한국기계기술학회지 [Journal of the Korean Society of Mechanical Technology]

간행물 정보
  • 자료유형
  • 발행기관
    한국기계기술학회 [Korean Society of Mechanical Technology]
  • ISSN
  • 간기
  • 수록기간
  • 등재여부
    KCI 등재
  • 주제분류
    공학 > 기계공학
  • 십진분류
    KDC 550 DDC 621
제15권 제5호 (27건)



해양복합온도차발전 취수 배관 경로 선정을 위한 해저 지형 조사

조종영, 정훈, 조준철, 김범주, 이철희, 오진식

한국기계기술학회 한국기계기술학회지 제15권 제5호 2013.10 pp.611-616

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OTEC(Ocean Thermal Energy Conversion) system using the temperature difference between cooler deep and surface ocean waters is one of the renewable energy. But in Korea, OTEC system can not apply except in winter because surface sea water temperature is not enough. C-OTEC(Combined OTEC) system is that utilizes temperature difference between sea water and the condenser of power plants via working fluid. It can be a good alternative in the warm surface sea water for Mid-latitudes region like Korea. In this study, a marine survey using multi-beam echo sounder, single-beam echo sounder and sparker seismic wave is performed and sea water intake pipe line is proposed for the 10kW C-OTEC Pilot Plant.



하수처리용 하이드로포일-팁 교반기에 대한 유동해석

김봉환, 안국찬, 강혁재

한국기계기술학회 한국기계기술학회지 제15권 제5호 2013.10 pp.617-622

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The hydrofoil-tip mixer can be used to create the desired material by mixing the two materials in various industries, especially in the waste water and sewage water treatment. The purpose of this study is to clarify flow characteristics induced by 3 types impellers in a mixing tank by CFD. In this study, flat plate, hydrofoil and hydrofoil-tip type impellers are used and the rotating speeds of impellers are 25, 35, 45 rpm. The results in present study show that hydrofoil-tip type is the most proper impeller for mixing in the waster water treatment tank and reducing required power of rotating impeller. This results can be used for the design of the mixing tank in the waste water treatment system.



엔진의 동적거동을 고려한 크랭크축의 구조해석

최복록, 이경로

한국기계기술학회 한국기계기술학회지 제15권 제5호 2013.10 pp.623-628

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Recently, most of moving parts at automobile engine are required to be lighter and compacter and have high performances such as strength and endurance, etc. In particular, the crankshaft is subject to complex loadings such as shear, bending, and torsional loads as well as inertia and torsional vibration. To investigate critical area and optimize the shape of crankshaft at intial design stage, it is necessary to consider the dynamic effect of crankshaft. This paper carried out structural analysis of engine crankshaft by using multi-body dynamics and multi-axial fatigue analysis.



접착제로 접합된 경사진 이중외팔보의 충돌에 대한 시뮬레이션 해석 및 검증

고등, 조재웅

한국기계기술학회 한국기계기술학회지 제15권 제5호 2013.10 pp.629-633

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Tapered double cantilever beam (TDCB) specimens are the most commonly used test configurations to measure the fracture toughness of composites and adhesive joints. The material used in this study is aluminum alloy. For the impact analysis, load and displacement applied from pin onto end block as well as the crack energy release rate are calculated and compared with the finite element analysis results. The energy release rate increases with the velocity increases. As TDCB model with the same condition as experiment is simulated and analyzed, the fracture behavior can be estimated with the analysis result similar to experiment. The simulation results can be agreed with experimental graph and all experimental data at this study can be verified. These experimental results can be applied into real field effectively. It is found that the energy release rates measured from impact tests on the specimens can be predicted by the finite element model suggested in this study.



이종재료 계면균열의 균열진전거동에 관한 연구


한국기계기술학회 한국기계기술학회지 제15권 제5호 2013.10 pp.635-644

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In this study, the crack initiation and propagation behavior of interfacial crack in bimaterial are discussed. Normal crack opening displacements(NCOD) and stresses are analyzed by finite element method using ANSYS and used for extracting fracture parameters. The energy release rates can not explained the initiation and crack propagation velocity of interfacial crack. Initial velocity of crack propagation is dependent upon the normal and shear stress behind of crack tip. The crack propagation velocity of interfacial crack is very dependent upon the normal and shear stress behind of crack tip. In case of negative shear displacements increase in interfacial crack, initiation delay of crack propagation is dependent upon the negative shear stress ahead of crack tip due to the suppressing of crack opening. In case of positive shear displacements increase in interfacial crack, initiation delay of crack propagation is dependent upon the stress behind of crack tip due to the stress decrease. The fracture toughness increase is due to the initiation delay of crack propagation.



