• Journal of the Korean Society for Precision Engineering
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• v.22 no.2
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• pp.105-112
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• 2005

The guillotined cutting process for the pipe was studied in this paper. Until now guillotining mechanism can not be practically applied in the industries because of the deformation of sheared section around cutting area, the coarse sheared surface, and the burs. To find optimum shapes of blade, several types of blade were experimentally studied. The cutting force normal to the axial direction of the pipe was compared with the theoretical result based on the cutting energy. The experimental maximum cutting forces were very good agreement with the theoretical results. It also discussed that the design parameters of guillotining system such as the blade shape and the clearance between the blade and the die made effects to the deformation of the cutting cross section area. The results show that the guillotining method can be applicable to the pipe cutting system by optimizing the blade shape and the clearance between the blade and the die of the guillotined cutting system with respect to the sheared pipe material.

• Journal of Power System Engineering
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• v.11 no.3
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• pp.47-52
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• 2007

Punching, blanking, trimming and slitting are widely used in shearing processes in sheet metal forming of automotive parts. In this paper the effects of clearance, cutting angle and tool sharpness on the formation of burr were investigated by experimental method in shearing processes of steel sheets, SPCEN and SPRC35E. The amount of burr and the shapes of burr were different between two kinds of steel sheets. It has been shown that the cutting angle of the shearing blade had no effects on the height of burr when the clearance was below the 10% of the steel sheet thickness, and also that the height and shape of burr were not affected by the cutting angle when the wear of shearing blade was below the 10% of the steel sheet thickness. It was known that there had been existing the critical clearance of 10 to 15% for the tested steel sheet, SPCEN and SPRC35E.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2004.10a
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• pp.1440-1443
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• 2004

Shearing including punching, blanking, trimming, slitting, etc is one of the most frequently used processes in sheet metal manufacturing. It has been widely used for manufacturing autobody, electronic components, aircraftbody, etc. In this paper, it has been researched by the experiment to examine the effect of burr height corresponding to die clearance, cutting angle, tool sharpness, etc. This paper presents the experimental results with using Al alloy sheet.

• Korean Journal of Agricultural Science
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• v.11 no.2
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• pp.278-283
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• 1984

Shearing characteristics of cornstalks were investigated under quasi-static conditions at various knife approach angles and shear angles in order to determine their importance to the cutting action of mowers. Corn variety used in this study was pioneer that was grown in the field of Chungnam National University. The results obtained were as follows: 1. The shearing process had two shearing stages in cornstalks, which was different from those of rice and other forage crops due to the hard crust. 2. Force and energy of shear were decreased progresively with height of the cornstalks. 3. The minimum shear force occured at shear angle of about $60^{\circ}$ and approach angle of about $10^{\circ}$ 4. The condition of minimum shear energy coincides with that of minimum shear force. 5. Effects of knife approach angles were more significant than those of shear angle for force and energy of shear.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2004.10a
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• pp.19-22
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• 2004

Shearing including punching, blanking, trimming, slitting, etc is one of the most frequently used processes in sheet metal manufacturing. It has been widely using for manufacturing autobody, electronic components, aircraftbody, etc. In this paper, it has been researched by the experimental investigation to examine the influence of shearing processes parameters such as clearance, cutting angle, material properties, etc. From the results of experiment, it has shown that it gives the small variations at burr height below the proper clearance and it also presents that it is no affected the variations of cutting angle.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.6 no.2
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• pp.17-21
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• 2007

Shearing including punching, blanking, trimming, slitting, etc is one of the most frequently used processes in sheet metal manufacturing. It has been widely used for manufacturing autobody, electronic components, aircraftbody, etc. In this paper, it has been researched by the experiment to examine the effect of burr height corresponding to die clearance, cutting angle, tool sharpness, etc. This paper presents the experimental results with using Al alloy sheet.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 2002.02a
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• pp.3-8
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• 2002

