Improving the reliability of the hammer grain crusher by optimal design of the paddle wheel

Abstract

Now in agricultural production there are significant changes in the fleet of equipment due to the renewal of the material and technical base with improved parameters for quality, reliability, durability and operability in difficult operating conditions. However, the manufacturing industry still has a large number of outdated equipment that requires modernization through optimal design of machine components and parts. So, in the process of feed preparation, closed-type grain crushers are widely used, working on the principle of suction of the source material and injection of the finished product. This type of crushers undergoes significant abrasive wear of working bodies (drums, hammers, sieves, etc.) due to their suboptimal geometric shape of transition surfaces, where local stresses accumulate, as well as in areas of contact of parts with particles of gas-dispersed material. The blades of the drum wheel are subjected to particularly severe wear, for the restoration of which significant material costs are required during major repairs. The paper presents theoretical studies of contact stresses during wear of working surfaces, a criterion and condition for the optimal position of the blade are proposed. The optimal position of the blade has been determined - it must be positioned at an angle of 10 ° to the axis of the drum wheel. The results of field tests of the upgraded crusher allow us to conclude that the reliability indicators (durability of the blade drum and reliability of the crusher) increase by more than 3 times.