Excitation Characteristics of a PZT Exciter for Thermosonic Non-destructive Testing of Steel Plates

Bu-Byoung Kang

한국기계기술학회 한국기계기술학회지 제15권 제5호 2013.10 pp.645-651

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본 연구에서는 서모소닉 시험을 위한 실용적이고 편리한 PZT 가진 시스템을 구축하고 그 특성을 평가하고자 하였다. PZT 가진기의 성능 평가 및 가진기와 시험체와의 다양한 연결방법의 효과에 대하여 평가하기 위한 실험 을 수행하였다. 실험은 서로 다른 두께를 가진 금속 플레이트를 이용하여 수행되었다. 본 논문에는 실험 장치 및 다양한 연결방법의 성능 시험 결과가 소개되었다. 실험 결과 가진기의 공진 주파수 근처에서 작은 입력 전압과 작은 힘을 이용하여 큰 변형률을 가진 다수의 모드를 가진 할 수 있었고 이 결과는 가진 중에 비선형 진동의 발 생 없이 서모소닉 시험을 위해 충분한 변형률을 얻을 수 있는 가능성을 보여준다. 결과적으로 결함 검출을 위해 작은 크기의 변형률이 필요한 시험체의 경우 작은 PZT 가진기가 간편하고 신뢰성 있는 가진 시스템을 제공 할 수 있다는 가능성을 보여주었다.



타원혼합모형에 의한 폴리머 항력감소 난류유동의 예측

신종근, 박명호

한국기계기술학회 한국기계기술학회지 제15권 제5호 2013.10 pp.653-659

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An improved      model for Newtonian fluids has been extended to predict polymer-induced drag reduction FENE-P fluids. The conformation tensor equation which is related to the polymer stress is adopted from the model form of Resende et al., and the models of redistribution and dissipation rate terms for the scalar   transport equation are considered by the elliptic blending equation. Also, the new model terms for viscoelastic stress work in the turbulent kinetic energy equation and the scalar   transport equation are introduced to consider the polymer additives effect. The prediction results are directly compared to the DNS data to assess the performance of the present model predictions.



진동가진에 의한 엔진 배기매니폴드의 파손에 관한 연구

이경로, 최복록

한국기계기술학회 한국기계기술학회지 제15권 제5호 2013.10 pp.661-666

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This paper presents a method for the assesment of vibration fatigues in engine exhaust system. Analysis technologies by virtual model can reduce the number of physical tests and development cycles. The prediction processes are based on the construction of FE model for the exhaust system, normal mode analysis, and frequency response analysis. The analysis results(1st mode: 152Hz) of eigen frequencies are compared with the modal test results(1st mode: 151Hz). And frequency response analysis for accelerations and stresses at critical locations were also presented. The analysis method could be applied to assess the vibration fatigue for the engine exhaust manifold. As a result, maximum stress occurred at the end of diffuser and its frequency shows around 1st natural frequency of exhaust system. It shows a good agreement between numerical and experimental results.



재료 내에 존재하는 크랙의 방향과 길이에 따른 강도 해석

조호선, 조재웅

한국기계기술학회 한국기계기술학회지 제15권 제5호 2013.10 pp.667-671

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In this study, the property of crack growth in structural steel is investigated according to length and angle of crack at the analysis result of model. Strain energy, deformation and stress obtained by finite element analysis are compared with various configuration of crack. Stress intensity factors as fracture toughness are calculated by the basis of strain energy, deformation and stress. As there are almost no errors by comparing stress intensity factors with those from the standard formula, these calculated factors can be confirmed in order to be applied at real structure. In case cracks or holes at structure are existed, the fatigue damage possibility can be examined by use of this study result.



