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한국기계기술학회지 [Journal of the Korean Society of Mechanical Technology]

간행물 정보
  • 자료유형
    학술지
  • 발행기관
    한국기계기술학회 [Korean Society of Mechanical Technology]
  • ISSN
    1229-604X
  • EISSN
    2508-3805
  • 간기
    격월간
  • 수록기간
    1999~2019
  • 등재여부
    KCI 등재
  • 주제분류
    공학 > 기계공학
  • 십진분류
    KDC 550 DDC 621
제18권 제2호 (23건)
No

<학술연구>

1

노즐 출구에서 외부 유체 조건에 따른 유동의 가시화 특성

전민경, 김경련, 박종호

한국기계기술학회 한국기계기술학회지 제18권 제2호 2016.04 pp.165-170

※ 기관로그인 시 무료 이용이 가능합니다.

Computational fluid dynamic (CFD) could analysis the flow characteristics in the nozzle exit with fluid condition variation. Consequently, the purpose of this paper is to show that the fluid temperature and velocity field formed in the nozzle exit dominates the understanding for flow phenomenon. High fluid velocity can cause such a high temperature in the test gas that dust the particles grow. For this reason the flow conditions with air-air, air-vapor as test gases were used in this paper. The most important result to come from the CFD was the existence of the shock wave structure which was a dominant influence on the flow characteristics in the nozzle exit. Specially, It has an advantage to confirm the normal shock wave location because the temperature field variation of the flow distinguish clearly through mach disc.Also, the temperature through normal shockwave is at around 2.0 times higher than in atmosphere fluid condition. Consequently, this can be used as a good technical background for the design of rocket engine.

4,000원

2

파워스티어링 오일탱크의 유체-구조 연성해석에 관한 연구

장병춘, 양동욱

한국기계기술학회 한국기계기술학회지 제18권 제2호 2016.04 pp.171-176

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Most of the commercial vehicle steering system is hydraulic. In this system, Breakage and leakage of oil tank is the cause of serious problems to inhibiting the vehicle direction control of the driver. Inthis paper, FSI(Fluid-Structure Interaction) analysis was performed considering the sloshing of oil in the tank for structural safety evaluation of the power steering oil tank. Additionally, vibration analysis of simple and fast evaluation method was performed by assuming the fluid to mass. As a result, sloshing analysis of oil in the tank was confirmed from the FSI vibration analysis, and it could get the distribution of the flow pressure 8.2kPa~-5.5kPa. Second, stress change of the FSI vibration analysis results was greater in the 33.6MPa to 0.25MPa during the transitional period 2cycle, then it showed a stable result. Third, maximum stress of FSI vibration analysis considering sloshing of the oil was 2.22MPa. maximum stress of vibration analysis assuming the fluid to mass was 4.50MPa and 103% higher than the FSI vibration analysis, but the oil tank was safely evaluate structurally safety factor 14.1. Finally, without the FSI vibration analysis by applying a weight of 0.5 to the result of vibration analysis assumes fluid to mass, it could be obtained results similar to FSI vibration analysis.

4,000원

3

냉간 확장한 구멍을 지닌 강판의 잔류응력해석 및 피로수명에 관한 연구

고승기, 연문흠

한국기계기술학회 한국기계기술학회지 제18권 제2호 2016.04 pp.177-183

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The residual stress analysis and fatigue test of a steel plate with a hole were performed in order to investigate the effects of the cold expansion on the fatigue life of the plate. The cold expansion methodis a metal forming process by expanding a hole in order to induce compressive tangential residual stresses near the hole. In this research, a S45C steel plate of 3.2 mm thickness with a hole of 4.318 mm diameter was cold expanded by using a mandrel, resulting in a degree of expansion 1.47%. A significant amount of compressive tangential residual stress of 502 MPa at the hole surface was calculated using the finite element analysis and the compressive residual stress was more widely spreaded in the entry and exit planes than the mid plane in the plate thickness. The compressive tangential residual stresses showed a very beneficial influence on the fatigue life of the plate by increasing 1.2 to 2 times longer lives compared to the plate without cold expansion, depending on the applied load levels. Fatigue crack initiated and propagated at the hole surface of the mandrel entrance region, where relatively lower magnitude of compressive residual stress was found than the other region.

