• 제목/요약/키워드: shear ring

검색결과 133건 처리시간 0.027초

Effect of stiffeners on failure analyses of optimally designed perforated steel beams

  • Erdal, Ferhat
    • Steel and Composite Structures
    • /
    • 제22권1호
    • /
    • pp.183-201
    • /
    • 2016
  • Perforated steel beams can be optimised by increased beam depth and the moment of inertia combined with a reduced web thickness, favouring the use of original I-section beams. The designers are often confronted with situations where optimisation cannot be carried out effectively, taking account of the buckling risk at web posts, moment-shear transfers and local plastic deformations on the transverse holes of the openings. The purpose of this study is to suggest solutions for reducing these failure risks of tested optimal designed beams under applying loads in a self-reacting frame. The design method for the beams is the hunting search optimisation technique, and the design constraints are implemented from BS 5950 provisions. Therefore, I have aimed to explore the strengthening effects of reinforced openings with ring stiffeners, welded vertical simple plates on the web posts and horizontal plates around the openings on the ultimate load carrying capacities of optimally designed perforated steel beams. Test results have shown that compared to lateral stiffeners, ring and vertical stiffeners significantly increase the loadcarrying capacity of perforated steel beams.

Bellows 수축에 따른 축방향응력과 clamp의 전단응력한계를 이용한 진공 system 설계 (Vacuum system design using the shear stress limit of clamp and the axial stress associated with bellows contraction)

  • 정진용;유영군;임진형;김형주;최용섭;주정훈
    • 한국표면공학회:학술대회논문집
    • /
    • 한국표면공학회 2014년도 추계학술대회 논문집
    • /
    • pp.306-307
    • /
    • 2014
  • 진공용 장비의 sealing 방법으로 Cu gasket을 이용한 CF type과 O-ring을 이용한 NW type이 있다. 이중 O-ring을 이용한 sealing 방법에는 clamp를 사용하게 되는데 Al 합금으로 제작된 clamp에 bellows의 수축 시 받는 전단응력과 전단응력한계 이상의 힘을 받았을 때의 clamp 파손에 따른 역압에 의한 TMP 손상 분석.

  • PDF

접착 조인트의 전단 충격특성에 관한 연구 (A Study on the Shear Impact Characteristics of Adhesively Bonded Tubular Joints)

  • 김용하;박상근;김동옥;유용문;전성식
    • Composites Research
    • /
    • 제25권1호
    • /
    • pp.14-18
    • /
    • 2012
  • 구조용 접착제는 알루미늄이나 복합재료 같은 가벼운 재질의 접합에 적용함으로써 자동차의 경량화를 이루어 연비 및 승차감등 성능향상에 큰 효과를 얻을 수 있다. 자동차와 같이 충돌환경에 노출이 되어있는 기계 구조물에 접착제를 적용하기 위해서는 접착제의 충격특성에 관한 연구가 필수적이다. 본 연구에서는 pin-ring 타입의 접착조인트를 이용하여 접착제의 전단 충격특성에 관한 연구를 수행하였으며, 충돌해석을 하기 위해 LS-DYNA를 사용하였다.

유리섬유 보강집성재 볼트 접합부 전단내력 예측 (Estimate of Bolt Connection Strength of Reinforced Glulam using Glass Fiber)

  • 김건호;홍순일
    • Journal of the Korean Wood Science and Technology
    • /
    • 제44권1호
    • /
    • pp.67-74
    • /
    • 2016
  • 유리섬유 보강집성재의 볼트접합부 항복전단내력을 예측하기 위해 인장형 전단시험을 통해 측정된 실측값과 설계기준에 의한 예측값을 비교하였다. 볼트접합부의 항복전단내력 예측식을 위해 층재의 방향별 탄성계수, 포아송비, 전단계수를 측정하였다. 설계기준의 예측식 보정을 위해 유리섬유 보강집성재의 파괴거동을 반영한 파괴인성계수($K_{ft}$)를 적용하여 보정항복전단내력을 비교하였다. 층재의 탄성계수는 섬유방향에 따라 연륜폭, 연륜각과 높은 상관관계를 보였다. 유리섬유 보강집성재의 보정항복전단내력은 직경과 보강재에 따라 실측치와 비슷한 경향을 보였으며, 직물형 유리섬유보강집성재의 볼트접합부가 가장 높은 내력성능을 보였다. 볼트직경과 보강재에 따른 유리섬유 보강집성재 볼트접합부의 항복전단내력은 건축구조설계기준의 제안식을 보정한 예측치가 가장 잘 일치하였다.

구조용 압연강재와 연청동 합금의 반용융 확산접합 (A Semi-solid Bonding between Rolled Steel for Structural Parts and Lead Bronze Alloy)

  • 김우열;박홍일;이길근;서원찬
    • Journal of Welding and Joining
    • /
    • 제18권1호
    • /
    • pp.70-76
    • /
    • 2000
  • A rolled steel for structural parts and lead bronze alloy were bonded each other by a new semi-solid diffusion bonding process to investigate the effect of the process parameters, for example bonding temperature and bonding time, on the interface characteristics, and bonding behavior. It can be possible that manufacture of the bonded steel/lead bronze which has a cylindrical shape with inserted the lead bronze alloy into the steel ring by the diffusion bonding process under the semi-solid condition of the lead bronze alloy without any pressure and flux. It has been know that the control of the amount of the liquid phase in semi-solid lead bronze alloy was very important to obtain soundness interface, since the shear strength of the bonded steel/lead bronze at 850℃ for 60 minutes under the condition of about 40% of the liquid phase in the lead bronze alloy shows maximum value, 210 MPa. The shear strength increases with an increase in bonding time and show maximum value, and then decreases.