전기자동차 내부탑재용 On-Board 충전기 설계 및 구현

조명현, 이호영

한국기계기술학회 한국기계기술학회지 제15권 제5호 2013.10 pp.673-678

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Technical developments of electric vehicles have been progressed very actively. Especially there are great technical achievements of battery for the electric vehicles to store energy from the outside source. Also there are numerous efforts for improvement charging infrastructure and charging system of the battery. And that is supporting this technology. For example On-Board Charger (OBC) is a battery charging system attached to the vehicle to operate the car. On-Board Charger is designed in manner of consideration such subjects: control via communication with other vehicle’s controller, improve the reliability as the security part, decrease of the life span of the battery due to temperature change during charging and discharging process, high cost of using parts for the high current rating and limitation of increasing the battery capacity. In this paper, there will be a deep discussion of designing and implementing the On-Board Charger to attach to the vehicles, which has superior cooling quality by effective radiant heat design and vibration and shock resistant design.



전기자동차용 배터리 팩 입구 형상에 따른 냉각 성능


한국기계기술학회 한국기계기술학회지 제15권 제5호 2013.10 pp.679-684

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This analytical work was performed to reveal the effect of inlet geometry of battery pack on the temperature distributions and flow stream line for a electric vehicle. To achieve this, standard k-ε model with wall function was applied and the working conditions of battery pack under different air flow rate and inlet area according to the geometry were estimated. It was revealed that as inlet area was smaller, the flow velocity was faster, and it can't cover the whole area of battery module. In case of two inlet case, the cooling efficiency of air flow is less than that of one inlet case because of low flow rate.



자동차 브레이크 드럼(FCD500)의 단속가공에서 공구수명에 관한 연구


한국기계기술학회 한국기계기술학회지 제15권 제5호 2013.10 pp.685-690

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As the automobile industry has recently developed, the automobile parts processing industry is also increasing. However, as the processing companies don't have their own studies or facilities now, their productivity is low. And they are in difficult situations because they cannot stay economically competitive. This study measured the cutting force, surface roughness, and tool wear of Ductile Cast Iron(FCD500) used in automobile brake modules in automobile parts to try to help harsh realities of automobile parts processing industry. And it drew the result by taking a test to increase productivity of processing companies as interrupted cutting is more used in industrial settings than continuous processing.



아연도금 박판소재의 고출력 레이저 용접조건 최적화에 관한 연구

김지선, 김인주

한국기계기술학회 한국기계기술학회지 제15권 제5호 2013.10 pp.691-696

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Laser welding is high power density welding process which is higher speed and productivity, lower thermal deformation. Recently, zinc coated sheet metal is used for many industrial due to the high corrosion resistance. This study explained that it used DOE(Design of experiment) and mathematical statistics method to optimize the conditions of high power laser welding process for zinc coated sheet metal. Finally, optimal condition for laser welding is selected for zinc coated sheet metal by alteration of welding joint width and gap.



Tb0.24Dy0.76Fe2-xNix 박막 구동기를 이용한 무선 마이크로 광학시스템의 개발


한국기계기술학회 한국기계기술학회지 제15권 제5호 2013.10 pp.697-701

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This paper presents new type magnetostrictive optical systems. The suggested wireless optical systems are developed by using two types of magnetostrictive thin film actuators. The first is a seesaw type wireless-controlled compact optical switch, and another is a comb type TbDyFeNi thin film actuator by silicon micromachining techniques with DC magnetron sputtering. In the seesaw type, TbDyFe films are selectively deposited on the micromachined switch matrix. For the optical switching operation, switch is arranged in a 1×2 array (mirror size of 5mm × 800μm × 50μm) and has different length from the supporting point. Mirrors are also actuated by externally applied magnetic fields up to 0.5T. In the comb type, the effect of Ni content on the magneto-mechanical properties of the Tb0.24Dy0.76Fe2 system is investigated with the effect of deposited film thickness of TbDyFeNi on silicon substrate for wireless microactuator. As results, magneto-mechanical characteristics are investigated. using magnetization and deflected angle variation.



전력선 통신 기반 RFID를 이용한 지능형 모빌랙에 관한 연구

박근수, 최주용

한국기계기술학회 한국기계기술학회지 제15권 제5호 2013.10 pp.703-707

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In a mobile-rack which is applied to shelving or storage units fitted with wheeled traction, 2 step gear ratio and document management system by using RFID based on power line communication are proposed. Each part of the mobile-rack is modeled and then analyzed by finite-element method. Considering the maximum stress and the weight, wheel housing is redesigned. 15.56㎒ RFID module and management program are developed and tested.



