A Simulation Study on the Cutter Loads on the End Face of DTH Bits

In order to make the DTH bit tooth arrangement more reasonable and to provide a theoretical basis for the improvement of bit structure, so as to improve the rock breaking efficiency of the DTH bit and to prolong its service life, it is necessary to understand the load distribution on the end face of DTH bit. Therefore, a three-dimensional model for DTH bits has been established, with three kinds of end faces, including plane, convex face and concave face, which taken the H-J-C of explicit dynamic analysis software ANSYS/LS-DYNA as the material model, and used the equivalent yield strength, pressure and accumulated damage of H-J-C to simulate the rock breaking process of DTH bits.The load status of cutting teeth on different tooth rings has been analyzed, and they decomposed the loads into three directions:i.e. axial, radial and tangential. At the same time, the mechanical analysis for cutting teeth of the DTH bit with three kinds of end faces were conducted by controlling variables. Research results showed that DTH bits with concave surfaces had maximum axial loads and minimum radial loads; the main differences of loads on cutting teeth of DTH bits were reflected predominantly by side teeth and neighboring teeth, it has little relation with the cutting teeth on the other rings. With maximum loads, side teeth on DTH bits are susceptible to damage. Simulation results may provide reliable guidance for selecting and arranging the cutting teeth, and for designing the structure of DTH bits.