Ma, Q. and Deng, F. and Lei, L. and Ma, J. and Liu, K. and Liu, L. (2019) 莲仁钻削去心过程力学特性及减损工艺参数优化. Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering, 35 (9). pp. 291-300.
Full text not available from this repository.Abstract
Removal of lotus core is one of the important processes in lotus kernel processing. Mechanical removal of lotus core is to use rotating drill to break up and break out lotus core along the axial direction of lotus kernel. The so-called crumbling of lotus kernel refers to the phenomenon of spalling and crushing of lotus kernel. In order to minimize the processing losses and reduce the processing costs of lotus kernel in the process of drilling lotus core, and find out the influence law of the related process parameters on the crumbling of lotus kernel during the process of drilling core, in this paper, the mechanical analysis, simulation, test and process parameter optimization on the process of drilling lotus core were carried out. 1) The stress state of lotus kernel during core removal was analyzed, including the overall stress analysis of lotus kernel and the drilling force analysis. And the mechanical model of lotus kernel in drilling was established. The main factors affecting the crumbling of lotus kernel during core removal were analyzed, such as the clamping force of press roller, the drill diameter, the drill speed, the feeding rate of drill and the water content of lotus kernel. 2) Based on the related physical parameters of lotus kernel in other literatures, the DEFORM 3D finite element method was used to simulate the core removal process. Through the corresponding post-processing of the simulation results, the variation curve of axial drilling force with time and strain contours of lotus kernel under different process parameters were obtained. By analyzing curves and strain contours,the influence law of each process parameter about the crumbling of lotus kernel was obtained. And we found out the most vulnerable place to peel off in the process of core removal. 3) The drilling force was tested by Kistler dynamometer in the process of core removal. The actual axial force-time curve in the drilling process was obtained, as well as the influence curve of drill speed, feeding speed of drill and drill diameter on the axial drilling force was obtained by test. By comparison, it was found that the test results were basically consistent with the simulation results. 4) Based on the designed lotus kernel coring test bench, the influence of water content, clamping force of press roller, drill speed, feeding speed of drill, drill diameter and other process parameters on the crumbling rate of lotus kernel was tested by single factor test method. And on the basic of the single factor test results, the optimum technological parameters were obtained by orthogonal optimization test. The optimum technological parameters were as follows: The water content was 7.78%,the drill diameter was 2.2 mm, the clamping force of the press roller was 38 N, the feeding speed of drill was 20 mm/s, and the drill speed was 3 000 r/min. The result of this study can provide a reference for the design of equipment of lotus core removal by drilling.