EV BLDC 모터 코어의 경량화를 위한 주조방안 성형해석


한국기계기술학회 한국기계기술학회지 제15권 제5호 2013.10 pp.709-715

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The automotive industry in the research and development cost ratio accounted for high technology coefficient of specialization research and development budget. development and adoption of innovative technologies such as new materials technology, electronics technology, information and communications technology and new production systems is a source of competitive products. because permanent magnets without applying an external magnetic field in the BLDC motor drive system parts for EV can be supplied. it has been used in several areas. permanent magnet in the different kinds of motor parts materials is one of the key components. permanent magnet is a relatively fast rate of technological advances, changes in price is considered the fastest. in this paper, the BLDC motor parts produce by the core making method of casting method moulding analysis. moulding density was measured. As a result, the moulding density is measured 7.2~7.5g/cm2 results were excellent.



하이브리드 상용트럭 에어 브레이크 챔버 요소부품의 구조적 해석 연구


한국기계기술학회 한국기계기술학회지 제15권 제5호 2013.10 pp.717-723

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Air Brake chamber is a core fucntional part delivering the brake force to drum brakes in hybrid commercial trucks. This part needs to have leakage prevention and durability for reliable operation. As an actuator by air pressure, there has to be no air leakeage, and because it is operated with high tention power spring, there has high durable spring head, that contacted power spring directly. In this study, a spring head was designed new size on weak points structually and simulated by structual simulation program. And, a flange and body tighten by clamp ring was simlated structual deformation by assembly torque and inner pressure. As a result, new desgned spring head has structual stablilty over 1.7~14.7% and deformation is in proprotion to inner pressure but the assembly torque of clamp ring is not related to deformation.



A Study of the Distribution of Stress in Bellows according to Various Conditions

Kyeong-Ro Lee, Jin-Bong Kim

한국기계기술학회 한국기계기술학회지 제15권 제5호 2013.10 pp.725-730

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When a bellows is subjected to various deformation conditions such as angular rotation, axial displacement or lateral deflection, the stress is produced at each convolution. These deformations play a significant role in the analysis of strength. Because of geometric complex, it is difficult to analyze the mechanical behavior of bellows. The symmetrical deformation problems of the bellows have been discussed in the study. These problems were investigated by the finite element method. The bellows was meshed with 8 node shell elements and elastic analysis was performed. The mesh consists of 112,800 elements and the lateral deflection from 0 to 21mm, the axial displacement from 0 to 6mm and the angle of rotation from 0 to 0.21 degree was applied at the end cap for the boundary condition. The effects of boundary conditions such as the angle of rotation and the lateral deflection on the stress concentration for the bellows was studied. In addition, the relationship between minimum von-Mises stress and angle of rotation and deflection of bellows was obtained.




GPS 시스템 및 센서를 활용한 임베디드 영상처리에 기반한 이동장치의 주행유도

김수용, 이승수, 카밀 지덱, 블라디슬라브 막심

한국기계기술학회 한국기계기술학회지 제15권 제5호 2013.10 pp.731-741

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최근에 개발된 시스템 온칩 프로세서는 통합 성능을 요구하는 작업의 가능성을 제공하였으며, 이러한 작업은 예전에는 우수한 성능을 가진 컴퓨터의 도움만으로 수행 할 수 있는 것이었다. 본 논 문에서는 실제 환경 하에서 자율 이동 장치의 GPS 위치측정을 개선하기 위해 임베디드 영상처리기 법을 활용하는 고급 제어 시스템을 소개한다. 메인 컨트롤 시스템은 Raspberry PI 개발 보드에 통합 된 ARM(SoC.) 아키텍처를 기반으로 한다. 제시한 제어 시스템은 실시간 비디오 캡처, 전력-효율적 이미지 처리 작 업, 예를 들어 (임계 값 처리, 이진화, 모션 감지 등) 및 비디오와 같은 스트리밍 결과 이미지를 처리 할 수 있다. GPS 정밀도는 WAAS(EGNOS) 위성을 활용하여 다만 3 미터의 정밀도를 제공 할 수 있다. 제안한 솔루션은 도로와 보도의 경계를 감지하기 위해 GPS 솔루션 및 임베디드 이 미지 처리를 사용한다. 일부 도로나 통로가 길가의 흰색 선을 제공하지 않기 때문에 제시한 알고리 즘은 길가의 흰색 선을 검출하지 않고 보편적인 도로나 보도를 감지한다. 제안한 시스템은 소형 이 동장치에 사용할 수 있다. 예를 들어, 생산 공간 사이의 긴 거리를 가진 중공업 산업 단지에서 부품 수송을 위한 이동장치 등에 사용할 수 있다.
A recent development in system-on-chip processors provides possibilities of integration performancedemanding tasks, which can be performed only with the help of superior range of computers before. The article introduces advanced control system with embedded image processing to improving GPS localization of autonomous mobile devices in real environment. The main control system is based on ARM (SoC.) architecture integrated in Raspberry PI development board. Presented control systems can handle real-time video capturing, power-efficient image processing operation for example (thresholding, binarization, motion detection, ...etc.) and streaming results images as video. GPS precision can provide only 3 meters precision together with WAAS (Egnos) satellite. Our solution uses GPS solution and embedded image processing to detect border of roads or sidewalks. Our algorithm detects road or sidewalk universally without detection of white line in roadside, because pathways and some roads cannot provide this feature. Control system can be used for small autonomous mobile devices for example parts transport in industrial park of heavy industries, where are long distances between production halls.




