Transactions of the Korean Society of Mechanical Engineers A (대한기계학회논문집A)

The Korean Society of Mechanical Engineers (대한기계학회)
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Sliding Wear Properties of Graphite as Sealing Materials for Cut off Hot Gas

고온차단 기밀용 그라파이트의 고온 미끄럼마모 특성 평가

  • Kim, YeonWook (School of Mechanical Design Engineering, Chungnam Nat'l Univ.) ;
  • Kim, JaeHoon (School of Mechanical Design Engineering, Chungnam Nat'l Univ.) ;
  • Yang, HoYeong (School of Mechanical Design Engineering, Chungnam Nat'l Univ.) ;
  • Park, SungHan (Agency for Defense Development) ;
  • Lee, HwanKyu (Agency for Defense Development) ;
  • Kim, BumKeun (Dept. of Mechanical and Automotive Engineering, Inje Univ.) ;
  • Lee, SeungBum (Dept. of Mechanical and Automotive Engineering, Inje Univ.) ;
  • Kwak, JaeSu (Dept. of Aerospace and Mechanical Engineering, Korea Aerospace Univ.)
  • 김연욱 (충남대학교 기계설계공학과) ;
  • 김재훈 (충남대학교 기계설계공학과) ;
  • 양호영 (충남대학교 기계설계공학과) ;
  • 박성한 (국방과학연구소) ;
  • 이환규 (국방과학연구소) ;
  • 김범근 (인제대학교 기계자동차공학부) ;
  • 이성범 (인제대학교 기계자동차공학부) ;
  • 곽재수 (한국항공대학교 항공우주 및 기계공학부)
  • Received : 2013.03.29
  • Accepted : 2013.09.12
  • Published : 2013.11.01
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Abstract

Sealing structure to prevent flowing hot gas into the driving device, located between the driving shaft and the liner of On-Off valve for controlling the hot gas flow path was studied. Wear occurs due to the constant movement of the driving shaft controlled by actuator on graphite as the sealing material. In this paper, the dynamic wear behavior in high temperature of graphite(HK-6) to be used as sealing material was evaluated. Reciprocating wear test was carried out for the graphite(HK-6) to the relative motion between shaft materials(W-25Re). The results of friction coefficient and specific wear rate according to contact load, sliding speed at room temperature and $485^{\circ}C$ considering the actual operating environment were evaluated. Through the SEM analysis of the worn surface, third body as lubricant films were observed and lubricant effect of third body was considered.

고온의 가스유로를 조절하는 개폐식(On-Off)밸브의 구동축과 라이너 사이에 위치하여 구동장치로의 고온 가스유입을 방지하는 기밀 소재에 대하여 연구하였다. 기밀 소재로 사용된 그라파이트(Graphite)는 구동장치에 의한 구동축의 지속적인 움직임으로 인해 마모가 발생한다. 본 논문은 고온가스 조절 밸브 내의 기밀 소재로 사용된 그라파이트(Graphite, HK-6)에 대한 상 고온 마모 특성을 평가하였다. 구동축의 소재인 레늄합금(W-25Re)에 대하여 그라파이트의 마모 시험을 수행하고 마찰계수와 비마모율을 비교하였다. 상온과 실제 작동 환경인 고온 $485^{\circ}C$에서 미끄럼속도와 접촉하중의 변화에 따른 마찰계수와 비마모율을 평가하였다. 마모표면의 SEM 분석을 통하여 상 고온 마모표면에 관찰되는 third body 를 확인하고 이로 인한 윤활효과를 고찰하였다.

Keywords

References

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