Rotator Strength Finite Element Analysis For The Overflow Type Ball Mill

As the rapid and stable development of economy in China, a mass of metal raw material is needed in industry production and infrastructure. Crushing and grinding operation has been considerable development to meet this need. As the most common and universal equipment in beneficiation and metallurgy, the ball mill is more and more stringent in safety and reliability. The ball mill, whose crushing medium is the steel ball or cast iron ball, is mainly consist of cylinder part, feeding part, discharging part, bearings part, transmission part and lubrication part, etc. According to statistics, the main failure of ball mill occurs in solid of revolution in the actual production process, namely the part of the cylinder and end caps. The main reasons are the cracking of the end cap and the sudden fracture of attachment bolts of cylinder flange in ball mill. Therefore, the stress calculation of ball mill shell and cover, checking the cylinder flange bolts has extremely important significance to improve the fatigue strength of the reliability of ball mill and ensure security and stability in milling process.In order to study and solve these problems and ensure the ball mill can operate steady in normal conditions, this paper takes the MQY2747 ball mill as research object, makes the finite element analysis of strength of revolution, and checks the bolt's fatigue strength combining with fatigue design principles. Specifically includes the following aspects:1. Analysis the state of motion and force of crushing media in the cylinder body. Calculate the trajectory equation of the media while threw down by analysing structure and operating principle of ball mill, and calculate the encountered force of resolution while normal operating condition using mechanics principle, which make preparation for the subsequent finite element analysis of strength;2. Analysis and calculation of the power of the ball mill. Analysis the grinding process during which the electrical energy turned into mechanical and finally into the deformation energy of the ore. Analyze the theory and experience formula of available power of the ball mill, and then calculate the requested motor output power of 3. Research the solid revolution of MQY2747 ball mill, analyze the strength of the solid revolution using finite element method and conduct the modal analysis. Model the solid revolution of MYQ2747 ball mill according to the geometric parameter using ANSYS, calculate the stress distribution and deformation regular under 3 typical operating condition. Besides, modal analysis has been conduct, the first eight modal and mode of vibration are extracted. Results show that the natural frequency is far higher than the frequency of operation, which ensure to avoid the calibration.4. Through the research of the fatigue theory, check the fatigue of the ball mill flange bolt combine with the actual load situation. Calculate the equivalent stress of ordinary bolts and articulation hole bolts in flange respectively to ensure them not to fracture while working.This paper studied overflow ball structural strength of gyrorotor and fatigue strength of bolts, provided technical support to structural design of ball mill gyrorotor, ensured the safe production in the ball mill under the premise of minimizing the probability of failure, brought the huge economic benefits to the enterprise.