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.

MACHINING CENTER를 利用한 鏡面加工에서 表面粗度에 관한 硏究

최재용,전언찬 東亞大學校 海洋資源硏究所 1993 硏究論文集 Vol.6 No.1

This study has been performed to experiment of plastic metallic mold KP-4M on the variation of spindle revolution, feedrate, polishing times, grain size, and the pressure adding to tool.The results obtained from this study are as follows : 1. Surface roughness(Ra) grows worse, as the velocity is lower in the area of low revolution, and the velocity highter in the area of high revolution. 2. Above 1500rpm at the spindle revolution, Ra grows worse if polishing times (N) is less than 2 because of the preceding process, and the surface turn brillant if polishing times more than 4 because of loading. 3. As the higher pressure which adding to a tool is better when we expect more manufacturing quantity, and we need low pressure when surface roughness take precedence of quantity. 4. On the basic of the experimental findings, it is possible to be automatic of mirror like finishing with the machining center.

조질 압연용 작업롤의 조도가공에 관한 연구

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

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.

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.

Compensation(보정), Positioning accuracy(위치 정밀도)

홍성오,홍순남,조규재,전언찬 東亞大學校 1997 東亞論叢 Vol.34 No.-

Thermal expension of the ball screw in semi-closed loop type CNC lathe directly introduced positioning errors along the travel axis In this paper the thermal displacement of the ball screw is estimated by using macro variables. The estimated displacementes of the ball screw are given to the NC in the form of pitch error compensation data into time interval.The thermal behaviour of the ball screw of the CNC lathe under the constant driving conditions was measured to examine the effectiveness of this compensation method. The results showed that thermal displacements of the ball screw were the positioning accuracy could be maintained to better than 6μm which using this compensation.

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.

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.

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.

자동차 바디용 강판의 열처리 특성에 관한 연구

김순경,김문경,전언찬 東亞大學校 1998 東亞論叢 Vol.35 No.-

As demand for various kinds and small lot products has been increasing, batch annealing has been appreciated for its small restriction for the operation. The cold spot of the coil is very important in the BAF(Batch annealing furnace) annealing process. Because of the annealing cycle time in the BAF, annealing was decided on the cold spot of the coil Development on the mechanical properties of steel sheet for the automobile body panel is very important in the BAF annealing process. Because of the heat treatment method in the BAF, mechanical properties was decided on the heat treatment method of the coil. So, we tested on the development of mechanical properties according to heat treatment method at the annealing furnace using the Ax atmospheric gas and the HNx atmospheric gas. As a result of several investigations. We confirmed the following characteristics mechanical properties was changed under the influence of the annealing cycle and the atmospheric gas. The cold spot of coil was the mid point of the B coil in the Ax atmospheric gas. And, atmospheric gas is very important in the high convection annealing furnaces. And so, we tested the effect, variation of cold spot, for hydrogen contents of atmosphric gas at the annealing furnace. As a result of several investigations. We confirmed the following characteristics after the heating and soaking, the cold spot of coil moved to 1/3 of coil thickness in the HNx atmospheric gas, but the mid point of the coil thickness is the cold spot in the Ax or H2 atmospheric gas. Therefore, the use of hydrogen instead of nitrogen as the protective gas, combined with high convection in batch annealing furnaces, has shown that considerable increases n furnace output and material quality are attaninable. 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.