Experiment and analysis of the rock breaking characteristics of disc cutter ring with small edge angle in high abrasive grounds

Abstract

At present, the constant cross section (CCS) disc cutter with flat edge is widely used in TBM tunnelling project. But the problem of serious wear and low rock breaking efficiency appeared when the CCS disc cutter was driven into the high abrasive stratum. The disc cutter with small edge angle is designed in order to enhance the service life of the disc cutter in this paper. The simulation of the two kinds of cutter rings rock breaking were done based on the theoretical analysis used the theoretical model of CSM. It is found that the small edge angle cutter ring has good penetration and its performance is better than that of the flat edge cutter ring in high abrasive strata. The small edge angle cutter ring structure suitable for soft rock formation. The flat edge cutter ring has better performance in hard rock formation condition and is superior to the small edge angle cutter ring structure. The simulation results are consistent with the theoretical analysis. In the end, two different disc cutters having small edge angle and flat edge cutter ring, respectively, are used in the field cutting experiments performed by the authors of this study. The experiment results indicate that the small edge angle cutter ring wear faster than the flat edge cutter ring in the early stage of tunnelling, but it has higher driving efficiency, at the same time, prone to the phenomenon of edge collapse. Along with the advancing distance was lengthened, the excavating performance of small edge angle cutter ring is better after the edge angle wear flattened, and the service life than that of flat edge cutter ring slightly longer. The research results can provide a theoretical basis for the geological adaptability design of disc cutter in high abrasive grounds.