Research Of Cobalt Crust Spiral Mining Head Cutting Pick Fragmentation Characteristic And Arrangement Optimization

With the rapid development of economy and society, the demand for resources is increasingly enormous. As the gradual exhaustion of land mineral resources and deepening of human exploration of the marine resources, cobalt crusts becomes a remarkable strategic resource, because of its economic value. The deep-sea cobalt crust mining technology and equipment has become one of the most interesting research fields. The first step of cobalt crust mining is to break the cobalt crust resources from the submarine bedrock.The cutting pick on the mining head is the key component for the breaking, and its main function is to break and strip the cobalt crust. Reasonable cutting pick arrangement is the precondition for ensuring the efficient and stable operation of the overall system, which is also the key to extend the service life of cutting pick. On the basis of widely referring to the related material at home and abroad, the pick cutting mechanism, cutting pick structure parameters and its arrangement, and cutting head optimization are analyzed and discussed in this thesis. The researches are summarized as follows:1) After the appropriate simplification of the cutting pick shape, cutting mode and cutting parameters, several kinds of two-dimensional numerical model was established. One is a single cutting pick cutting cobalt crsut, including inclined and horizontal joints, and the other is two cutting picks cutting the horizontal joints with the sequential and simultaneous mode. Then the crack evolution of different joints parameters, cutting space and cutting sequence were obtained. According to the rule of crack propagation and the formation of fragmentation, six different kinds of crushing mode were classified. A further study of the cobalt crust characteristics was taken from the aspects of crushing efficiency, crack growth and crushing fragmentation.2) In the finite element environment of mining head cutting model, the cutting pick crushing cobalt crust model was established. The dynamic simulation of the cutting process of different cutting pick structure parameters and different kinds of arrangement was studied. Through the comparing of the performance evaluation of different parameters of ming head torque load fluctuations and energy consumption, the influence of various parameters on the ming head cutting pick performance was obtained. Then with the combination of experimental verification, a theoretical guidance for cutting pick structure design and arrangement was obtained.3) Using of genetic optimization design theory, the energy consumption and mining head load fluctuation were set as the optimization goals, then under the condition of meeting specific constraints, the mining head cutting pick arrangement parameters were optimized. Finally, the design parameters with ideal comprehensive performance were obtained. It provides a basis for the cobalt crust mining head design.