Design and experiments of a double drum surface residual film recycling machine after harvest

Residual film recycling machines cannot fully meet the requirements of large-scale production of residual film. Serious film entanglement and winding can often occur in the bearing part. The cotton straw cannot be completely broken, thus leading to the low film content of the recovered film. It is very necessary to improve the pick-up rate with less straw content from the recycling mixture in the residual film recycling machine. In this study, the double-roller residual-film recycling machine was designed suitable for surface residual film recycling after the autumn harvest. The pneumatic and mechanical collaborative film was unloaded to realize the operation using mechanical film picking. The key components were determined to better design the film recycling machine. The kinetic analysis of film picking and unloading was carried out to match the range of working speed, in order to overcome the interference among the machinery. The key structural parameters were determined for the film-picking and unloading device. The center motion trajectory of the roller and the forward and reverse cam orbits were optimized to determine the cam structure parameters. Mathematical and graphical analysis was used to obtain the conditions of no missing in the film-picking device. The film unload device was simplified in the software to divide the grid. The data was then imported into the flow analysis software. The flow field was simulated inside the film unloading device. A systematic investigation was implemented to explore the influence of the flow field on the transport of the residual film. The results show that the "O" shape rotation formed by the airflow was a benefit to the separation of residual film and impurities. Single-factor test was carried out with the rotating speed of the film picking and unloading roller as the test factors, according to the forward speed of the machine. The operating parameters of the machine were obtained, including the optimal operating range of the forward speed, the rotating speeds of the film picking and removing roller. The response surface test was then designed to verify the effectiveness of the machine, with the forward speed of the machine, the rotating speed of the film picking and unloading roller as the test factors, and the pick-up rate of the residual film and the straw content rate of the recovered mixture as the test indexes. The analysis of variance was performed after the test. The regression equations were obtained for the pick-up rate and straw content rate. The optimal working parameters were obtained to optimize the factors. The test results show that the operation performance was better, when the forward speed of the machine was 6.7 km/h, the rotating speed of the film-picking roller was 57 r/min, and the rotating speed of the film-removing roller was 570 r/min. A field verification test was carried out under the optimal combination of parameters, the results showed that the mean value of residual film pick-up rate was 86.1% and the straw content rate of the recycling mixture was 39.2%, compared with the existing film recycling machine, the residual film pick up rate isincrease 1.07 percentage pionts, and all indicators meet the requirements of the surface residual film recycling machine afterharvest.