• Title/Summary/Keyword: load coefficient

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Wear Behavior of Al/SiC Composites Fabricated by Thermal Spray Process (2) - Effect of Applied Load on Wear Behavior - (용사법에 의해 제조된 Al/SiC 복합재료의 마모거동 (2) - 작용하중의 영향 -)

  • Lee, Kwang Jin;Kim, Kyun Tak;Kim, Yeong Sik
    • Tribology and Lubricants
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    • v.29 no.5
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    • pp.298-303
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    • 2013
  • In this work, the effect of applied load on the wear behavior of Al/SiC composites was studied. Al/SiC composites were fabricated following the thermal spray process. Dry sliding wear tests were performed on these composites under four different applied loads, i.e., 5, 10, 15, and 20 N. The wear behaviors of the composites under these applied loads were investigated using scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDS). Under applied loads of up to 15 N, the wear rates of Al/SiC composites decreased with an increase in the applied load because of the formation of an adhesion layer on the worn surface. However in the case of an applied load of 20 N, the wear rate was significantly high because the formation and fracture of the adhesion layer were repeated continuously. These results show that the wear behaviors of the tested composites are significantly influenced owing to the applied loads.

A Study on the Load Capacity Characteristics of the Externally Pressurized Air Lubricated Journal Bearings (외압을 받는 공기윤활 저어널 베어링의 부하특성에 관한 연구)

  • 김수태;조강래
    • Transactions of the Korean Society of Mechanical Engineers
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    • v.12 no.2
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    • pp.231-240
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    • 1988
  • An investigation is carried out for the load capacity characteristics of the externally pressurized air lubricated journal bearings both theoretically and experimentally. Theoretical analysis is made using the incremental method and the finite element method, and the discharge coefficient is considered. The experiments are performed for five bearings which are produced according to the rows of supply holes and the presence of poket or step. The results are compared with the numerical results. The present numerical results are in better agreement with the available experimental results than any other earlier numerical results for the bearings having one row and two rows of supply holes with pocket. The present numerical and experimental results show that the bearing with step has larger load capacity than that without step and that the load capacity increases as the clearance ratio increases.

An Evaluation of Plastic Flow Characteristic for local structure of Weldment in Power Plant using SP test and Inverse FEA (역해석과 소형펀치 시험에 의한 발전설비 용접부의 소성유동특성 평가)

  • Baek, Seung-Se;Kwon, Il-Hyun;Kim, Hoi-Hyun;Lee, Dong-Hwan;Yang, Sung-Mo;Yu, Hyo-Sun
    • Proceedings of the KSME Conference
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    • 2004.11a
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    • pp.308-313
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    • 2004
  • SP test has been confirmed the availability, however the application of SP test is hampered because the relation of stress-strain and load-displacement is not determined definitely. This study suggested an evaluation technique of plastic flow characteristic for X20CrMoV121 steel weldment through inverse analysis using SP test and finite element analysis(FEA). From the result, good agreement was found in load-displacement curves obtained from SP test and FEA. Also, The behavior of load-displacement curve from FEA show a rule that load is increase with increasing K(strength coefficient) and displacement is increase with increasing n(work hardening index). From the inverse analysis, true stress-strain curve could be obtained for each local structure of weldment. And the CGHAZ and WM, which showed lower load- displacement behavior, have smaller work hardening index, while FGHAZ have the largest index.

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Development of a Rice Weighing System for Head-Feed Combine (자탈형 콤바인용 벼 무게 측정시스템 개발)

  • Lee, C.K.;Choi, Y.;Jun, H.J.;Kim, H.J.;Lee, S.B.;Ryu, C.S.
    • Journal of Biosystems Engineering
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    • v.32 no.5
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    • pp.332-338
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    • 2007
  • Yield mapping is necessary for precision farming. An on-site rice weighing system for a head-feed combine was developed to measure the total weight of rice grain harvested while the combine was operated. A load cell system was used to monitor rice weights accumulated into the combine grain tank using a load cell. This method gave cumulative grain weight readings as a function of time. The system consisted of a load cell, two supporting brackets, and a computer-based data acquisition system. The weights measured with the system from two fields were compared with those obtained with a commercially available electronic balance. The response of the load cell to varying grain weights was linearly modeled, showing a coefficient of determination of 0.998 and a standard error of ${\pm}4.09kg$.