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Life Prediction of Elastomeric U Seals in Hydraulic/Pneumatic Actuators Using NSWC Handbook

NSWC를 활용한 유공압 액추에이터 U 형 씰의 수명예측

  • Shin, Jung Hun (Medical Device Development Center, Daegu-Gyeongbuk Medical Innovation Foundation) ;
  • Chang, Mu Seong (Reliability Assessment Center, Korea Institute of Machinery & Materials) ;
  • Kim, Sung Hyun (Reliability Assessment Center, Korea Institute of Machinery & Materials) ;
  • Jung, Dong Soo (Reliability Assessment Center, Korea Institute of Machinery & Materials)
  • 신정훈 (대구경북첨단의료산업진흥재단 첨단의료기기개발지원센터) ;
  • 장무성 (한국기계연구원 신뢰성평가센터) ;
  • 김성현 (한국기계연구원 신뢰성평가센터) ;
  • 정동수 (한국기계연구원 신뢰성평가센터)
  • Received : 2014.02.21
  • Accepted : 2014.08.24
  • Published : 2014.12.01

Abstract

Even the rough prediction of the product test time before the lifetime test of mechanical component begins would be of use in estimating cost and deciding how to keep up with the test. The reliability predictions of mechanical components are difficult because failure or degradation mechanisms are complicated, and few plausible databases are available for lifetime prediction. Therefore, this study conducted lifetime predictions of elastomeric U seals that were respectively installed in a hydraulic actuator and a pneumatic actuator using lifetime models and a field database based on failure physics and an actual test database obtained from the NSWC handbook. To validate the results, the predicted failure rates were compared with the actual lifetime test results acquired in the lab durability tests. Finally, this study discussed an engineering procedure to determine the coefficients in the failure rate models and analyzed the sensitivity of each influential parameter on the seal lifetime.

제품의 수명시험 전에 소요될 시험시간을 대강이라도 예측할 수 있으면 비용을 측정하여 시험을 어떻게 진행할지 판단하는데 도움이 된다. 기계부품의 경우의 신뢰도예측은 시스템의 고장 혹은 열화 메커니즘이 복잡하고 보편적인 데이터베이스가 존재하지 않기 때문에 수행이 난해하다. 본 연구는 유압 액추에이터와 공압 액추에이터에 각각 설치되는 탄성 U 형 씰을 대상으로 수명예측을 NSWC에서 제안하는 고장물리를 고려한 고장률 모형과 현장 데이터베이스를 활용하여 수행하였다. 그 결과들을 검증하기 위해 예측된 수명과 시험된 수명데이터들을 비교하였다. 본 연구는 고장률 모형에 포함된 각종 계수 값들을 결정하는 과정과 씰의 수명에 영향을 주는 인자들의 개별 민감도를 분석하고 그 미비점을 고찰하였다.

Keywords

References

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