• 제목/요약/키워드: improvement of durability

검색결과 591건 처리시간 0.028초

고속내구성 향상을 위한 자동차용 타이어 프로파일의 설계연구 (A Study on the Design of Automotive Tire Profile for High Speed Durability Improvement)

  • 황준;남궁석
    • 한국정밀공학회지
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    • 제14권12호
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    • pp.135-142
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    • 1997
  • New approach to determine thd design of automotive tire profile was introduced. In this study, design technology for tire profile was combined with a finite element method to improve high speed durability. Static and dynamic behavior analysis of new concept tire was compared with conventional tire profile. To obtain the improved tire performance, appropriate design values, ie. design methodology, section profile selection, material properties, are needed.

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차량 로드 휠의 복합축 평가 프로세스 구축을 통한 내구신뢰성 강건화 및 주행안정성 향상 (Improvement of Durability and Reliability by Developing a Bi-axial Test Process of Road Wheel)

  • 정수식;유연상;김대성
    • 자동차안전학회지
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    • 제8권1호
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    • pp.26-30
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    • 2016
  • The steel road wheel on ventilation holes was cracked in the vehicle durability test. But the component durability test by uni-axial, CFT(Cornering Fatigue Test) and RFT(Radial Fatigue Test) had been satisfied. That is, the uni-axial component test could not forecast the crack of vehicle. Therefore this study developed the bi-axial test mode to reflect a vehicle condition(to reflect both vertical and lateral force simultaneously) based on real load data which was measured in Europe and China and developed CAE simulation too. It reproduced the cracks same as vehicle's and verified by bi-axial test machine in the LBF(Fraunhofer Institute for Structural Durability and System Reliability) durability research center in Germany. Finally this the durability CAE simulation by using HMC(Hyundai Motor Company)'s the bi-axial test mode predicts feasibly the steel wheel's durability performance before vehicle durability test.

FATIGUE DURABILITY ASSESSMENT OF FULL-BEAD OF MLS GASKET USING FINITE ELEMENT ANALYSIS

  • CHO S.-S.;HAN B. K.;LEE J.-H.;CHANG H.;KIM B. K.
    • International Journal of Automotive Technology
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    • 제6권5호
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    • pp.513-517
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    • 2005
  • A full-bead of multi-layer-steel engine head gasket, taking charge of the dynamic sealing of combustion chamber, is susceptible to fatigue failure. The fatigue durability of full-bead was assessed with the finite element analysis results and the high-cycle multi-axial fatigue theory. The assessment aimed to reveal the effects of the forming parameters and dimensions of full-bead. The results show that the selection of embossing parameters producing less deformation of bead plate is beneficial for the improvement of durability while the flatting has marginal influence. The fatigue durability also improves with the increase in the width of full-bead and the radial length of bore-side flat region. However, the dimensional effects are limited due to the occurrence of snap-through.

CFRD 표면 차수벽 콘크리트의 내구성 향상에 관한 실험 연구 (An Experimental Study on the Improvement of Durability for Face Slab Concrete in CFRD)

  • 우상균;송영철;원종필;윤영수
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 2001년도 가을 학술발표회 논문집
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    • pp.1017-1022
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    • 2001
  • Dam concrete for pumped storage power plants should have sufficient durability in repetitive wet and dry conditions and abrasion due to water level fluctuation and also in freezing and thawing resistance as well as permeability capacity. This study presents various experimental results to enhance the durability of face slab concrete in CFRD(concrete faced rockfill dam) by varying the fly ash substitution such as 0%, 15%, 20% and 25% and polypropylene such as 0%, 0.1%. The effect on durability of concrete corresponding to the increasing amount of fly ash and polypropylene was evaluated and the optimum quantity of fly ash and polypropylene substitution was recommended. The results show that 20% of fly ash substitution and 0% of polypropylene were found out to be an optimum quantity to achieve excellent performances in durability for face slab concrete in CFRD.

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댐콘크리트의 내구성 향상에 관한 실험적 연구 (An Experimental Study on the Improvement of Durability of Dam Concrete)

  • 윤영수;원종필;송영철;우상균;송유신
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 1999년도 봄 학술발표회 논문집(I)
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    • pp.415-420
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    • 1999
  • Dam concrete should have sufficient durability in wet and dry repetition and abrasion due to water lever variance and also in freezing and thawing resistance as well as water penetration capacity. This study presents various experimental performance to enhance the durability of face slab concrete in concrete face rockfill dam by varying the fly ash substitution of 0%, 10%, 15% and 20% in cement quantity. The effect on durability corresponding to the increasing amount of fly-ash was evaluated and the optimum quantity of fly-ash subtitution was finally recommended. The results show that 15% fly-ash substituion was found out to be an optimum quantity and demonstrated an excellent performances in durability.

