切削抵抗의 動的成分에 미치는 切削條件의 影響에 關한 硏究(Ⅱ)

全彦燦,남궁척 충남대학교 공업교육연구소 1986 論文集 Vol.8 No.3

In this study, the static and dynamic commponents of cutting resistance were measured with tool dynamometer (Swiss, piezo-electric type) when S 45 C, Al-alloy and brass were drilled under the some variable conditions. 1) The dynamic components of these cutting resistance are not related to the depth of drilled hole. 2) The static and dynamic components of cutting resistance are increased in accordance with the increase of feed and drill diameter. 3) The dynamic components of thrust force are increased in accordance with the increase of spindle speed. 4) The rate of the dynamic component to the static component is 0.3∼0.5 in torque, 0.1∼0.2 in thrust force. 5) The characteristic of the tool system is affected in dynamic component of cutting resistance, and the created frequency and amplitude of the chip are determined by the drilled materials. 6) The maximum amplitude of the dynamic component is increased proportionally in accordance with the feed rate and the spindle speed.

BAF 燒鈍의 傳熱特性과 冷延鋼板의 表面淸淨度에 관한 硏究

全彦燦,金舜經 동아대학교 공과대학 부설 한국자원개발연구소 1995 硏究報告 Vol.19 No.2

A cold spot temperature control system for the BAF(batch annealing furnace) has been established in order to reduce energy consumption to improve productivity and stabilize the properties of products. Therefore we confirmed for the improving of material quality (eq. even and consistent tempering, high surface cleanliness, reduced carbon depositing etc.), increasing of output, comparison of annealing cycle time, reducing of annealing cost and distribution of cold spot temperature according toe BAF type. The use of hydrogen instead of nitrogen as the protective gas, combined with high convection in batch annealing furnaces, has shown that considerable increases in furnace output and material quality are attainable. Owing to the low density, high diffusion and reducing character of hydrogen, a better transfer resulting in uniform material temperatures and improved coil surfaces can be achieved.

조질 압연용 작업롤의 조도가공에 관한 연구

전언찬,김순경 韓國工作機械學會 2000 한국생산제조학회지 Vol.9 No.4

X-Y 테이블에 사용되는 볼 스크류의 열팽창 억제에 관한 연구

전언찬,이승수,김민주,곽창식,장성규,한근조,김중완,박홍식,전태옥,박정보 동아대학교 공과대학부설 생산기술연구소 1997 生産技術硏究所硏究論文集 Vol.2 No.2

In this paper, we have studied about the thermal expansion of the ball screw used for the X-Y table. The hollow ball type is used for the vall screw. We have compared the conventional cooling system and function with the improved cooling system and function which is developed the path providing cooling oil in hollow ball screw. That is, the temperature variation and positioning accuracy are analyzed of the ball screw. We have obtained the following result through this experiment. 1) The improved cooling system of the hollow ball screw for X-Y table was developed. 2) The improved cooling system of the hollow ball screw has a large effectiveness on restraining the thermal expansion of the ball screw. 3) The positioning accuracy of the ball screw was improved about 2∼4㎛ using temperature-controlled colling oil.

자동 형상제어용 측정롤의 특성에 관한 연구

전언찬,김중완,김순경,김문경 동아대학교 공과대학부설 생산기술연구소 1996 生産技術硏究所硏究論文集 Vol.1 No.2

The continuing demand for quality products requires better understanding and improved control of the production process. And, in recent year requirements for flatness control in strip rolling have become increasingly severe because of the control for flatness of cold rolled strip is essential for further down stream processing. Also a speeds of rolling mills to meet productivity requirements puts a demanding requirement on the control of flatness of rolled strip. The demands on a total flatness control system therefore are a measuring and indication system consisting of a measuring roll that is robust, accurate, reliable and require a minimum of maintenance. The critical part of any control system is the quality of the information being provided by measurement instrument or device. It is therefore of utmost importance to have an accurate, repeatable measuring system.

