Comparative study on the rock breaking performance of constant cross section disc cutter and inserted tooth disc cutter for cutting granite

To compare the rock breaking characteristics of constant cross section (CCS) disc cutter and inserted tooth disc cutter, a multi-function cutting tool cutting performance test bench is used to carry out linear granite cutting tests of CCS disc cutter and inserted tooth disc cutter. Acoustic emission (AE) monitoring is carried out on the test process of the two cutting conditions, and the changing rules of rock fragmentation state, rock breaking load, rock breaking specific energy consumption and AE characteristic parameters are analyzed. The study results indicate that, under the same penetration conditions, the specific energy consumption of rock breaking is lower for CCS disc cutter than for inserted tooth disc cutter. The diagrams of AE localization distribution in different directions can reveal the state of rock surface breaking. A comparison shows that the state of rock surface breaking is better after cutting with the CCS disc cutter. The vertical load curve and AE energy curve of the cutter exhibit a dynamic correspondence, which varies continuously during CCS disc cutter cutting and in leaps and bounds during inserted tooth disc cutter cutting. Analysis of the RA and AF parameters of both breaking processes reveals that tensile cracks dominate, with a larger proportion of tensile cracks occurring during CCS disc cutter breaking. In summary, AE is used to distinguish between the rock breaking performance of CCS disc cutter and inserted tooth disc cutter. The results show that CCS disc cutter has a higher rock breaking efficiency in the process of breaking rocks, making it more suitable for cutting granite strata. The study results can serve as a basis for selecting cutter types for drilling granite formations.