• 제목/요약/키워드: ring-winding

검색결과 44건 처리시간 0.018초

Experimental Investigation on Relationship of Winding Process Variables and Mechanical Properties for Filament Wound Composites (필라멘트와인딩 복합재의 기계적 특성과 와인딩시 공정변수와의 관계에 대한 실험적 고찰)

  • 윤성호;김준영;황태경
    • Journal of the Korean Society of Propulsion Engineers
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    • 제3권2호
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    • pp.56-65
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    • 1999
  • The relationship of the winding process variables and the mechanical properties of filament wound composites is investigated experimentally. The winding process variables considered are the fiber tensions and the fiber ends. The filament wound ring specimens are fabricated using 3-axis controlled filament winding machine. Two types of carbon fibers, TZ-507 and IZ-40, are used as reinforcements and epoxy for filament winding is used as resin. During the winding process, the fiber tensions are varied from 0.5kgf to 3.0kgf, and the number of the fiber ends are varied from 1 to 6. The fiber volume fractions and the void contents for the ring specimens are measured through the resin digestion. The mechanical properties of the ring specimens are also evaluated by the split disk test. The test results show that the winding process variables affect the fiber volume fractions and the void contents of the ring specimens, which result in the variation of the tensile properties of the ring specimens. Therefore, suitable winding process variables should be applied to maximize the structural performance and the productivity for filament wound structures.

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A Study on the Optimum Evaluation Method for Tensile NOL Ring Specimen Manufactured by Filament Winding Process (Filament winding에 의해 제조된 복합재료 NOL RING시험편의 최적 인장강도 평가법에 관한 연구)

  • 권순철;임철문;배창원;엄수현;김윤해
    • Proceedings of the Korean Society For Composite Materials Conference
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    • 한국복합재료학회 2000년도 추계학술발표대회 논문집
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    • pp.203-207
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    • 2000
  • Filament Winding Process is a comparatively simple operation in which continuous reinforcements in the form of roving are wound over a rotating mandrel. And now well established as a versatile method for storage tanks and pipe for the chemical and other industries . In this study, tensile strength of a filament wound ring specimens were evaluated by split disk test fixture and dress disk test fixture , The results obtained from experiments were compared with the theoretical values obtained by the rule of mixtures. And the purpose of this paper is the suggestion of an appropriate test method for the evaluation of tensile properties of filament wound structures .The tensile strength of a ring specimen tested by the dress disk test showed better agreement with the theoretical values than of a ring specimen tested by the split disk test because the stress concentration in edges of a split disk test fixture is more severe than that of dress disk test fixture. The results showed that the tensile strength of a ring specimen was influenced by the geometry of test fixture, the continuity of fibers, fiber-tension, fiber-end and stress concentration in specimen.

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Studies on Reduction of Yarn Hairiness by Nozzles in Ring Spinning and Winding by Airflow Simulation

  • Rengasamy R. S.;Patnaik Asis;Punekar Hemant
    • Fibers and Polymers
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    • 제7권3호
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    • pp.317-322
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    • 2006
  • Reduction of yam hairiness by nozzles in ring spinning and winding is a new approach. Simulation of the airflow pattern inside the nozzles provides useful information about actual mechanism of hairiness reduction. The swirling air current inside the nozzles is capable of wrapping the protruding hairs around the yam body, thereby reducing yam hairiness. Since production rate of winding is very high and the process itself increases yarn hairiness any method to reduce the hairiness of yarns at this stage is a novel approach. A CFD (computational fluid dynamics) model has been developed to simulate the airflow pattern inside the nozzles using Fluent 6.1 software. In this study, both S- and Z-type nozzles having an axial angle of 500 and diameter of 2.2 mm were used for simulation studies. To create a swirling effect, four air holes of 0.4 mm diameter are made tangential to the inner walls of the nozzles. S- and Z-twisted yams of 30 tex were spun with and without nozzles and were tested for hairiness, tensile and evenness properties. The total number of hairs equal to or exceeding 3 mm (i.e. the S3 values) for yam spun with nozzle is nearly 49-51 % less than that of ring yams in case of nozzle-ring spinning, and 15 % less in case of nozzle-winding, while both the yarn types show little difference in evenness and tensile properties. Upward airflow gives best results in terms of hairiness reduction for nozzle-ring and nozzle wound yams compared to ring yarns. Yarn passing through the centre of the nozzle shows maximum reduction in S3 values.

