Research On Main Shaft's Skip Weight-fixed Loading System Of Coal Mine

For the problem of partly old main shaft's skip hoist systems cannot achieve weight-fixed loading, this paper adopted hydraulic-weighing method and programmable logic controller, designed the main shaft's skip weight-fixed loading system. The paper researched the dynamic characteristic of hydraulic system, analyzed the impact of weighing accuracy and dynamic characteristics of the hydraulic system on the pipeline parameters, expounded the selection on the PLC and analog input module, and the distribution on I/O points, established the diagram of the PLC and controlled flow chart. And last, the main shaft's skip weight-fixed loading system is studied experimentally. The results showed the main shaft's skip weight-fixed loading system can increase the degree of automation loading and safety production. The main contents of the research are as follows:(1) The design of weight-fixed loading system focus on Wangshiwa coal mine, in accordance with the site and actual conditions, the paper obtained the principle chart of weight-fixed loading hydraulic system, drew the diagram of the PLC, control flow chart and MCGS-based monitoring interface. The PLC-based control system used the method of "one-up" redundancy design, with high reliability, operated easily and other features, the MCGS-based monitor computer system has the functions of working condition monitoring, fault diagnosis, statements printing and so on.(2) For the weight-fixed loading hydraulic system, the pipeline not only as a bridge of connecting transmission and controlled devices, but also as oil capacity cavity, it has a major impact on the weighing accuracy, therefore, the study of dynamic characteristics on pipeline is essential. The paper established lumped parameter model and the simulation model, analyzed the characteristic of flow rate and pressure on the pipeline's section number, which obtained the conclusion that every one-meter long pipeline divided into two sections can be achieved fine effect on the accuracy of the simulation.(3) The paper focus on the relationship between the pipeline and weight-fixed loading hydraulic system, for access to the dynamic characteristics of the hydraulic system, the paper established the mathematic and simulation model, researched the dynamic characteristics of hydraulic system with long pipeline. Through analyzing on the performance criteria of system response, the results were compared with the pipeline material, length and other diameters of the hydraulic system, provided a theoretical basis for the future design of similar system.(4) Based on the weight-fixed loading of Wangshiwa coal mine, the laboratory and field experiments were carried out, including the start-up and operation of hydraulic system, the impact of loading process simulation of laboratory and production site loading, as well as produce the measured data from the pilot's perspective. The experimental results validated the above theoretical analysis, proved the feasibility of monitoring and control system, and the accuracy of theory and simulation analysis.