• 제목/요약/키워드: steel wire

검색결과 612건 처리시간 0.029초

고강도 저손실 가공송전선의 개발(I) - 기계적 특성 (Development of High Strength and Low Loss Overhead Conductor(I) - Mechanical Properties)

  • 김병걸;김상수;박주환
    • 한국전기전자재료학회논문지
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    • 제18권12호
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    • pp.1152-1158
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    • 2005
  • New conductor is developed by using high strength nonmagnetic steel(NM) wire as the core of overhead conductor. This conductor is called ACNR overhead conductor(Aluminum Conductor Nonmagnetic Steel Reinforced). Formed by the combination of aluminum alloy wire and high strength nonmagnetic steel wire, it has about the same weight and diameter as conventional ACSR overhead conductor. To enhance properties beneficial in an electrical and mechanical conductor during the process of high strength nonmagnetic steel wire, we made a large number of improvements and modifications in the working process, aluminum cladded method, and other process. ACNR overhead conductor, we successfully developed, has mechanical and electrical properties as good as or even better than conventional galvanized wire. Microstructure of raw material M wire was austenite and then deformed martensite after drawing process. Strength at room temperature is about $180kgf/mm^2\~200kgf/mm^2$. NM wire developed as core of overhead conductor shows heat resistant characteristics higher than that of HC wire used as core of commercial ACSR overhead conductor, Strength loss was not occur at heat resistant test below $600^{\circ}C$. Fatigue strength of vibration fatigue is about $32kgf/mm^2\~35kgf/mm^2$ and that of tension-tension fatigue is $90kgf/mm^2\~120kgf/mm^2$ which is $50\~65\%$ of tensile strength.

교정용 BRACKET과 ARCHWIRE 사이의 마찰저항에 대한 비교연구 (COMPARISON OF THE FRICTIONAL RESISTANCE BETWEEN ORTHODONTIC BRACKET & ARCHWIRE)

  • 성현미;박영철
    • 대한치과교정학회지
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    • 제21권3호
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    • pp.543-560
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    • 1991
  • Practitioners are aware of the presence of friction between bracket system and archwire during sliding movement of teeth. Clinically a mesiodistally applied force must exceed the frictional force to produce a tooth movement. The objective of this study were to determine, on a dry condition, changes in magnitude of friction with respect to load, 3rd order inclination (Torque), archwire materials and ligature type. Three wire alloys (Stainless Steel, TMA, NiTi) in two wire sizes (.016, .016x, .022 inch) were examined respect to two bracket system (Straight, Standard), and two ligature type (Metal, Plastic ligature) at three levels of load (100g, 150g, 200g). The results were as follows; 1. Frictional resistance was found to increase with increasing load for S.S., TMA, NiTi. 2. The straight bracket system was exhibited more frictional force than standard bracket system for .016x, .022 S.S. tightly ligated metal ligature. But, torque difference did not increase friction for loose metal ligature & plastic ligature. 3. Regardless of the ligature type, torque and load, stainless steel wire sliding against stainless steel exhibited the lowest friction, and TMA sliding against stainless steel exhibited the highest friction. 4. The loose stainless steel ligature generated lower frictional resistance than plastic ligature in all experimental groups. 5. The following factors affected friction in decreasing order; wire material ligature type, and load.

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신선 속도 향상을 위한 건식 신선 공정의 패스스케줄 설계 (Pass Schedule Design for Improvement of Drawing Speed in the Dry Wire Drawing Process)

  • 김영식;김동환;김병민;김민안;박용민
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 2000년도 추계학술대회 논문집
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    • pp.600-603
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    • 2000
  • In the high carbon steel wire drawing process, the wire temperature increases as the drawing speed is faster in order to increase the production rate in the shop floor. The rapid temperature rise causes the wire fracture in the dry wire drawing process. So, in this paper, the isothermal pass schedule program, which includes the calculation method of wire temperature at each pass, is proposed to prevent the wire fracture due to the temperature rise. Using the isothermal pass schedule program, it is newly proposed the pass schedule design system that prevents the cup-cone defects, improves the elongation of the final products and assures further deformation. As a result, the temperature rise of the wire was decreased and the production rate of the final product is remarkably grown up according to the increase of the final drawing speed than that of the conventional process. Also, the proposed pass schedule design system could give a useful information to the process designer who would design the high carbon steel wire drawing process.

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치아의 활주 이동시 교정용 brackets와 arch wire사이에서 발생하는 마찰 저항력에 관한 비교 연구 (A COMPARATIVE STUDY OF FRICTIONAL RESISTANCES BETWEEN ORTHODONTIC BRACKETS AND ARCH WIRE DURING SLIDING MOVEMENT OF TEETH)

  • 민정미;서정훈
    • 대한치과교정학회지
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    • 제18권1호
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    • pp.155-163
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    • 1988
  • The purpose of this study was to evaluate and compare frictional forces generated between orthodontic brackets and arch wires. Independent variables were chosen for study: arch wire size and shape, arch wire material, bracket width, and second-order angulation between bracket and arch wire. Kinetic frictional forces of stainless steel (0.014', 0.016', 0.018', 0.016' ${\times}$ 0.022', 0.018' ${\times}$ 0.022'), $\beta-titanium$ (0.016' ${\times}}$ 0.022') arch wires were measured on wide and junior edgewise twin brackets (0.018' ${\times}$ 0.022' slot). Instron was used to pull arch wires while $0^{\circ},\;3^{\circ},\;6^{\circ},\;or\;9^{\circ}$ angulation between and wire and bracket was given. The results were as follows: 1. The frictional force of $\beta-titanium$ wire was larger than that of stainless steel wire. 2. The frictional force was generally increased as the size of wire is increased. 3. The frictional force of rectangular wire was larger than that of round wire. 4. As second order angulation was increased, the frictional force was also increased. 5. The frictional force was larger on a wide bracket than on a junior bracket.

