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Durability evaluation depending on the insert size of conical Picks by the field test

삽입재 크기에 따른 코니컬 커터의 현장 내구성 평가 연구

  • Choi, Soon-Wook (Department of Infrastructure Safety Research, Korea Institute of Civil Engineering and Building Technology)
  • 최순욱 (한국건설기술연구원 인프라안전연구본부)
  • Received : 2018.10.15
  • Accepted : 2018.11.16
  • Published : 2019.01.31

Abstract

In this study, the durability of conical pick cutter was compared and analyzed by pre- and post-test visual inspection, measurement of weight loss and wear volume through field test on two types of conical pick cutters applied to rotary drum cutter. In the visual inspection, it was found that only 9 inserts were lost in the slim type conical pick cutter. This result show that the thickness of the head cover surrounding a insert was important to maintain the insert during excavation. The weight loss and wear volume of the heavy type conical pick cutter were less than half that of the slim type. From these results, it can be confirmed that heavy type is more useful than slim type in hard rock. It should be noted that, when determining the wear loss of the conical pick cutter, the mutual comparison of the weight measurement and the wear volume measurement results may be different due to the unit weight of the material and the spalling caused by excavation.

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Fig. 1. Rock condtions in the field

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Fig. 2. Conical picks

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Fig. 3. Before and after the field tests

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Fig. 4. Conical picks after test

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Fig. 5. Weight loss of heavy type conical picks (working time 4 hour)

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Fig. 6. Weight loss per hour of heavy type conical picks

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Fig. 7. Weight loss of slim type conical picks (working time 1 hour)

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Fig. 8. 3D Image example of heavy type conical pick (tenth pick on the left drum)

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Fig. 9. 3D Image example of slim type conical pick (34th pick on the left drum)

Table 1. Hardness of conical picks

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Table 2. Abrasion volume of heavy type conical picks

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Table 3. Abrasion volume of slim type conical picks

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Acknowledgement

Grant : 대심도 복층터널 설계 및 시공 기술개발

Supported by : 국토교통과학기술진흥원

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