Research On Nonlinar Coupling Characteristcs And Condition Assessment Of Vertical Steel Guide System

As the guide device of the hoist conveyance, the steel guide system can decrease the horizontal vibration in the hoisting process and make the hoist conveyance move smooth in the vertical direction. The steady of the conveyance as well as the safety were directly influenced by the working condition of the steel guide. The dynamic test method was used to identify the true working condition through the vibration parameters of conveyance, which has great significance to the maintenance of the steel guide facilities. The dissertation was based on the research of coupled dynamics model of the steel guide- hoist conveyance-steel wire rope system, the construction of dynamic test system, the analysis and fault detection methods of the dynamic test signal were developed and the condition assessment of steel guide system was established.On the research of the dynamics mode of the steel guide system, with the help of simulation and experiment verification,the vertical vibration mode of rope-conveyance system in multi-rope friction hoisting situation was established to identify the frequency composition,as well as its origin and influence. Then 6-freedom coupling dynamic model of the hoist conveyance was established, taking the elasticity of the steel guide, the nonlinear interval of the guide shoe spring and the elasticity of the steel wire rope into account, which makes the model closer to the actual steel guide system in dynamic situation; also different steel guide faults and its displacement excitation function were classified,then the conveyance's vibration acceleration responses were simulated under different steel guide faults excitation with different working conditions. At last, the rationality of the model was tested through the field experiment results analysis.The steel guide dynamic test system was established based on virtual instrument technology. The specific scheme of the dynamic test was confirmed, including the selection of the physical parameters, the mounting position of the sensor, the selection of the test working condition and the synchronization test of the location displacement. Second, the measuring system based on the virtual instrument technology was established with the design of the hardware and software. The sensors with different bandwidth were combined to meet the acceleration dynamic test requirements under normal working condition.Various time-frequency signal process method and intelligent algorithm were utilized to the research on the data process and fault diagnosis of dynamic test results. The characteristic parameters of the vibration signal are extracted by Laplace correlation filtering method, together with the time domain peak value as the condition attribute, and then were reduced by the rough sets theory, with the excellent approximation and classification ability of the RBF neural network, the impulse fault degree of the steel guide was assessed. Through the multiresolution decomposition method based on the harmonic wavelet packet, the energy distribution of the testing signal caused by the spacing change between the steel guides was analyzed by the attribute-weighted fuzzy clustering algorithm.The steel guide condition assessment system based on dynamic test was established by the fuzzy comprehensive evaluation method. First, the author established the steel guide condition evaluation parameters system and the standard of steel guide dynamic test method were put forward by conveyance vibration response analysis. The corresponding assessment system was set up by the static and dynamic testing results as well as field specialist evaluation, the validity of the steel guide condition assessment mode then was tested by field experiment examples.