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

삽입재 크기에 따른 코니컬 커터의 현장 내구성 평가 연구

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.

본 연구는 로터리드럼커터에 적용된 두 종류의 코니컬 픽커터에 대한 현장시험을 통해 시험 전과 후의 육안조사와 중량감소 및 마모부피를 측정하여 코니컬 픽커터의 내구성을 비교 분석하였다. 육안조사를 통해 슬림 타입 코니컬 픽커터에서만 총 9개의 삽입재 손실이 나타남을 확인하였고 삽입재 보호를 위해 두부의 두께가 중요함을 알 수 있었다. 시험 전과 후의 픽커터의 중량손실과 마모부피는 헤비타입이 슬림타입에 비해 반이하로 작게 나타나 경암반에서 헤비타입이 더 유용함을 확인할 수 있었다. 픽커터의 마모손실을 판단할 때, 중량측정과 마모부피 측정결과의 상호 비교는 재료의 단위중량과 굴착에 의한 스폴링에 의해 차이가 나타날 수 있으므로 주의해야 할 것으로 판단된다.

Fig. 1. Rock condtions in the field

Fig. 2. Conical picks

Fig. 3. Before and after the field tests

Fig. 4. Conical picks after test

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

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

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

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

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

Table 1. Hardness of conical picks

Table 2. Abrasion volume of heavy type conical picks

Table 3. Abrasion volume of slim type conical picks