4,000원

4

스풀 밸브의 거동에 따른 경계 조건 변경에 관한 연구

이태근, 김태규, 김대호, 민상기

한국기계기술학회 한국기계기술학회지 제18권 제2호 2016.04 pp.184-191

※ 기관로그인 시 무료 이용이 가능합니다.

Various types of hydraulic valves are used to control hydraulic equipment including construction equipment such as excavator, crane. etc. The main control valve is a core component, to complex controlfluid flow or supplying constant fluid pressure to actuator in accordance operating environment. Excessive flow rate is drained for safety of hydraulic system by main control valve. In this study, the scheme program to change the boundary condition according to behavior of the spool valve is developed. Using this results, the CFD analysis are accomplished.

4,000원

5

심해 퇴적물 저층충격시험에 따른 DSSRS 주변의 유동특성

채용배, 임성진, 허진석, 이상호

한국기계기술학회 한국기계기술학회지 제18권 제2호 2016.04 pp.192-199

※ 기관로그인 시 무료 이용이 가능합니다.

Seawater flow characteristics around deep-sea sediment resuspension system was analyzed using CFD simulation. Seawater flow is influenced by migration velocity of DSSRS and the resuspension system with disturbance device. Especially complicated flow field is generated with discharged flow in the vertical direction, and there is large variation of seawater velocity near the system with vortex flow. Turbulent kinetic energy near the system increases 2~6 times, and its variation is also affected by the operation condition of the disturbance device. The results of this study are expected to be useful in evaluating the environmental effects of the suspended solid matters which are generated in the deep sea sediment disturbance process.

4,000원

6

재료특성을 고려한 자동차 시트프레임의 변형량 및 응력해석에 관한 연구

이규성, 윤준규

한국기계기술학회 한국기계기술학회지 제18권 제2호 2016.04 pp.200-207

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In this study, analysis on the stiffness of the headrest, the stiffness of front-rear load and the torsion of cushion frame was performed using finite element method in order to investigate the properties of the stress-deformation by material characteristics according to the test requirements of FMVSS (Federal Motor Vehicle Safety Standard). The results are shown that AZ31 (Mg alloy) and A365 (Al alloy) with low modulus of elasticity and density have higher strain rate than steel in terms of stress-deformation and meet the standards for safety within 108 mm of the maximum amount of deformation. Considering it’s safety and durability, however, the selection of AZ31 for light weight seems difficult to gain the reliability because it causes an excessive deformation, and therefore it is not expected to be used for recliner where stress is concentrated and also the bracket linking rail and cushion frame.

4,000원

7

초소수력 발전용 튜고 수차의 개발

신준, 이태연

한국기계기술학회 한국기계기술학회지 제18권 제2호 2016.04 pp.208-213

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Pico hydropower, which refers to generation under 5kW, has been adopted in many places in the world as a cost effective and reliable power supply. The turbine units are important components for picohydropower and must be portable, simple to maintain. In this study, therefore, Turgo turbine units were developed which reported to be reliable, robust and able to operate efficiently over a range of flow rates. A 2D steady-state mathematical model was developed to calculate the performance and design the optimal geometry of Turgo runner. Also, a laboratory-scale simulator was constructed to test the operating performance and experiments were carried out to determine the effect on turbine efficiency of variation in speed and jet diameter. Under the best conditions, developed Turgo turbine efficiency was observed to be over 90% at a speed of 900rpm.