Development of Flexible Packing Ring in Steam Turbine for Reduction of Leakage by using CFD Flow Analysis (CFD 유동해석을 이용한 누설 저감을 위한 증기터빈용 플렉시블 패킹링 개발)

  • Kim, Jin Hyung;Bae, Jun Ho;Lee, Chang-Ryeol;Kim, Chul
    • Journal of the Korean Society for Precision Engineering
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    • 제30권7호
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    • pp.741-748
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    • 2013
  • A conventional packing ring was designed with a large clearance to prevent damage due to the vibration of the rotor, which can lead to an increase in steam leakage. In this study, a flexible packing ring using winding springs was developed to prevent damage to the rotor teeth by minimizing vibration, while maintaining a smaller clearance than that of conventional rotor designs. Theoretical analysis and finite element analysis (FEA) were used to design the winding spring to satisfy the specified allowable stress limit and minimum load requirements. The shape of the winding spring was designed by applying curves to the center and end parts of a flat spring. Computational fluid dynamics (CFD) analysis was used to predict the leakage of the flexible packing ring. Flow rate measurement tests were performed to verify the leakage reduction efficiency and the reliability of the CFD analysis.

A Study on the Evaluation Method for optimal Tensile NOL Ring Composite Specimen Manufactured by Filament Winding Process-to manufacture and elvaluate the composite turbine blade of wind generator system- (필라멘트 와인딩 공법으로 제조된 복합재료 NOL Ring 시험편의 최적 인장강도의 평가법에 관한 연구 -풍력발전용 복합재료 터빈블레이드 제조 및 평가를 목적으로-)

  • 배창원;권순철;임철문;엄수현;김윤해
    • Journal of Advanced Marine Engineering and Technology
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    • 제25권1호
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    • pp.87-94
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    • 2001
  • Filament winding process is a comparatively simple operation in which continuous reinforcements in the form of roving are wound over a rotating mandrel. And now it is well established as a versatile method for storage tanks and pipe for the chemical and other industries. In this study, tensile strength of a filament wound ring specimens were evaluated by split disk test fixture and dress disk test fixture. The results obtained from experiments were compared with the theoretical values obtained by the rule of mixture. And the purpose of this paper is to suggest an appropriate test method for the evaluation of tensile properties of filament wound structures. The tensile strength of a ring specimens tested by the dress disk test showed better agreement with the theoretical values than of a ring specimen tested by the split disk test because the stress concentration in edges of s split disk test fixture is more severe than the that of dress disk test fixture. The results showed that the tensile strength of a ring specimen was influenced by the geometry of test fixture, the continuity of fibers, fiber-tension, fiber-end and stress concentration in specimen.

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A Study on the Evaluation Method for Tensile Ring Specimen Manufactured by Filament Winding Process (필라멘트 와인딩 공법으로 제조된 링 시험편의 인장강도 평가법에 관한 연구)

  • 배창원;권순철;임철문;엄수현;김윤해
    • Proceedings of the Korean Society of Marine Engineers Conference
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    • 한국마린엔지니어링학회 2000년도 추계학술대회 논문집(Proceeding of the KOSME 2000 Autumn Annual Meeting)
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    • pp.15-20
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    • 2000
  • Filament winding process is a comparatively simple operation in which continuous reinforcements in the form of roving are wound over a rotating mandrel. And it is now well established as a versatile method for storage tanks and pipe for the chemical and other industries. In this study, tensile strength of a filament wound ring specimens were evaluated by split disk test fixture and dress disk test fixture. The results obtained from experiments were compared with the theoretical values obtained by the rule of mixtures in composites . And the purpose of this paper is the suggestion of an appropriate test method for the evaluation of tensile properties of filament wound structures. The tensile strength of a ring specimen tested by the dress disk test showed better agreement with the theoretical values than that of a ring specimen tested by the split disk test because the stress concentration in edges of a split disk test fixture is more severe than that of dress disk test fixture. The results showed that the tensile strength of a ring specimen was influenced by the geometry of test fixture, the continuity of fibers, fiber-tension, fiber-end and stress concentration in specimen.

