| Mine hoist is widely used in mining industries of coal, nonferrous metal, and ferrous metal and so on. As the key machinery in mining system, mine hoist which is called"throat equipment"bears lifting minerals, people, materials and equipments. The technical performance of hoist which is paid great attention to has direct influence on mine production efficiency and miner life safety. As an important part of hoist, the forced state, real load spectrum and some design coefficients of main shaft device could not be determined at present and some structures could not be evaluated completely and correctly, so modern design method is needed urgently to reflect global stress and strain distribution of hoist. Traditional calculation method of the strength and stiffness of main shaft device is analytical method. This method which ensures structural strength and stiffness by increasing safety coefficient can only calculate roughly and just obtain local stress, displacement, strength and stiffness. However, global structural stress and strain distribution can be calculated quickly, correctly and intuitively by finite element software. Meanwhile, detail optimization can be realized through the use of finite element software, which is incomparable to traditional calculation method.The main shaft device of 2JK one rope winding mine hoist is studied in this thesis. The modeling, solution and post-processing of the main shaft device are realized by Pro/ENGINEER, HyperMesh and ANSYS software and so on. The parts are meshed by shell elements and solid elements respectively, the node coupling method is used to simulate the connections between supporting wheels and shaft, and MPC184 elements are used to simulate the bolt connections between supporting wheels and drums. Meanwhile, the optimization of manhole structure which has stress concentration phenomena is studied.The results show that: (1) Simulation of bolt connections using MPC184 elements can solve both the problems: one is the incoordination between shell elements and solid elements, another is simulation of the load transfer in parts. The model established is reasonable. (2) The strength and stiffness of the main shaft device are verified to meet operating requirements, and the stress distribution of assembly structure is achieved, which provide evidence for the studies of further analysis and improvement design. (3) The manhole structure is optimized using OptiStruct software for the first time, and satisfactory results are achieved, which improve the stress distribution of manhole border and reduce the possibility of fatigue failure. Finally, some conclusions are achieved as follows:â‘ The maximum equivalent stress of manhole border decreases and the stress distribution tends to be more uniform with the decrease of the distance between manhole and the center of drum;â‘¡The size parameters A and D2 have greater impact on manhole border stress and the law is: the maximum equivalent stress of manhole border decreases and the stress distribution tends to be more uniform with the decrease of A and D2;â‘¢The manhole border stress of original structure can be improved by circular manhole;â‘£The numbers and relative position of manholes have less impact on manhole border stress. Meanwhile, a new way to improve structure is provided. (4) Some useful conclusions are achieved by finite element simulation and optimization of the main shaft device, which provide a basis for the design of main shaft device and have great significance in engineering application. The results also prove that the use of finite element analysis software to calculate can greatly reduce design time, improve the efficiency of the design and have important engineering value to study lifting equipments by means of finite element analysis software.
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