• Title/Summary/Keyword: Fixed guide

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A Study on Wear of Aluminum Alloy Guide Hole in SSD Tester (SSD 테스터의 알루미늄 합금 Guide Hole의 마모에 관한 연구)

  • Ham, Eung jin;Kim, Moon Ki
    • Journal of the Semiconductor & Display Technology
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    • v.21 no.2
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    • pp.19-24
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    • 2022
  • The purpose of this research is to determine the hardness of guide hole. A guide pin and a guide hole of SSD(Solid State Drive) tester used to mount SSD in a fixed position accurately. The guide pin and guide hole are worn by friction due to repeated operation, and the wear is concentrated on the guide hole made of weak material rather than the guide pin made of relatively strong material. Because of that reason, it is often overdesigned in the design stage because it can lose its function. If the guide hole is made soft, the manufacturing cost will decrease, but the accuracy will decrease due to wear caused by repeated friction. If the guide hole is manufactured excessively, the manufacturing process becomes complicated and the manufacturing cost increases. It is essential to design a guide hole, but since there is no standard or verified data that can be referenced, it is difficult to design. Experimental device which guides in the same way as the SSD tester is used for this research, and three types of anodizing state are experimented for different hardness. Also, weight of COK(Change over Kit) were analyzed by measuring the wear amount and state of the guide hole according to the number of repeated attachment and detachment.

2-Dimensional Flow Analysis of Impulse Turbine for Wave Energy Conversion (파랑에너지 변환용 충동터빈의 2차원 유동해석)

  • ;;;;;T. Setoguchi
    • Proceedings of the Korean Society of Marine Engineers Conference
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    • 2001.05a
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    • pp.21-27
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    • 2001
  • This paper describes numerical analysis of the impulse turbine with fixed guide vanes, a high performance bi-directional air turbine having simple structure for wave energy conversion. The numerical analysis of the 2-dimensional incompressible viscous flow based on the full Reynold-averaged Navier-Stokes equations which was made to investigate the internal flow behavior. Numerical results are compared with experimental data obtained by T.Setoguchi laboratory. As a result, as suitable choice of design factor has been clarified with the understanding of the internal flow from the numerical analysis.

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Fixed Prosthetic Restoration in an Edentulous Patient with NobelGuideTM System (양악 무치악 환자에서 NobelGuideTM 시스템을 이용한 고정성 임플란트 보철수복)

  • Shin, Hyoung-Joo;Kim, Dae-Gon;Cho, Lee-Ra;Park, Chan-Jin
    • Journal of Dental Rehabilitation and Applied Science
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    • v.25 no.3
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    • pp.243-253
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    • 2009
  • This report described a technique utilizing a computer-aided design (CAD) /computer-aided machining (CAM) - guided surgical implant placement and prefabricated fixed complete denture for an immediately loaded restoration. A patient with an edentulous maxilla and mandible received 6 implants in maxilla and 6 implants in the mandible using CAD/CAM surgical templates. Prefabricated provisional maxillary and mandibular implant supported fixed prostheses were connected immediately after implant installation. Provisional prostheses were evaluated for aesthetics, function during 6 months. Definitive prostheses were fabricated.

Design and Machining Precision Evaluation of Pneumatic Clamping Type Guide-bush System (공압식 소재물림 가이드부쉬 시스템의 설계 및 가공정도 평가)

  • Lee, Jae-Hoon;Yi, Su-Min;Park, Seong-Hun;Lee, Shi-Bok
    • Journal of the Korean Society of Manufacturing Technology Engineers
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    • v.19 no.6
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    • pp.859-866
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    • 2010
  • Generally, a fixed type guide-bush system is installed during machining miniature work-pieces with high precision in the multi-task CNC lathe. But a conventional guide-bush system does not provide a constant clamping force under the condition of varying work-piece diameters. It is important to maintain a constant clamping force for guaranteeing machining precision. This paper proposes a new guide-bush system with a pneumatic clamping device for the CNC Swiss-turn lathe to keep constant clamping force with changes in work-piece diameters. Through performance tests, new clamping system developed in the study showed better machining precision at the cost of a small increase in the temperature of the system than conventional systems due to an increase in the frictional heat and a change in the heat transfer route.

