• Proceedings of the Korean Society of Precision Engineering Conference
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• 2001.04a
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• pp.1000-1003
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• 2001

This paper presents the numerical analysis and experimental verification to know the metal cutting burr formation mechanism in face milling operation. Finite element method are applied to predict the 2-D burr formation process prediction. Face milling process are adjusted to analyze the characteristics of burr shapes according to various cutting conditions. The cutting parameters were investigated with cutting speed, feed rate, depth of cut. Through the experiments various burr types are classified according to its shape and properties.

• Journal of the Korean Society for Precision Engineering
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• v.19 no.3
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• pp.73-79
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• 2002

This paper presents the experimental results to verify the environmental consciousness with economic balances due to cutting fluid behaviors, effectiveness in machining process. Even though cutting fluid improves the Productivity through the cooling, lubricating effects, its environmental impact is also increased according to the cutting fluid usage. The primary mechanism considered in this study is the spin-off motion of fluids away from rotating workpiece. In this study some parameters arc adopted to analyze the productivity(tool wear), environmental impact(mist diffusion rate). The results present talc criteria for the resonable cutting fluid usage quantitative1y to develop the environmentally conscious machining process.

• Journal of the Korean Society for Precision Engineering
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• v.6 no.4
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• pp.71-83
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• 1989

The optimization in the machining process has been a long-standing goal of the manufacturing community. The optimization is composed of two main subjects;one is to select an optimum cutting condition, and the other is to detect the emergency situation and take necessary actions in real-time base. This paper proposes a reliable and practical guide system whose purpose is the optimization of cutting conditions, and the detection of tool failure in the machining process. The optimal cutting conditions are determined through the estimation of tool wear rate and the establishment of access- ible field from the measured cutting temperature and force. Tool breakage is detected by the normal force component acting on minor flank face extracted from on-line sensed feed force and radial force. In experiments, the proposed guide system has proved availability for the decision of reliable cutting conditions for the given tool-work system and the detection of tool breakage in ordinary cutting environments.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2000.05a
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• pp.948-951
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• 2000

This paper presents the analytical and experimental methodology for the prediction of aerosol concentration and size distribution due to cutting fluid atomization mechanism in turnining operation. The established analytical model which is based on atomization theory analyzes the cutting fluid motion and aerosol generation in machining process. The impinging and evaporation experiments were performed to know the particle size and evaporation rate of cutting fluid. The predictive models can be used as a basis for environmental impact analysis on the shop floor. It can be also facilitate the optimization of cutting fluid usage in achieving a balanced consideration of productivity and environmental consciousness.

• Journal of Korean Institute of Industrial Engineers
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• v.26 no.2
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• pp.165-170
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• 2000

In order to perform a successful material cutting process, the operators are to select the suitable machining tools and cutting conditions for the cutting environment. Up to now, this has been a complicated procedure done by the data in the tool manufacturers' paper catalog and the operator's experiencial knowledge, so called heuristics. This research is motivated by the fact that using computer techniques in processing vast amount of data and information, the operator can determine the tool and cutting condition easily. In the developed program, the selection of milling cutter, insert, and components are combined to provide optimal cutting speed, depth of cut, feed rate, rpm, and power. This program also provides the selection routine for end mill, drilling, turning, and grinding where the suitable tools are selected by workpiece, holder type, cut type, and insert shape.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.7 no.3
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• pp.14-21
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• 1998

The in-process detection of the state of cutting tool is one of the most important technical problem in Intelligent Machining System. This paper presents a method of detecting the state of cutting tool in turning process, by using Artificial Neural Network. In order to sense the state of cutting tool. the sensor fusion of an acoustic emission sensor and a force sensor is applied in this paper. It is shown that AErms and three directional dynamic mean cutting forces are sensitive to the tool wear. Therefore the six pattern features that is, the four sensory signal features and two cutting conditions are selected for the monitoring system with Artificial Neural Network. The proposed monitoring system shows a good recogniton rate for the different cutting conditions.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2002.10a
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• pp.147-152
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• 2002

