Design Research on Flange Join Bolt of Ball Mill

AUTHOR: admin DATE: 02 Apr 2012 04:08:39

Because the joint bolts of the ball grinder are uniformly distributed on the flange plant of the barrel, the load that it needs to sustain during the normal working process of the grinding mill will change regularly. Under this repeated alternate load effect, the bolt is very easy to rapture which may lead to connection failure of the barrel and the end cap. For this reason, it is very necessary and extremely important to check and examine the fatigue intension of the joint flange bolt of the grinding machine.

This fatigue question was first brought up by a German engineer W.A.J.Albert in 1829 according to an experience of the repeated load of a iron chain made by himself. Druing 1852 and 1869, another German engineer wohlerA did a systematic research on the fatigue damage and he was universally acknowledged as the founding father of fatigue question. From then on, this question was officially brought in the research field of science and the theories of this research are becoming richer and richer along with the constant exploration of the researchers and the research methods are even more various. The analytic methods that are widely used in the engineering projects are nominal stress, local stress political reform and damage tolerance.

So far many scholars have did a lot of research on the design of the flange join bolt of the ball mill barrel and it is mainly concentrated on the reliability design of the common join bolt. For example, Li Yenong did pragmatic research on the join bolt of the ball mill barrel and the end cap in his paper, and according to the specific parameters, he calculated the load operating on the blot and did stress distribution analysis and test and verification of the fatigue reliability. In addition, Chen Conggui introduced fuzzy reliability design methods into the design of join bolt of the ball mill, which takes into consideration the bolt strength and the uncertainty of the working load and introduced subjective experience into the design process.

Compared with the common connection bolt, the research on the ream hole bolt of the flange joint of the barrel of the grinding mill is scarce. Men Qingyi and Huang Guiqin carried on research on the conditions that the flange connection blot often raptures, through analyzing the force bearing condition of the bolt, they conduted stress analysis and checked and examined the strength and in the end, they figured out the reasonable using number of the ream hole bolt of the flange joint of the barrel of the grinding mill in order to make sure that the grinding equipment will work normally and reduce the maintenance time and cost.

However, the above analysis of the calculation of the working load only considers the static condition of the grinding equipment. If the equipment is working normally, the center of gravity of the material and the crushing media will shift which may produce some twist effect on the rotating machine. At the same time, the centrifugal force produced by the material and the crushing media will have a certain influence on the working load of the bolt. For this reason, the bolt load calculated on the static condition has pretty big deviation with the actual value and the fatigue strength examination is also not very exact. For further solutions, please contact Hongxing Machinery for answers since we are professional mining machines such as rotary kiln manufacturer.