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Development of the Accelerated Life Test Method & Life Test Equipment for the Counterweight of the Construction Machinery

건설기계용 카운터웨이트 시험장비 및 가속수명시험법 개발

  • Lee, Gi-Chun (Korea Institute of Machinery & Materials, Reliability Assessment Center) ;
  • Lee, Young-Bum (Korea Institute of Machinery & Materials, Reliability Assessment Center) ;
  • Choi, Byung-Oh (Korea Institute of Machinery & Materials, Reliability Assessment Center) ;
  • Kang, Bo-Sik (Korea Institute of Machinery & Materials, Reliability Assessment Center) ;
  • Kim, Do-Sik (Korea Institute of Machinery & Materials, Reliability Assessment Center) ;
  • Choi, Jong-Sik (Korea Institute of Machinery & Materials, Reliability Assessment Center) ;
  • Kim, Jae-Hoon (BK21 Mechatronics Groups, Dept. of Mechanical Design Engineering, Chungnam Nat'l Univ.)
  • 이기천 (한국기계연구원 신뢰성평가센터) ;
  • 이용범 (한국기계연구원 신뢰성평가센터) ;
  • 최병오 (한국기계연구원 신뢰성평가센터) ;
  • 강보식 (한국기계연구원 신뢰성평가센터) ;
  • 김도식 (한국기계연구원 신뢰성평가센터) ;
  • 최종식 (한국기계연구원 신뢰성평가센터) ;
  • 김재훈 (충남대학교 기계설계공학과)
  • Received : 2014.09.04
  • Accepted : 2015.10.05
  • Published : 2015.12.01

Abstract

A large-sized exciter that vibrates a two-ton component is required to simulate the field operating conditions of a counterweight of an excavator. However, it is difficult for a small-medium sized company to obtain a large exciter for the life test of a counterweight which is an equivalent counterbalancing weight that balances a load. Therefore, in this study, we developed life test equipment for evaluating the reliability of construction machinery weighing about two tons. It simulates the field operating conditions using rotational vibrators consisting of electric motors. A failure analysis of the counterweight was also performed for the major components. Field data acquired from various sites were applied to the life test design of the counterweight. Finally, a zero-failure qualification test based on the accelerated life test was designed, and there was no failure during the test, which guarantees a life of $B_5$ 10,000 hours.

카운터웨이트를 수명시험 하기 위해서는 실제 현장과 유사하게 2 톤의 무게를 가진시켜 주는 대형 가진기가 필수적이다. 그렇지만 이러한 장비를 일반업체에서 보유하여 시험하기는 어려우므로, 이러한 애로점을 해소하기 위해 본 연구에서는 첫번째로 2 톤의 중량물일지라도 건설기계의 신뢰성을 평가하는 전기터들로 구성되는 회전식 가진기를 사하여 실제 현장조건을 재현하는 시험장비를 개발하였고, 주요 구성품에 대해 카운터웨이트의 고장해석을 수행하였다. 두번째로 현장으로부터 필드데이터를 측정하여 수명시험에 활할 수 있도록 하였다. 마지막으로 성능과 수명을 확인하기 위해 가속수명시험법을 개발하였고, 제품의 고장발생 없이 $B_5$ 10,000 시간을 만족하는 가속수명시험을 완료하였다.

Keywords

References

  1. Bosnjak, S. M., Petkovic, Z. D., Atanasovska, I. D., Milojevic, G. Z. and Mihajlovic, V. M., 2013, "Bucket Chain Excavator: Failure Analysis and Redesign of the Counterweight Boom Supporting Truss Columns," Eng. Fail. Anal, Vol. 32, pp. 322-333. https://doi.org/10.1016/j.engfailanal.2013.04.012
  2. Rusinski, E., Czmochowski, J., Iluk, A. and Kowalczyk, M., 2010, "An Analysis of the Causes of a BWE Counterweight Boom Support Fracture," Eng. Fail. Anal. Vol. 17, 179-191. https://doi.org/10.1016/j.engfailanal.2009.06.001
  3. ISO No. 19973-1, Pneumatic Fluid Power - Assessment of Component Reliability by Test - Part 1: General Procedures, 2007.
  4. Heinz, P. and Bloch, F. K. G., 1997, Machinery Failure Analysis and Troubleshooting. (Gulf Publishing Company), pp. 490-493
  5. MIL-STD-810G Environmental Engineering Considerations and Laboratory Tests
  6. Stephens, R. L., Fatemi, A., Stephens, R. R. and Fuchs, H. O., 2001, "Metal Fatigue in Engineering," 2 Edition, John Wiley & Sons.