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내구성증진용 혼화제(DIA) 및 부순 잔골재의 복합 치환이 순환잔골재를 사용한 고로슬래그 벽돌의 특성에 미치는 영향 (Effects of Crushed Fine Aggregate and Durability Improvement Agent (DIA) on Blast Furnace Slag-Based Brick)

  • 박경택;손호정;김대건;김복규;한민철;한천구
    • 한국건축시공학회:학술대회논문집
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    • 한국건축시공학회 2011년도 추계 학술논문 발표대회
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    • pp.225-227
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    • 2011
  • This study investigates the effect of crushed fine aggregate and chemical admixture (durability improvement agent, named DIA) on blast furnace slag-based brick. The control brick was made with recycled fine aggregate of 100% and, no cement was used. Test results showed that all specimens developed similar strength, except for the specimen without partial replacement of crushed fine aggregate at 3 days. However, it is interesting to note that this specimen without crushed fine aggregate resulted in the highest strength at 7 days. In addition, the DIA had a major effect on the absorption ratio of brick specimens. For the brick specimens with partial replacement of crushed fine aggregate with 10%, the addition of DIA with only 1% was enough to satisfy the code regulated by KS F 4004.

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타이어 고무 애쉬 치환에 따른 플라이애쉬 혼입 콘크리트의 내구성능 성능 평가 (Evaluation of Durability Performance of Fly Ash Blended Concrete due to Fly Ash Replacement with Tire Derived Fuel Ash)

  • 권성준;윤용식;박상민;김혁중
    • 콘크리트학회논문집
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    • 제28권6호
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    • pp.647-653
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    • 2016
  • 본 연구에서는 FA (Fly Ash)를 20%치환한 배합에 대하여 TDFA (Tire Derived Fuel Ash)를 3.0~12.0%까지 중량 치환하면서 내구성 평가를 수행하였다. TDFA는 열병합발전소에서 열효율을 높이기 위해 폐타이어를 혼소시킨 뒤 발생한 산업부산물로서 국내에서 콘크리트에 적용한 연구는 없는 상태이다. 이를 위해 물-결합재를 50%, FA를 20% 치환한 Control 콘크리트를 제조하였으며, TDFA를 치환하면서 압축강도, 촉진 탄산화 시험, 촉진염해 시험, 공극구조평가를 수행하였다. 압축강도, 탄산화, 공극구조에서는 12%까지 TDFA를 FA와 치환해도 동등이상의 성능을 확보하였다. 특히 염해에 대해서는 TDFA의 치환률의 증가에 따라 뚜렷한 염화물 확산계수의 감소를 나타내어 최종적으로 75.3~70.9%까지 염화물 확산계수가 감소하였다. TDFA를 혼입한 콘크리트 배합시, 워커빌리티의 확보가 가능하다면 TDFA를 혼입한 콘크리트는 내구성 개선에 효과적일 것으로 판단된다.

진동환경에 따른 전기설비의 내구성 향상에 관한 연구 (A Study on Endurance Improvement of Electrical Equipment according to Vibration Environment)

  • 박근석;심재명;이대동
    • 전기학회논문지
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    • 제63권8호
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    • pp.1146-1151
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    • 2014
  • The equipment in ships and railway vehicles are continuously exposed to vibration, and its durability is very important. Therefore, consumers require the verification of the performance of equipment via standardized tests under the given environments to improve and stabilize the performance. In this study, a durability improvement and stabilization plan was proposed, which included the exploratory vibration test, variable frequency test and endurance test for the electrical equipment according to the vibration environment. It is expected that this study results will improve the technological competitive power of the ship and railway-related manufacturers and contribute to the equipment development and export.

플라스틱 온실용 아연도강관의 내식성 증대방법 (Experiment on the Improvement in Corrosion Resistance of Galvanized Steel Pipes for Plastic Greenhouse)

  • 남상운;노상목
    • 한국농공학회:학술대회논문집
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    • 한국농공학회 2005년도 학술발표논문집
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    • pp.175-180
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    • 2005
  • Experiments on the improvement in durability of pipe framework for plastic greenhouse were carried out. Effect of protection treatment such as primer and paint coating for new pipes and old rusted ones were evaluated by change of rusty degree and yield strength. The experiments have been conducted during five years until now but it was too short to find the clear differences. However, there was a little improvement in durability of greenhouse pipes by painting after removal of rust. And also component and corrosion characteristics of pipes being used in greenhouses were analyzed, and several countermeasures for protection from corrosion were reviewed.

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Brake Lining Can be Applied to Super High Speed Vehicle

  • Nakano, Satoru;Maejima, Takashi
    • 한국분말야금학회:학술대회논문집
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    • 한국분말야금학회 2006년도 Extended Abstracts of 2006 POWDER METALLURGY World Congress Part2
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    • pp.1305-1306
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    • 2006
  • A new material was developed to achieve improvement of heat durability, improvement of wear resistance, stability of friction coefficient and reduction in aggression to counterpart, because it is difficult to maintain braking properties by using currently available materials in the train wagons used for high-speed transportation. As a result, the new material showed a stable wear resistance even in the speed range of 350km/h, where improvement was also confirmed in reduction of aggression to counterpart material by more than approximately 10%. This development was adopted for the brake lining in the Taiwan High Speed Rail project.

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