4,000원

8

CFRP 샌드위치 복합재와 알루미늄 폼 코어 CFRP 샌드위치 복합재에 대한 충격 파괴 연구

이정호, 조재웅

한국기계기술학회 한국기계기술학회지 제18권 제2호 2016.04 pp.214-219

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In this study, the fracture property of impact absorption is investigated using the carbon fiber composite material. And this property is compared with the carbon fiber composite material with aluminum foam. Carbon fiber composite material has the high specific strength and rigidity and the superior durability and fatigue life and light weight. On the ground of these properties, this material hasbeen used widely at the fields of airplane, national defence industry, vehicle and the various industrial areas. Aluminum foam can also be applied at the various areas as it is the material with the superiorproperties. And this foam is the material which can solve the problem on the light weight of particular product. At the condition of the impact energy of 20J, the maximum loads of CFRP sandwich composite and CFRP sandwich composite with aluminum foam core are shown to be 5.7 kN and 6.5 kN respectively. In case of maximum energies, these values are shown to be 19 J and 17.5 J respectively. At the impact energy of 50 J, the maximum loads of CFRP sandwich composite and CFRP sandwich composite with aluminum foam core are shown to be 7 kN and 8.8 kN respectively. In case of maximum energies, these values are shown to be 43 J and 48 J respectively. At the impact energy of 80 J, the maximum loads of CFRP sandwich composite and CFRP sandwich composite with aluminum foam core are shown to be 9.2 kN and 11 kN respectively. In case of maximum energies, these values are shown to be 70 J and 63 J respectively. As the result of this study, the mechanical properties are investigated through the impact experiments on the composites composed of the closed aluminum foam and the carbon fiber reinforced plastic used frequently as absorbents.

4,000원

9

지역별 외기온도 및 일사량을 고려한 통신쉘터용 냉방용량 산정에 관한 연구

권재욱, 김종현

한국기계기술학회 한국기계기술학회지 제18권 제2호 2016.04 pp.220-225

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Shelter that communication equipment and on-equipment material are mounted on is transported by airplane, vehicle and has a function such as waterproof and shielding EMI. Maintaining proper inside temperature of shelter is important in order to operate equipment. Accordingly proper cooling capacity of cooling equipment which installed on the shelter is important for equipment and operator. To calculate proper cooling capacity, There are some considerations such as environmental factors and equipment in the shelter. In Korea solar irradiation and outdoor temperature is difference in accordance with geological characteristic. Also electric equipment mounted on the shelter is increased by development of technology. But the capacity of air conditioner is not changed thus there is a problem about operating equipment. In this paper, Compare cooling capacity of shelter when using air conditioner that is not enough cooling capacity and calculate proper cooling capacity to consider geological solar irradiation and outdoor temperature.

4,000원

10

저압함침법을 이용한 Ni 과 Ni-Cr으로 강화된 AC8A 복합재료의 마모특성

Kelimu Tulugan, 황규완, 박원조

한국기계기술학회 한국기계기술학회지 제18권 제2호 2016.04 pp.226-232

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Ni and Ni-Cr reinforced Al alloy (AC8A) composites were fabricated by low pressure infiltration process. Porous Ni was applied as preform. Ni reinforced AC8A composites were fabricated under 0.3 MPa at 650, 700 and 750 degrees centigrade, respectively, while Ni-Cr reinforced AC8A composites were fabricated under low pressure limited to the maximum of 0.5 Mpa at 750, 800 and 850 degrees centigrade, respectively. Microstructure and phase composition of the composites were evaluated by optical microscope, X-Ray diffraction (XRD), electro-probe micro analyzer (EMPA). Intermetallic compounds Al3Ni and CrSi were observed in the composites. The results indicate that the grain size has been increasing with the increase of the infiltration temperatures. However, the wear resistance of Ni/AC8A and Ni-Cr AC8A peaked at 650 degree centigrade and 800 degrees centigrade, respectively. In addition, based on the wear characteristics and wear surfaces, Ni-Cr/AC8A composites have a better wear resistance than Ni/AC8A composites and AC8A.

4,000원

11

체결 압력이 서로 다른 적층각도를 지닌 CFRP 판넬의 파괴에 미치는 영향에 대한 연구

황규완, 조재웅

한국기계기술학회 한국기계기술학회지 제18권 제2호 2016.04 pp.233-238

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As CFRP with only a single material shows the various fracture properties, it has been applied to the many areas through the whole industry. The method bonding with adhesive has been recommended toapply the CFRP to structure. But it is inevitable that the mechanical joints with bolt, nut and rivet have been used sometimes. This study investigates the effect that these joints influence the CFRP panelthrough the analysis result. The analysis models as CFRP panels with the thickness of 5 mm have four kinds of layer angles which are 30°, 45°, 60° and 75°. The fracture property is examined when thepressure by the mechanical joint is applied to the upper panel. As the joint pressure is distributed most effectively in case of the layer angle of 60°, it is shown that this pressure becomes lower and the deformation of panel becomes lowest. On the basis of this study result, it is thought that the foundation data for the design of CFRP structure can be provided and contributed to the safety design of structure.