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A Study on the Optimum Evaluation Method for Tensile NOL Ring Specimen Manufactured by Filament Winding Process (Filament Winding에 의해 제조된 복합재료 NOL Ring시험편의 최적 인장강도 평가법에 관한 연구)

  • 김윤해;권술철;임철문
    • Composites Research
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    • 제14권2호
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    • pp.8-12
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    • 2001
  • Filament Winding Process is a comparatively simple operation in which continuous reinforcements in the form of roving are wound over a rotating mandrel. It is well established and versatile method for storage tanks and pipes for the chemical and other industries. In this study, tensile strength of a filament wound ring specimens were evaluated by a split disk test fixture and a dress disk test fixture. The results obtained from experiments were compared with the theoretical values from the rule of mixtures. The purpose of this paper is the suggestion of an appropriate test method for the evaluation of tensile properties of filament wound structures. The tensile strength of a ring specimen tested by the dress disk test showed better agreement with the theoretical values than those tested by the split disk test because of higher stress concentration in edges of a split disk test fixture. The results showed that the tensile strength of a ring specimen was influenced by the geometry of test fixture, the continuity of fibers, fiber-tension, fiber-end and stress concentration in specimen.

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A Study on the Design Parameters of the Static Ring in the Ultra-high Voltage Non-uniform Electric Field (초고압 불평등 전계에서 정전링 설계변수에 대한 연구)

  • Kim, Jin-Sung;Seo, Min-Seong
    • Journal of the Korea Academia-Industrial cooperation Society
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    • 제21권7호
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    • pp.577-582
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    • 2020
  • Electricity produced at power plants is distributed to consumers through several stages of substations. At this time, an ultra-high voltage transformer is needed in the initial transmission stage to transmit a voltage suitable for each consumer. A high voltage, non-uniform electric field is formed at the end of the winding of the ultra-high voltage transformer, which carries a risk of dielectric breakdown. The winding of the ultra-high voltage transformer is an electrode, which is the key to converting the magnitude of the voltage. A non-uniform electric field is formed along the shape of the winding end, resulting in high electrical stress. The static ring installed at the upper and lower ends of the winding is used to disperse the stress at the winding end. Several variables should be considered when designing a static ring. Among them, this study examined how the curvature of the static ring, the thickness of the insulating paper, the number of barriers, and barrier thickness affect the electrical stress of the static ring using the Finite Element Method. Suggestions to be considered when designing the static ring are proposed through the FEM results.

A Study on the Preocessing of high Runctional Composites and the Evaluation of Its Characteristics (고기능성 복합재료의 제조와 그 특성평가에 관한 연구)

  • 김윤해
    • Journal of Advanced Marine Engineering and Technology
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    • 제22권2호
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    • pp.139-145
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    • 1998
  • Filament winding method is widely used for composite fabrications using low viscosity liquid for-mation and processing asymmetrical structures of pressure vessel pipe rocket motor case etc. The filament winding method is affected by several parameters such as pot life of process time viscosi-ty of resin filament winding temperature and schedules curing condition and post curing condi-tion of resin. To develope high functional composite materials the rotation(5, 15, 20, 30rpm) of the winding machine was controlled by D.C motor. And the wiper to give proper tension was equipped between strand and resin bath. The resin is hooked by the design wiper. The adequate cure schedule was found by DSC. NOL ring test is carried out to investigate the basic physical properties such as design technology. The void contents in filament winding is generally higher than that of the prepreg laminated plate. These high contents of void can make a crack in resin in spite of low deformation. These problem was solved by giving tension in processing. To improve the characteristics of fiber volume fraction void contents resin/fiber bonding the winding speedc is changed under constant tension. It was found that resin impregnation was not different from in fiber contents void contents at the range of 0.5~1kg tension but it was found that resin was not impregnated at the above of 1.5kg tension. In burst test a pure PE liner was failed at a nozzle part under the $14kg/\textrm{cm}^2$ pressure but a pressure vessel of CNG was failed at a cylinder part under the $200kg/\textrm{cm}^2$ pressure.

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Ring Winding의 효과(效果)

  • O, Sang-Se
    • Proceedings of the KIEE Conference
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    • 대한전기학회 1973년도 산학협동세미나 및 학술발표회 초록
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    • pp.124-126
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    • 1973
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