HNx 분위기가스중에서 BAF소둔시 코일의 온도변화에 관한 연구

전언찬,김순경 대한기계학회 1994 대한기계학회논문집 Vol.18 No.5

A cold spot temperature control system for the batch annealing furnace has been established in order to reduce energy consumption which is essential to improve productivity and stabilize the properties of products. A relationship between annealing cycle time and gas flow rate is developed and also for the variation of coil cold spot temperature with time during heating, and actual temperature measurements at mid-width of each coil during soaking. The results of the temperature variation effect on the cold rolled steel sheet batch annealing are as follows. (1) Cooling rate increasing gradually with increasing atmospheric gas flow, but heating rate is hardly increasing without atmospheric gas component change. (2) In case of short time heating, the slowest heating part is the center of B coil and in case of ling time heating, the low temperature point moves from the center of coil to inside coil. (3) The outside of top coil is the highest temperature point under heating, which becomes the lowest temperature point under cooling. (4) Soaking time determination depends on the input coil width, and soaking time for quality homogenization of 1214 mm width coil must be 2 hours longer than that of 914 mm width coil.

냉간압연기의 유압압하식 자동 두께제어장치에 관한 연구

전언찬,김문경,김순경 동아대학교 공과대학부설 생산기술연구소 1996 生産技術硏究所硏究論文集 Vol.1 No.-

Recently, the necessity for more accurate automatic gauge control(AGC) has increase of customers' requirement for cold rolled steel sheets with thinner gauge and better gauge quality. Therefore, many cold rolling mills replaced its electric screw down automatic gauge control system with a new hydraulic automatic gauge control system, to ensure closer gauge tolerance. In this paper, the performance of a hydraulic automatic gauge control system for cold rolling has been investigated under industrial conditions. It was investigated that variation of gauge deviation according to the final products thickness, cold rolling speed and pass number, in the actual rolling mill. As a result, it was found that the system enalbes strip thickness variation to be reduced substantially and caused by poor gauge deviation have been drastically decreased. The test results are as following. The more the exit steel strip thickness is thick, the larger the gauge deviation rate is large, and the more it is thin, the large the gauge deviation rate is large. Because the gauge devuation is larger at acceleration speed and deceleration speed than steady speed, so automatic gauge control system is better to adopt over 50m/min, automatic gauge control system reduces rapidly large thickness deviation.

역설계 시스템 적용을 통한 프레스 성형물 검사

전언찬,김수용,김민주,이승수 대한기계학회 2004 大韓機械學會論文集A Vol.28 No.9

자동설계 모델을 이용한 최적설계 조건에 관한 연구

전언찬,김민주,이승수 東亞大學校 2001 東亞論叢 Vol.38 No.-

This study is an investigation for the ADS optimum design by using FEM. We write out program which express ADS perfectly and reduce the required time for correcting of model to the minimum in solution and manufacture result. We complete algorithm which can plan optimum forming of model by feedback error information in CAE. In rachet wheel, greatest equivalence stress originates in key groove corner and KS standard Is proved the design for security.

강판의 자동 형상제어 장치의 특성에 관한 연구

전언찬,김중완,김문경,김순경 동아대학교 공과대학부설 생산기술연구소 1996 生産技術硏究所硏究論文集 Vol.1 No.2

In this paper, the performance and functions of automatic flatness control system installed on the 4 hi-reversing mill and has been investigated under actual conditions. A new automatic flatness control system incorporates a measuring roll for measurement and correction calculations, hydraulic roll benders, selective roll cooling, and a programmable controller forinterface and data logging. The test results are as following. The more the exit steel strip thickness is thick, the smaller the I value, and the more it is thin, the larger the I value. And, a complex distribution of strip tension was controlled, for example, not only a quarter buckle but also a simple center wave and edge wave. Because the tension deviation is larger at acceleration speed and deceleration speed than steady speed. so automatic flatness control system of contact type is better to adopt over 450 m/min, automatic flatness control system reduces rapidly large flatness deviation. The maximum I value of strip has been decreased to 13 I, and defects caused by poor flatness have been drastcally decreased. And coolant temperature for work roll cooling system on the automatic flatness control system is better to adopt about 50-55℃.