4,000원

12

오일펌프 내 내접기어 이 수 변화에 따른 성능 분석 연구

김건형, 이동렬

한국기계기술학회 한국기계기술학회지 제18권 제2호 2016.04 pp.239-244

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Recently, car pump market is positively growing in emerging countries as well as advanced countries. A increasing attention is recently drawn to electric vehicle but, still commercialization is expected to take a long time. This research is to study on the performance analysis for change in number of teeth of internal gear oil pump with three different numbers of teeth in the inner gear. After measuring real design features, modeling, velocity distribution and pressure distribution are conducted numerically. Pressure changes and volumetric efficiencies are compared with three different cases in order to analyze the performance for inner gears. Finally, optimum volumetric efficiency is determined with the sequence of case 1, case 2, and case 3.

4,000원

13

디젤기관에서 연료 성분 변화에 따른 연소특성 연구

김홍석, 최승훈

한국기계기술학회 한국기계기술학회지 제18권 제2호 2016.04 pp.245-249

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Our environment is faced with serious problems related to the air pollution from automobiles in these days. In particular, the exhaust emissions from the diesel engines are recognized main cause whichinfluenced environment strong. In this study, the potential of biodiesel fuel and oxygenated fuel (ethylene glycol mono-n-butyl ether; EGBE) was investigated as an effective method of decreasing the smoke emission. The smoke emission of blending fuel (EGBE 0~20 vol-%) was reduced in comparison with diesel fuel and it was reduced approximately 64% at 2000 rpm, full load in the 20% of blending rate. But torque and brake specific energy consumption (BSEC) didn't have no large differences. But, NOx emissions from biodiesel fuel and EGBE blended fuel were increased compared with diesel fuel.

4,000원

14

CNT-Polyamide 복합재의 전기/열 전도도 및 인장강도변화에 관한 연구

김경재, 박영수, 송준혁, 강신재, 양성모

한국기계기술학회 한국기계기술학회지 제18권 제2호 2016.04 pp.250-255

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The effect of CNT diameters on properties of CNT-polyamide composites was investigated such as electrical conductivity, tensile strength and thermal conductivity. To get different diameter distributions of CNTs, several portions of Mo and Fe in Mo-Fe/MgO catalysts were synthesized by a combustion method at 600℃. And all CNTs growed at 900℃ with 3 SLM methane and 1 SLM hydrogen for 40min. Four kinds of CNTs with different diameter distributions, such as 1~3nm, 3~7nm, 7~13nm, and 10~30nm, were selected to make CNT-polyamide composites. Each composite was manufactured by a solution mixing using bar-type ultra-sonicator in the CNT portions from 1phr to 50 phr. And electrical conductivity, tensile strength, and thermal conductivity were measured. Three properties of CNT-polyamide composite, manufactured with 10nm diameter, were more excellent compared to other composites, with electrical conductivity 10 Ω at 7phr, thermal conductivity 2.4.W/mK at 40phr, tensile strength 60MPa at 30phr. CNTs with a diameter of 10nm were superior to other diameters for the multi-functional composite such as CNT-polyamide composites.

4,000원

15

소음지도를 이용한 금속재료품 제조공정의 소음저감 순위 결정

김병삼

한국기계기술학회 한국기계기술학회지 제18권 제2호 2016.04 pp.256-260

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Assessment of noise exposed population is to check the environment noise level and social influence in order to reduce the risks such as annoyance and disturbance that are generated by environmental noise. Also, this method suggests the preferential noise abatement policy and action plan by accurately finding the area that the noise causes harmful effect to human health. Recently, a noise map, which can predict noise in comprehensive area, is used for the assessment of noise exposed population, breaking from the methods using existing measures. In particular, countermeasure for noise can be considered more effectively by using assessment methods of noise exposed population for specific noise level, area, and building types which are the main input factors in noise maps. In this study, we propose noise reduction ranking decision at manufacturing process of metal material products due to noise map.