HECV용 고연비 인간공학적 전자식 가속페달의 답력 특성에 관한 실험적 연구 (1)


한국기계기술학회 한국기계기술학회지 제15권 제5호 2013.10 pp.743-748

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Electro-accel pedal is needed to raise fuel efficiency by controlled pedal angle signal regardless driver’s willings to fast start or stop pedaling, and to reduce muscle fatigue by designed Ergonomic structure. For this purpose, in this study, we designed new mechanism of accel pedal in a double linkage with two springs to minimize the force of pedaling on main pedal period for HECV in close the future. We have achieved the simulation to dynamic characteristics and experimented to measure the pedal force with proto sample, and confirmed the potentialities this new mechanism.



차압밸브를 사용하는 지역난방 시스템의 2차측 공급수 온도 제어방안에 따른 에너지사용량 실증 비교


한국기계기술학회 한국기계기술학회지 제15권 제5호 2013.10 pp.749-758

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In this study, the actual energy consumption of the secondary side of district heating system(DHS) with different hot water supply temperature control methods are compared. Two methods are outdoor temperature reset control and outdoor temperature predictive Control. While outdoor temperature reset control has been widely used for energy savings of the secondary side of the system, the results show that outdoor temperature predictive control method saves more energy. In general, outdoor temperature predictive control method is lowering the supply temperature of hot water, and it reduces standby losses and increases overall heat transfer value of heated spaces due to more flow into the space. During actual energy consumption monitoring, outdoor temperature predictive control method saves about 19.1% when it compared to outdoor temperature reset control method. Also, it is found that when partial load condition, such as daytime, the fluctuation of hot water supply temperature with outdoor temperature reset control is more severe than outdoor temperature prediction control. So, it proves that outdoor temperature prediction control is more stable even at partial load conditions.



신호처리 기술을 이용한 분산성 파동의 원신호 복원성 연구


한국기계기술학회 한국기계기술학회지 제15권 제5호 2013.10 pp.759-764

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Lamb waves are extensively used in plate-like structure inspection because of their guided nature. However, their dispersive properties often limit their use in flaw detection and other applications. Dispersion weakens and defocuses interrogating Lamb waves and makes it difficult to accurately interpret signals reflected from defects or boundaries. Time reversal (TR) processing can be applied to compensate for the effect of dispersive Lamb waves. Thus, the TR operation will enable the amplification of dispersive Lamb wave signals by signal compression in time. In this study, experiments are performed in order to examine the refocusing and recovering the initial input waveform in the long range propagation of dispersive Lamb waves in a plate. Two different time reversal processes (regular TR and reciprocal TR or inverse filtering) are tested and the experimental results are compared.



가솔린 자동차의 유효방전에너지와 인젝터 파형의 상호 관련성 연구

홍석기, 김철수, 유종식

한국기계기술학회 한국기계기술학회지 제15권 제5호 2013.10 pp.767-771

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The experiment was carried out during no-load condition for analysis of the relativity between MAP, hot film, oxygen, the secondary ignition and injector waveform. The experimental methods using oscilloscope were employed to measure waveform. The relativity between several waveform and the secondary waveform coming from ignition coil were measured in case of three decrepit vehicles. From these results, a summary of the important results are as follows. 1. Through fast acceleration experiments, the response time values of hot film sensor and oxygen sensor was faster than the those of the MAP sensor and oxygen sensor. 2. The values of spark line duration time was largest A, C, B type in the order named. And discharge energy of the secondary ignition waveform was largest A, B, C type 3. The value of effective discharge energy is to be nearly proportional to the spark line duration time. 4. The value of effective discharge energy directly increases as revolutions per minute increase, and the value of spark line duration time decreases as revolutions per minute increase.