An Experimental Study on Heat Transfer Characteristics of a Thermal Diode Type Enclosure with a Guide Vane

  • Kim, Suk-Hyun;Jang, Young-Keun
    • International Journal of Air-Conditioning and Refrigeration
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    • v.9 no.4
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    • pp.10-16
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    • 2001
  • An experimental study for free convective heat transfer in a thermal diode type enclosure is presented. The thermal diode is a device which allows heat to be transferred in one direction by convection due to density difference of the fluid, and consists of a rectangular-paralle-logrammic enclosure with a guide vane. It is used as heat collection system of solar energy due to its simple construction and low cost. Experimental parameters were guide vane thickness, the inclination angles of the parallelogrammic enclosure, and the lengths of the rectangular enclosure part. The parameter range of the flux Rayleigh numbers was $2.4\times{10}^8$~$9.8\times{10}^8$. The heat transfer rate of this system was shown 10~47% higher than that of other earlier research results without the guide vane. The correlation for fixed $\phi=60^\circ$ was obtained, Nu=0.0037(Ra^*)^{0.429}(d^*)^ {0.050}(Lr/H)^{0.0415}$.

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Heat/Mass Transfer for Impingement/Effusion Cooling System with Circular Guide (원형가이드 설치에 따른 충돌제트/유출냉각에서 열/물질전달 특성)

  • Hong, Sung-Kook;Cho, Hyung-Hee
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.30 no.12 s.255
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    • pp.1147-1154
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    • 2006
  • An experimental investigation was conducted to enhance the heat/mass transfer for impingement/effusion cooling system when the initial crossflow was formed. For the improvement of heat transfer, the circular guide is installed on the injection hole. At the fixed jet Reynolds number of 10,000, the measurements were carried out for blowing ratios ranging from 0.5 to 1.5. The local heat/mass transfer coefficients on the effusion plate are measured using a naphthalene sublimation method. The result presents that the circular guide protects the injected jet from the initial crossflow, increasing the heat/mass transfer. The heat transfer of stagnation region is hardly changed regardless of the blowing ratio. The secondary peak is obviously formed by flow transition to turbulent flow. At high blowing ratio of 1.5, the circular guide produces $26{\sim}30%$ augmentation on the averaged heat/mass transfer while the case without circular guide leads to the low and non-uniform heat/mass transfer. With the increased heat/mass transfer, the installation of circular guide is accompanied by the increase of pressure loss in the channel. However, the pressure drop caused by the circular guide is lower than that for other cooling technique with the circular pin fin.

Die Design for Shape Drawing to Improve the Dimensional Accuracy of a Hollow LM-Guide Rail (중공형 LM-Guide Rail의 치수정밀도 향상을 위한 형상인발 금형 설계)

  • Park, J.H.;Lee, K.H.;Kim, S.M.;Kim, H.J.;Kim, S.J.;Kim, B.M.
    • Transactions of Materials Processing
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    • v.24 no.5
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    • pp.340-347
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    • 2015
  • Multi-pass shape drawing is used to manufacture long products of arbitrary cross-sectional shapes. This process allows smooth surface finishes and closely controlled dimensions of the cross-sectional shape. Tube shape drawing for hollow type products provides material savings and weight reduction. The intermediate die shapes are very important in multi-pass tube shape drawing. In the current paper, the design method for the intermediate dies in a tube shape drawing process is developed using a die offset for corner filling (DOCF) method. Underfill defects are related to the radial velocity distribution of each divided section in the deformation zone. The developed intermediate die shape design was applied to the two-pass tube shape drawing with fixed mandrel for manufacturing a hollow linear motion (LM) guide rail. The proposed design method led to uniform and steady metal flow at each divided section. FE-simulations and experiments were conducted to validate the effectiveness of the proposed method in multi-pass tube shape drawing process.