4,000원

<생산기술>

16

PFA 라이닝 하단 드레인 볼 밸브 개발

김봉석

한국기계기술학회 한국기계기술학회지 제18권 제2호 2016.04 pp.261-267

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As the hydrofluoric acid leak at Gumi-si, Gyeongsangbuk-do or hydrochloric acid leak at Ulsan demonstrated that chemical related accidents were mostly caused by large amounts of volatile toxicsubstances leaked due to the damages of storage tank. The purpose of this study was to develop PFA lined bottom drain ball valve for using in semiconductor, LCD manufacturing fields, pharmaceutical and others. For this purpose, modeling and design of PFA lined bottom drain ball valve, casting mold and casting production, design and manufacturing of lining mold, design and manufacturing of lining jig, PFA forming and assembly have been carried out for 50A×25A PFA lined bottom drain ball valve. In addition, a performance test was performed for the pin hole, density, tensile strength, elongation and elastic modulus of the developed prototype. As a result, the performance of the prototype valve satisfies all the objects of this study. Also, the developed valve was a very good performance compared with conventional 50A×25A imported valve with the same size.

4,000원

17

냉간 다단 단조공법을 이용한 상용 A-IMS 핵심 부품의 설계 최적화

민세훈, 박경범, 서현규

한국기계기술학회 한국기계기술학회지 제18권 제2호 2016.04 pp.268-274

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The objective of this study was to investigate the optimal design on the tubular shaft and solid shaft for A-IMS of commercial vehicle. The tubular shaft and the solid shaft were designed by 6 stageprocesses and the results were analyzed by using a finite element analysis method. The coefficient of friction was set to Oil_Cold conditions as referred to the analysis library. It was found that the actual underfill phenomenon was not observed on the tubular shaft and solid shaft. The metal flow of the tubular shaft and solid shaft revealed that the folding phenomenon was not occurred, so there is noproblem in actual production. Principal stress and load characteristics of tubular shaft were higher than those of solid shaft since the tubular shaft have many deformation from stage 1 to stage 3.

4,000원

18

친환경 스테인리스 단열 창호프레임 개발

이태연, 신준

한국기계기술학회 한국기계기술학회지 제18권 제2호 2016.04 pp.275-280

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In response to requests of the global low carbon emission energy-saving building materials and due to the rapid rise in oil prices, we developed the eco-friendly PVC combined with integrated high-performance stainless steel insulated windows frame. We have made a compound chassis for windows composed of stainless and eco-friendly PVC. This compound window chassis makes the most ofstrong points of both materials and shows excellent insulation, airtightness and wing proofing. Heat insulating performance of the developed stainless steel insulated windows is excellent and itmeet the demands for energy saving improvements and housing culture to improve the quality of life. A new beautiful appearance development can improve the performance of highly effective thermal insulationbuilding materials and will contribute to the development of industrial competitiveness and energy-saving building technology areas.

4,000원

19

전술차량 종감속기패드 고정볼트 파손에 관한 연구

이형준, 김종식

한국기계기술학회 한국기계기술학회지 제18권 제2호 2016.04 pp.281-287

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The mobility of the tactical vehicle is important for a mission completion and survivability. During the field operation of the MLRS(Multiple Launcher Rocket System), broken bolt was found in a final reduction gear with oil leakage. It was confirmed that the final reduction gear pad bolt was broken with ductile fracture after inspecting and scanning electronic microscope of the bolt. Furthermore, a finite element analysis on the bolt was conducted with regards to the operating conditions in the final reduction gear. Conducting the analysis, there was a possibility of the bolt being damaged when we put rusty spline and the adhesion of hub thrust pad as input parameters. Finally, improvements on the spline in the shaft are expected in the future by utilizing the result of this study.

