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The objectives were to study on operating parameters influence of the covering soil performance and covering soil quality with the device, and analyzing the process and regulation of covering soil on plastic-film, setting up the key parameters equation of process of elevating and covering soil on plastic-film, and determining the test factors and its scope. Quadratic rotation orthogonal combination experiment was carried out. Parameters such as soil elevating scraper belt device speed, operation machine speed, level of two-way spiral filling device speed were selected as independent variables, which would influence qualified rate of soil cover. The mathematical model was established, and then the effects of various parameters and their interactions were analyzed as well. The test results showed that effects order of three parameters on qualified rate of soil cover were as follows: level of two-way spiral filling device speed, soil elevating scraper belt device speed and operation machine speed. The optimal working parameters of device were level of two-way spiral filling device speed of 432r/min, soil elevating scraper belt device speed of 1.56m/s and operation machine speed of 0.50m/s. Confirmatory tests showed that the average value of qualified rate of soil cover was 99.6%, which was promoted significantly compared with that before optimization. Discrete element method was applied to simulate the device with elevating and covering soil on plastic-film dynamic operation process under the condition of optimal parameters of elevating, conveying and covering soil. The simulation result was consistent with the field test conditions, which showed that the device optimization operation parameters calculation was accurate and reliable.