• 제목/요약/키워드: Fastener Hole

검색결과 34건 처리시간 0.029초

인접 홀의 영향을 받는 홀 확장 잔류응력의 유한요소해석 (Finite Element Analysis of the Residual Stress by Cold Expansion Method under the Influence of Adjacent Holes)

  • 김철;양원호;석창성;김대진
    • 한국항공우주학회지
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    • 제31권3호
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    • pp.79-84
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    • 2003
  • 홀 확장법은 홀 주위에 압축 잔류응력층을 생성시킴으로서 균열 발생을 지연시키는 방법으로 항공산업 분야에서 널리 사용되고 있다. 홀 확장 잔류응력의 분포는 홀 확장률, 맨드럴 삽입방향, 재료 물성치 등 여러 가지 홀 확장 피라미터에 따라 달라진다. 홀 확장 잔류응력층의 정확한 파악은 항공산업의 실제 설계에 있어서 매우 중요함에도 불구하고 이에 대한 연구는 상대적으로 부족하였다. 본 연구에서는 유한요소해석을 통하여 두 개의 인전한 홀에 홀 확장법을 적용하는 경우 대한 잔류응력 분포를 구하였다. 연구 결과 두개 홀에 동시에 홀 확장을 하는 경우가 순차적으로 홀 확장으로 하는 경우보다 더 유리한 잔류응력 분포를 얻을 수 있었다.

홀 확장된 판재의 에지마진 변화에 따른 피로특성 연구 (A Study on fatigue Properties with Different Edge Margin for Hole Expansion Plate)

  • 이준현;이동석;이환우
    • 대한기계학회논문집A
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    • 제26권11호
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    • pp.2383-2389
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    • 2002
  • This paper describes an experimental study on fatigue life extension by using cold working process in fastener hole of aircraft structure. Cold working process was applied for A12024-7351 specimens by considering the effect of edge margin on fatigue life. It is generally recognized that cold working process offers a protective zone around fastener hole of aluminum aircraft structure due to the residual compressive stresses which lead to retardation of crack growth. Thus this process provides the beneficial effect of increasing the fatigue life of the component. there by decreasing maintenance costs. It has also been successfully incorporated into damage tolerance and structural integrity programs. Cold working specimens were tested at constant amplitude peak cyclic stresses. Fatigue life of cold working specimen compared with that of specimen fabricated with base material. The increase of fatigue life for cold working specimen is discussed by both considering the effect of residual compressive stresses measured by X-ray diffraction technique and quantitative effect of edge margin.

Single Lap Riveted Joint의 베어링 거동 연구 (Study on Bearing Response of Single Lap Riveted Joint)

  • 허광수;윤성호;정종철;이상진;김정석
    • 한국철도학회:학술대회논문집
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    • 한국철도학회 2005년도 춘계학술대회 논문집
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    • pp.326-331
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    • 2005
  • In this study, bearing response in single lap riveted joint is investigated by menas of single lap shear specimens with different types of adherend and fastener. Single lap shear specimen consists of adherend of SUS403 and carbon fabric/epoxy composite. Rivet of Avdel 2691 with 9.6mm diameter is used. Two types of fastener in single lap riveted joint are considered. One is a single lap shear specimen with single fastener, and the other is a single lap shear specimen with double fasteners. Especially, in case of single lap shear specimen with single fastener, the width of the specimen is varied as 2D, 3D, 4D, 6D at a fixed edge distance of 3D. Also the edge distance of the specimen is varied as 1.0D, 1.5D, 2.0D, 2.5D, 3.0D at a fixed width of 4D. In case of single lap shear specimen with double fasteners, two types of specimen are considered. One is a specimen with the width of 6D and edge distance of 3D. The other is a specimen with the width of 4D and edge distance of 2D. Here D designates the hole diameter for riveted joint.

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가중함수법에 의한 기계적 체결홀에 존재하는 타원호형 관통균열의 음력확대계수 해석 ( I ) - 가중함수법의 전개 - (Stress Intensity Factor Analysis of Elliptical Arc Through Cracks at Mechanical Fastener Holes by Weight Function Method ( I ) - Development of Weight Function Method -)

  • 허성필;양원호;현철승
    • 대한기계학회논문집A
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    • 제25권10호
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    • pp.1659-1670
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    • 2001
  • It has been reported that cracks at mechanical fastener holes usually nucleate as elliptical corner cracks at the faying surface of the mechanical joints and grow as elliptical arc through cracks after penetrating the opposite surface. The weight function method is an efficient technique to calculate the stress intensity factors fur elliptical cracks using uncracked stress field. In this study the weight function method for three dimensional mixed-mode problem applied to elliptical comer cracks Is modified for elliptical arc through cracks and the stress intensity factors at two surface points of elliptical arc through cracks at mechanical fastener holes are analyzed by the weight function method. This study consists of two parts and in part I , the weight function method for elliptical arc through cracks is developed and verified.