  • PDF

체적소성가공에서 마찰법칙이 유한요소해석 결과에 미치는 영향에 관한 고찰 (Consideration on Frictional Laws and their Effect on Finite Element Solutions in Bulk Metal Forming)

  • 전만수;문호근;황상무
    • 한국정밀공학회지
    • /
    • 제13권2호
    • /
    • pp.102-109
    • /
    • 1996
  • Effects of frictional laws on finite element solutions in metal forming were investigated in this paper. A rigid-viscoplastic finite element formulation was given with emphasis on the frictional laws. The Coulomb friction and the constant shear friction laws were compared through finite element analyses of compression of rings and cylinders with different aspect ratios, ring-gear forging, multi-stage cold extrusion and hot strip rolling under the isothermal condition. It has been shown that two laws may yield quite different results when the aspect ratio of a process and the fractional contact region are large.

  • PDF

능동 가진을 이용한 원형 제트에서의 유동 소음 제어 (Control of Flow-Induced Noise from a Round Jet using Active Excitation)

  • 김정우;차성대;최해천
    • 대한기계학회:학술대회논문집
    • /
    • 대한기계학회 2003년도 추계학술대회
    • /
    • pp.798-803
    • /
    • 2003
  • The objective of the present study is to investigate the changes in the acoustic source characteristics and far-field noise propagation in an incompressible round jet at Re=10000 for single-frequency excitations using large eddy simulation and Lighthill acoustic analogy. We apply excitations at a frequency corresponding to the jet-column mode ($St_{D}=0.85$) or maximum growth rate in the shear layer ( $St_{\theta}=0.017$ ). The acoustic source derived from the Lighthill acoustic analogy is the second spatial derivative of the Reynolds stresses. In the case of $St_{D}=0.85$, vortex ring and large scale structures are dominant sources, whereas in the case of $St_{\theta}=0.017$, the main sources are located at an upstream position along the shear layer than in the uncontrolled case. Also, the far-field noise propagates along the axial direction due to excitation.

  • PDF

Comparative evaluation of micro-shear bond strength to different luting procedures of ceramics to dentin

  • Lee, Yoon-Jeong;Park, Sang-Jin;Choi, Kyoung-Kyu
    • 대한치과보존학회:학술대회논문집
    • /
    • 대한치과보존학회 2003년도 제120회 추계학술대회 제 5차 한ㆍ일 치과보존학회 공동학술대회
    • /
    • pp.569-569
    • /
    • 2003
  • I. Objectives The purpose of this study was to evaluate the effort of a modified luting procedure called "dual bonding technique" by compare micro-shear bond strength to different luting procedures of ceramics to dentin. II. Materials and Methods Eighty-four freshly extracted caries-and restoration-free human third molar were embedded in epoxy resin using acrylic ring. Flat superficial occlusal dentin surfaces were obtained, initially using a Low speed diamond saw and exposed detin surface was group with #600-grit SiC paper.(omitted)

  • PDF

분말압축성형용 단일보강링 금형의 최적설계 (Optimum Design of one Stress-Ring Die for Powder Compaction)

  • 신중호;손주리
    • 한국기계연구소 소보
    • /
    • 통권17호
    • /
    • pp.75-82
    • /
    • 1987
  • Shrink-rings (Stress-rings) are used in the fabrication of powder compaction dies to increase the allowable compaction pressures for a given die material. Optimum Procedures are used to insure that the stress distributions in the die and stress-rings ultilize fully the strength available in each of the die elements. Two criteria for the optimum die design are used: Maximum shear stress limit for one-piece dies and zero tensile stress limit for combined dies. Examples for each case are presented in this paper.

  • PDF

KSTAR 토카막 장치에서 TF 자석 구조물의 조립에 관한 검토 (Study on Assembly of TF Coil Structure in KSTAR Tokamak)

  • 김경민;최창호;홍권희;양형렬;유인근;허남일;사정우;김학근;김근홍;김상태;김홍택;양진석;박주식;김재호
    • 대한기계학회:학술대회논문집
    • /
    • 대한기계학회 2003년도 추계학술대회
    • /
    • pp.1262-1267
    • /
    • 2003
  • TF magnet structures are the main structural components in the KSTAR magnet systems to protect the superconducting coils from mechanical, electrical, and thermal loads. TF coil structure supports CS and PF coil system. The inter-coil structure contains adjustable shear keys and conical bolts to provide pre-loading in toroidal direction and to resist against in-plane and out-of-plane forces that are the most critical loads on the TF magnet system. The conical bolts and shear keys are specially designed to assemble easily and to provide a convenient accommodation for a good alignment. The connection plate that is one of the prototype fabrications had been manufactured to study adjustability of conical bolts and shear keys for assembly of TF coil structure. We could measure the misalignments at the keyways and conical holes with the misalignment measuring instrument.

  • PDF