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Linear cutting machine test for assessment of the cutting performance of a pick cutter in sedimentary rocks

퇴적층 암석의 픽 커터 절삭성능 평가를 위한 선형절삭시험

  • Jeong, Hoyoung (Dept. of Energy Systems Engineering, Seoul National University) ;
  • Jeon, Seokwon (Dept. of Energy Systems Engineering, Seoul National University)
  • 정호영 (서울대학교 에너지시스템공학부) ;
  • 전석원 (서울대학교 에너지시스템공학부)
  • Received : 2017.12.07
  • Accepted : 2018.01.10
  • Published : 2018.01.31

Abstract

We carried out a series of linear cutting machine tests to assess the cutting performance of a pick cutter in sedimentary rock. The specimens were Linyi sandstone from China and Concrete (rock-like material, conglomerate). Using the small scaled LCM system, we estimated the cutter force and specific energy under different cutting conditions. The cutter forces (cutting and normal) increased with penetration depth and cutter spacing in two rock types, and it was affected by the strength of specimens. On the other hand, the ratio of the peak cutter force to the mean cutter force was influenced by cutting characteristic and composition of rock rather than rock strength. The cutting coefficient was affected by the friction characteristic between rock and pick cutter rather than the cutting conditions. Therefore, the optimal cutting angle can be determined by considering of cutting coefficient and resultant force of pick cutter. The optimum cutting condition was determined from the relationship between the specific energy and cutting condition. For two specimens, the optimum s/p ratio was found to be two to four, and the specific energy decreased with the penetration depth. The result from this study can be used as background database to understand the cutting mechanism of a pick cutter, also it can be used to design for the mechanical excavator.

Acknowledgement

Supported by : 건설교통과학기술진흥원

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