가중함수법에 의한 기계적 체결홀에 존재하는 타원호형: 관통균열의 음력확대계수 해석 (II) - 혼합모드 음력확대계수 해석 - (Stress Intensity Factor Analysis of Elliptical Arc Through Cracks at Mechanical Fastener Holes by Weight Function Method (II) - Mixed-Mode Stress Intensity Factor Analysis -)

  • 허성필;양원호;류명해
    • 대한기계학회논문집A
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    • 제25권10호
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    • pp.1671-1677
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    • 2001
  • Cracks at mechanical fastener holes usually nucleate as elliptical comer cracks at the faying surface of the mechanical joints and grow as elliptical arc through cracks. The weight function method for elliptical arc through cracks at mechanical fastener holes has been developed and verified in the part I of this study. In part H, applying the weight function method, the effects of the amount of clearance on the mixed-mode stress intensity (actors are investigated and the change of crack shape is predicted from the analysis for various crack shapes. The stress intensity factors leer inclined crack are analyzed and critical angle at which mode I stress intensity factor becomes maximum is determined.

공정능력을 고려한 체결구 부품의 위치공차 최적화 방법 연구 (A Study on the Optimization of Position Tolerance of Fasteners Considering Process Capability)

  • 이상현;이태근;장성호
    • 대한안전경영과학회:학술대회논문집
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    • 대한안전경영과학회 2008년도 춘계학술대회
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    • pp.417-428
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    • 2008
  • Designers have to consider voice of customer, process capability, manufacturing standards & condition, manufacturing method, characteristics of products to decide tolerances. Especially, in case of position of hole and pin, designers have to consider process capability to decide tolerances. The traditional position tolerances used in a drawing are theoretical values which are allocated to position under the worst case assembling condition that both hole and pin are the maximum material condition(MMC). However, When the process capability is high, more exact product size can be produced under stable manufacturing condition. larger clearance of hole and pin can be allocated. In this point of view, manufacturer could increase the yield by allocating larger position tolerance than theoretical position tolerance of hole and pin considering process capability.

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공정능력을 고려한 체결구 부품의 위치공차 최적화 방법 연구 (A Study on the Optimization of Position Tolerance of Fasteners Considering Process Capability)

  • 이상현;이태근;장성호
    • 대한안전경영과학회지
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    • 제11권1호
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    • pp.75-85
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    • 2009
  • Designers have to consider voice of customer, process capability, manufacturing standards & condition, manufacturing method and characteristics of products to decide tolerances. Especially, in case of position of hole and pin, designers have to consider process capability to decide tolerances. The traditional position tolerances used in a drawing are theoretical values which are allocated to position under the worst case assembling condition that both hole and pin are the maximum material condition(MMC). However, when the process capability is high, more exact product size can be produced under stable manufacturing condition. Larger clearance of hole and pin can be allocated. In this point of view, manufacturer could increase the yield by allocating larger position tolerance than theoretical position tolerance of hole and pin considering process capability.

복합재료 적층판의 기계적 체결부 해석 (A analysis on the mechanical joint of composite laminate)

  • 김성준;황인희
    • 한국항공운항학회지
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    • 제19권4호
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    • pp.12-17
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    • 2011
  • This paper gives a review of finite element model for the analysis of fastening as practical points of view. Different mechanical properties of plate-fastener systems are analyzed. Calculations of the system properties are described as well as the technique of their application in model. Analysis has been performed for calculating the load distribution in multi-joint and the results are compared using the several models. The effects of fastener-hole clearance on the load distribution in multifastener joints are presented. And the stress analysis method have been reviewed for failure analysis of mechanical joint of composite laminate.

홀확장 잔류응력 예측을 위한 유한요소해석 (The Finite Element Analysis for Prediction of Residual Stresses Induced by Cold Expansion)

  • 김철;양원호;고명훈;허성필;현철승
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2000년도 추계학술대회논문집A
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    • pp.470-474
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    • 2000
  • Cold expansion of fastener holes is a mechanical process widely used in the aerospace industry. This treatment leads to an improvement of fatigue behavior due to the developed compressive residual stresses on the hole surface. The residual stress profile depends on the parameters of cold expansion, which are, expanding rate, inserting direction of mandrel, material properties etc. and the method to confirm this profile is only measurement by X-ray diffractometer. Despite its importance to aerospace industries, little attention has been devoted to the accurate modelling of the process. In this paper, Two-dimensional axisymmetric finite element simulations have been conducted for the cold expansion in an aluminium plate in order to predict the magnitude and distribution of the residual stress and plastic deformation. Maximum compressive residual stress could be increase about 7 percent using the 2-step cold expansion method.

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홀확장법과 억지끼워맞춤의 잔류응력 비교를 위한 유한요소해석 (The Finite Element Analysis for Comparision of Residual Stress at Cold Expansion Method and Interfernce Fit)

  • 장재순;양원호;김철;고명훈
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2001년도 추계학술대회논문집A
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    • pp.419-424
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    • 2001
  • The purpose of this study is comparing cold expansion method with interference fit. Cold expansion method and interference fit of fastener hole is using in the aerospace industry. These treatment lead to an improvement of fatigue life to the compressive residual stresses developed on the hole surface. But Research is nothing to about difference effect of between cold expansion method and interference fit. So In this paper, It is shown that Comparing cold expansion method with interference fit. and It is further shown that residual stress distribution according to plate thickness.

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