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스테인리스 스틸 강선(STS 316Ti)의 웨이브 성형 시 발생되는 금형 치절에 의한 찍임 자국 최소화에 관한 연구 (A Study on the Minimization of Dent Marks due to Mold Tooth Teeth Generated During Wave Forming of Stainless Steel Wire (STS 316Ti))

  • 문현철;배수한;성효경
    • 한국기계가공학회지
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    • 제21권6호
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    • pp.98-106
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    • 2022
  • Among the parts assembled in the gas receiver of a marine engine, the titanium alloy stainless steel (STS 316Ti) wire mesh serving as a filter was broken, and the related part, the turbine fan of the turbocharger, was damaged. In this study, a sample of the grid wire mesh was collected and the cause of breakage was analyzed, and a method of minimizing the dent mark caused by the mold during wire forming, which is one of the most direct causes, was studied. In addition, the optimum mold shape was realized through FEM simulation, and the wire wave molding machine capable of controlling the speed was improved by supplementing the problems of the existing wire wave molding machine, thereby improving durability with minimal dent marks.

고탄소강 다단 신선 와이어의 표면 잔류응력 예측모델 (Prediction Model of Surface Residual Stress for Multi-Pass Drawn High Carbon Steel Wire)

  • 김대운;이상곤;김병민;정진영;반덕영;이선봉
    • 소성∙가공
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    • 제19권4호
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    • pp.224-229
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    • 2010
  • During the multi-pass wire drawing process, wires suffer a great amount of plastic deformation that is through the cross-section. This generates tensile residual stress at surface of drawn wires. The generated residual stress on surface is one of the problems for quality of wires so that prediction and reduction of residual stresses is important to avoid unexpected fracture. Therefore, in this study, the effect of process variables such as semi-die angle, bearing length and reduction ratio on the residual stress was evaluated through Finite Element Analysis. Based on the results of the Analysis, a prediction model was established for predicting residual stress on the surface of high carbon steel(AISI1072, AISI1082). To identify the effectiveness of the proposed model, X-ray diffraction is used to measure the residual stresses on the surface. As the result of the comparison between calculated residual stresses and measured residual stresses, the model could be used to predict residual stresses in cold drawn wire.

Effectiveness of steel wire mesh as a strengthening material for masonry walls: A review

  • Richard Badonbok Lyngkhoi;Teiborlang Warjri;Wanraplang Warlarpih;Comingstarful Marthong
    • Structural Monitoring and Maintenance
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    • 제10권2호
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    • pp.117-132
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    • 2023
  • The most prevalent and oldest type of structure is unreinforced masonry (URM) structures; URM walls are still a widely used construction material in India and many other developing countries due to their simplicity, ease of construction, economic sustainability, and ability to be built with locally available materials. URM walls are significantly weak while carrying lateral loads. The poor performance of URM walls during earthquakes has necessitated investigating an effective method for strengthening a newly built masonry building or retrofitting an old structure. Wire mesh, being cost-effective and easily available, satisfies the requirements to strengthen new and old URM buildings. The use of wire mesh to strengthen and retrofit the URM structure is simple to use, quick to construct, and inexpensive, especially in developing nations where heavy machinery and highly qualified labour are lacking. The current paper reviews the effectiveness of steel wire mesh as a reinforcing material for enhancing masonry strength. The finding gave encouraging results for the field application of wire mesh.

비조질 선재 제품에 대한 소개 및 최근 연구개발 동향 (Introduction of Non-Heat Treated Steel Wire Rod Developed by POSCO)

  • 이유환;김동현;이상윤;이덕락
    • 한국소성가공학회:학술대회논문집
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    • 한국소성가공학회 2009년도 추계학술대회 논문집
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    • pp.137-138
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    • 2009
  • There is a growing interest to replace the commercial steels with non-heat treated steels, which does not involve the spheroidization and quenching-tempering treatment in the steel-wire industry production. However, non-heat treated steels should satisfy high strength and good formability without performing heat treatment. Therefore, it is important to investigate optimum materials showing a good combination of strength and formability after the cold drawing process. In this presentation, non-heat treated steel wire rod produced by POSCO will be introduced and discussed on detail technical concepts.

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STD-11 합금공구강과 P-20 초경합금재의 WEDM 특성에 관한 연구 (A Study on the Characteristics of Wire-Cut Electrical Discharge Machining for STD-11 Alloy Steel and P-20 Tungsten Carbide Alloy)

  • 이재명;허성중;김원일
    • 한국정밀공학회지
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    • 제13권1호
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    • pp.22-28
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    • 1996
  • From the experimental study of Wire-Cut Electric Discharge Machining of STD-11 alloy steel and P-20 tungsten carbide, the characteristics such as hand drum form and discharge gap have been observed and evaluated for various conditions. Hand drum form can be improved when gap have been observed and evaluated for various conditions. Hand drum form can be improved when gap voltage and spark cycle become smaller, thickness become thinner, wire tension become larger and the no of cutting increases. When 60mm thickness tungsten carbide is cut in normal condition, hand drum form becomes larger due to the low conductivity machining allowance become slightly larger when peak discharge current and gap voltage become larger, or wire tension becomes smaller. Under the same condition, machining allowance of tungsten carbide is larger than alloyed steel by 1/100mm.

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