4,000원

20

선박의 해치 및 화물 형상 스캔을 위한 3D 레이저 스캐닝 시스템 개발

고석조, 김태훈, 차병수, 박민규, 유기호, 문영근

한국기계기술학회 한국기계기술학회지 제18권 제2호 2016.04 pp.288-293

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Unloading operation by the unloader is dependent on the experience of the operator in the cabin. If the operator receives information about the unloading situation in the process of lifting the bucket, it is possible to prevent the collision of the bucket with the ship structure. In recent years, numerous measurement systems have become available on the market for three-dimensional surveying of objects, but they are very expensive. This study presents a high quality, low cost 3D laser scanning system designed for object recognition. The developed 3D laser scanning system is built on the base of a 2D laser sensor by the extension with a servo motor and a rotation module. In order to evaluate performance of the developed 3D laser scanning system, the developed system was applied to scan a shape of hatch and cargo holder on a cargo ship. Experimental results showed that to obtain a 3D scanning data for the area around the hatch and cargo holder.

4,000원

21

상부금형 변경에 따른 상용 A-IMS 핵심 부품 최적화 설계

민세훈, 서현규

한국기계기술학회 한국기계기술학회지 제18권 제2호 2016.04 pp.294-300

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The objective of this study is to investigate the effect of closed and open type on the load characteristics and amount of waste in tubular shaft and solid shaft for optimal design. The open and closed type were designed by 6 stage processes and applied for analysis. The coefficient of friction was set to Oil_Cold conditions as refer to the analysis library. It is found that the actual underfill phenomenon was not observed on the closed and open type. The metal flow of the closed and open type are revealed that the folding phenomenon was not occurred, thus there is no problem in actual production. The load characteristics are similar from stage 1 to stage 3 due to the same geometry of upper and lower die. However, tubular shaft and solid shaft are decreased 26% and 32% load from stage 4 to stage 6. In case of open type, amount of waste of tubular shaft and solid shaft are each 11g and 14g.

4,000원

22

하도에 따른 도장특성에 관한 시험적 연구

조연식, 김형현

한국기계기술학회 한국기계기술학회지 제18권 제2호 2016.04 pp.301-305

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Tracked vehicles for military application such as tank and armored vehicle are operated in severe conditions of driving on gravel road and muddy water including river-crossing. Thus, coating on suchvehicles requires more robust characteristics of coating in adhesion, corrosion(salt-spray) resistance and water resistance than those of vehicles for civil applications. Currently, coatings applied on the military equipments are mostly based on the U.S. military specification(known as Mil-SPEC). Typical specifications for primer materials for military application are MIL-P-23377 and MIL-P-53022. And for topcoat, coating material of KDS 8010-1004 specification is typically applied. However, as MIL-P-23377 or MIL-P-530224 is applied for primer coating not only on the tank andarmored vehicle at system level but also on the sub-components of these equipments, there has been a need for test data for determining the feasibility of alternatively applying either of these two coatings for primer coat. Therefore, in this study, coating characteristics are compared with respect to these two different primer coating materials so that the feasibility of alternatively applying them is investigated.

4,000원

23

고정밀 이형압연 자동 제조장치 개발

오익수, 김봉석

한국기계기술학회 한국기계기술학회지 제18권 제2호 2016.04 pp.306-315

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Wire rods having various sectional shape are generally used directly in various applications. In the shape rolling, a couple of grooved rollers are used and the groove match the sectional shape of the wirerod. In this 2 roll system, a couple of rollers must be changed whenever the sectional shape of the wire rod is changed, and the frequent changes of roller cause rise of manufacturing cost. In this study, in order to apply a highly precise 4 roll rolling mill developed in previous studies on the shape rolling manufacturing process, the raw wire feeding equipment, 2 roll rolling mill, turks Head rolling mill, largeheat treatment equipment, a steam cleaning equipment, a large winding equipment, cooling equipment, a tension adjustment equipment, designed and manufactured to the main control system. In addition, the problems corrected throughout these various equipments for manufacturing high-precision automatic rolling mill system developed by assembling more than six months and was conducted between complementary and testing process.

4,000원

 
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