다구찌 기법을 이용한 가공성에 따른 최적의 공구선정에 관한 연구


한국기계기술학회 한국기계기술학회지 제15권 제5호 2013.10 pp.773-777

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As the demand for car industry increase worldwide and car models diversify, industry of automobile parts also keep pace and grows day by day. However, since industry of automobile parts is staying small and there are only few study on basic knowledge of productivity, financial competitiveness is greatly insufficient. Among accessory processing, there are more parts such as key home or bolt hole rather than general turning operation, therefore, currently study on intermittence process is exigent. This thesis studied on machinability of Ductile cast iron(FCD 500) which is used for car break desk to help this kind of situation. Also it studied machinability by using Taguchi method which can get the best performance with few tests.




브라운가스를 이용한 디젤 내연기관의 수소혼소 타당성 검토

정훈, 조종영, 이철희

한국기계기술학회 한국기계기술학회지 제15권 제5호 2013.10 pp.779-784

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Hydrogen has the very high heating value by comparing with other fuels and its combustion exhausts no carbon. But hydrogen causes the very high adiabatic flame temperature which generates thermal NOx. In this study, two cases of experiments were performed to compare engine characteristics. First and second cases are for only diesel combustion engine and mixed hydrogen diesel engine respectively. To verify the effect of mixed hydrogen-diesel combustion engine, the exhausted gas from modified dual fuel diesel engine was analyzed. In addition, diesel consumption per kWh for each case was estimated to validate its economic feasibility. By mixing hydrogen with 5kW brown(hydrogen-oxygen mixture) gas generator, the amount of CO(carbon mono-oxide) decreased from 330ppm to 210ppm by improving combustion and the amount of NOx increased from 390ppm to 520ppm by higher temperature of combustion chamber. Diesel consumption per kWh decreased from 450cc to 410cc but actually increased until 480cc because of the power of brown gas generator.



전열 온수히터와 팬코일유닛을 이용한 온실 난방효과

백이, 전종길, 김형권, 윤남규

한국기계기술학회 한국기계기술학회지 제15권 제5호 2013.10 pp.785-789

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Experimental hot-water heating system was consisted of power supply equipment, a hot water storage tank, circulating pump, fan coil unit and a plastic flexible hose. This heating system was manufactured by an electric heater of a power capacity 6kw/h and light-oil hot air heater in control the heating capacity was 5,000kcal/h. As the result, temperature difference due to hot-water heating system and hot air heater in greenhouse showed that air temperature at experimental greenhouse, and comparison greenhouse were 14.8℃, 13.4℃ respectively. It was found that root-zone temperature of experimental plot and control were 22℃, 15℃. Root-zone temperature in the experimental plot was 7℃ higher than that in control. The inlet-outlet water temperature difference of 2℃ and 3℃ corresponded to the difference of the heat exchange of about 3,132kcal/h, 4,916kcal/h, the heat exchange effciency ranged from 54~88% generally. Under the experimental condition, equation heat change(Y) and correlation could be represented as follows : Y = -282.92x2 + 2963.9x -1688.6, R2 = 0.9081. it is suggested to applicate energy of root-zone warming system where energy from the groundwater is extracted and transferred to the water.




친환경 유기농업을 위한 피복작물 진압장치 개발

박수용, 오성모

한국기계기술학회 한국기계기술학회지 제15권 제5호 2013.10 pp.791-796

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In this study, rye, Hairy beaches, pastures long and weighing many organic grazing cover crops can repress the uniforms, and the tractor was designed and built for mounting repression device. And identify appropriate working conditions and job factors and job performance by analyzing the correlation between the test results are as follows. Level 40∼50HP tractor for applying cover crops repression device width 2,400㎜, battling roller diameter is 380㎜, battling back after work uniforms repress blade for 4×100㎜, 640㎏ gross weight was optimized. Optimization of field test the tractor speed shift 1(0.45㎧∼0.53㎧) and in the repression and crop height 40∼ 60㎜ uniforms, respectively. Appropriate working conditions identified by weight in the roller by type by speed test results, the weight is heavy, long repression and squeezed me, speed was increased, the lower the efficiency of repression.


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