The mechanism of the aerosol(mist) generation generally consists of spin-off, splash, and evaporation/condensation. Host researchers showed some theoretical model for predicting the particulate size and generation rate without real cutting in turning operation. These models were based on the spin-off mechanism, and verified good for modeling the process. However, in real machining, the cutting tool destroys the flow direction of the cutting fluid and generate the heat by the relative motion of between tool and workpicee, and so the mass loading of the mist is greatly increased as compared with non-cutting. In this paper, we show some experimental data that the mist formation characteristics of cutting is different from that of non-cutting.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.20 no.12
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• pp.3899-3908
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• 1996

In order to clarify the effects of nonmetallic inclusion contents insteels (SM45C & SCM440) on the tool life, cutting experiment was performed under various cutting conditions. Tool life, cutting force, roughness of machined surface and cutting mechanism are examined on these two kinds of steel. The following conclusions were obtained from the analysis (1) Cutting force of the steels was not affected by chemical component and nonmetallic inclusion. (2) If the rate of amount, Ca/S has a value grater than about 0.2 and addition of less amount of Al, Mn, tool wear of tips decreasesinturning. (3) It is also proved that higher contents of nonmetallic inclusion improve roughness of the surface. (4) Less amount of Ca, higher amount of S, Mn and Al improve the chip breakability.

• Journal of The Korean Society of Grassland and Forage Science
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• v.9 no.2
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• pp.68-76
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• 1989

The effect of characteristic of mixture sowing combination on the development of botanical composition was conducted for 12 years on the meadow experiment. The results of this study were summarized as follows. 1. Festuca pratensis lost the expected position of a dominant species. Its vegetation ratio decreased gradually until the last survey year. 2. Arrhenatherum elatius, known as a typical 2-cutting grasss, developed to a dominant species only in the 3- cutting plot without limitation. 3. Alopecurus pratensis, whose feeding value diminishes rapidly, developed to a dominant species regardless of N-fertilization under the condition of 3-cutting, even though the same small amount of seeding was introduced as usual. 4. Trisetum flavescens which causes calcinose exceeded the 40% of vegetation ratio which was the approved rate for feeding at the high N-level (2OOKgIha). 5. Among the introduced, the species showed the significance in quantity were Lotus corniculafus solely in the 2-cutting plot, and Trifolium repens solely in the 3-cutting plot. In the 3-cutting plot legume yet remained under N-fertilization. 6. The appropriate ratio of vegetation for the subordinate species in the mixture sowing combination was easily attained from the least amount of seeding (Gramineae with max. 3Kg/ha, Leguminosae with max. 2kgIha). 7. Into the mixture sowing combination, infiltrated unintroduced species marked more noticeably in the 2- cutting plot than in the 3-cutting plot.

• Journal of the Korean Society for Precision Engineering
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• v.2 no.2
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• pp.43-59
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• 1985

In relation to the machinability of drilling operation, experiments were made to investigate the effect of cutting condition on static as well as dynamic cutting resistances in cutting plane carbon steel (SM 45 C) with H.S.S. twist drills. The results were as follows. 1) The static cutting resistances on carbon steel can practically be calculated by the following equations which were derived from experimental result. The deviation from the experimental values was less than 8% and 13% for cutting torque and thrust respectively. For cutting torque M: M=0.019 $H_B\;{f^{0.68}d^{1.68}$ For thrust T: T=0.400406 $r^{0.6}d^{0.68}$ + 0.1835 $H_BC^2$(where $H_B$: Brinnel hardness) 2) The static components of cutting resistance are increased exponentially with increasing drill diameter and feed rate. On the effect of drill diameter, the dynamic components of torque are decreased with increasing dirll diameter because of rigidity, the dynamic components of thrust being not effected with the changes. 3) As feed rates increase, the dynamic components of torque rather decrease although its changes on thrust components are unstable. 4) The static components of cutting resistance and dynamic component of torque are slightly decreased in accordance with the increase of spindle speed although its dynamic thrust components are not effected by the spindle speed.