본 연구는 트랙터 부착형 자동 토양경도 측정 시스템의 개발에 관한 연구로서, 우리나라 토양조건이나 작업형태에 맞는 에너지 절감형 트랙터 로타리날을 개발하기 위한 전단계 연구로서, 기존에 개발된 로타리날과 개량, 보완되어 개발될 로타리날의 성능을 비교 분석하기 위하여 수동 토양경도 측정기의 부정확성을 개량하여 측정의 정확성을 통한 동일 실험조건에서의 실험을 실시하고자 자동으로 작동되며 토양경도측정을 할 수 있는 트랙터 부착형 자동 토양경도 측정 시스템을 개발하는데 목적이 있으며, 그 구체적인 연구 결과는 다음과 같다. (1) 시스템은 토양경도 측정부, 측정장치 구동부, 그리고 트랙터와의 연결부로 구성되었다. (2) 시스템 작동에 필요한 전원공급을 트랙터 배터리에서 공급하였다. (3) 토양경도 측정시 토양속에 돌이나 이물질 층이 형성되어 있는 경우에 콘 페니트로메타가 관입하다가 큰 관입저항 때문에 관입저항 한계설정치까지 가기전 더이상 관입을 못하는 경우가 발생하였다. (5) 성능실험시 관입심이 깊을수록 시험포장 전체에서 대체적으로 토양경도가 높은 것으로 나타났으며, 토양속의 돌이나 이물질 등에의해 경도가 급격히 증가하는 부분이 있는 것으로 사료된다. 이상의 결과에서 살펴보면 본 시스템은 토양경도 측정에 적절하다고 사료된다.

• Journal of the Korean Geotechnical Society
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• v.36 no.9
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• pp.33-44
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• 2020

In order to analyze the shear strength characteristics of the grout with sudden gelation in the pre-hardening state, the viscosity of the mixture and the indoor vane shear test were performed. The grout was prepared according to the water-cement (w/c) ratio and the shear strength test was conducted. The plastic-state shear strength of grout was affected by the w/c ratio, so the lower the w/c ratio, the higher the initial shear strength was, and the longer the curing time was, the higher the shear strength was. The maximum shear strength occurred at the faster rotation angle as the higher shear strength was developed, and the lower shear strength occurred at the larger rotation angle. In addition, it was confirmed that the pre-hardening grout rapidly decreased in strength after the maximum shear strength was gained, and converged at a certain level after the rotation angle of the vane blade was about 70° to 90°.

• The Journal of Engineering Geology
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• v.23 no.4
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• pp.511-517
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• 2013

The Field Velocity Probe (FVP) has been widely applied to determine the various characteristics of soils. This study seeks to estimate soil consolidation characteristics using an FVP and to increase its application in the field. The specimens were extracted from depths of 3 and 6 m at the study site, an area of soft clay in Incheon. In laboratory testing, the specimens were placed in an improved oedometer cell to measure shear wave velocity, and statistical analysis was performed to compare the results of effective stress and shear wave velocity. FVP enables increased resolution in the field because it measures the shear wave velocity every 20 cm. To estimate the condition of consolidation, we compared the results of shear wave velocities between those obtained in the laboratory and those in the field. The field conditions are used to analyze overconsolidated and normally consolidated soils at depths of 3 and 6 m, respectively. The results show that FVP is a suitable method for estimating the degree of consolidation.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.36 no.3
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• pp.463-470
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• 2016

A vane shear test (VST) is a simple testing method for determining an undrained shear strength of cohesive soils by minimizing soil disturbance. In this study, the VST was used to determine a shear strength of sand. Dry Nakdong River sand was prepared for loose and dense conditions in a cell and then pressurized with 25, 50, 75 or 100 kPa from the surface of sand. A vane (5 cm in diameter and 10 cm in height) was rotated and a torque was measured within sand. When a torque moment by vane and friction resistance moment by sand is assumed to be equalized, a friction angle can be obtained. When a vane rotates within clay, a uniform undrained shear strength is assumed to be acting on cylindrical failure surface. On the other hand, when it is applied for sand, the failure shape can be assumed to be an octagonal or square column. The relationship between measured torque and resistant force along assumed failure shapes due to friction of sand was derived and the internal friction angle of sand was determined for loose and dense conditions. For the same soil condition, a series of direct shear test was carried out and compared with VST result. The friction angle from VST was between 24-42 degrees for loose sand and 33-53 degrees for dense sand. This is similar to those of direct shear tests.