BTA드릴에 의한 심공가공시 최적절삭조건과 공구수명에 관한 연구

장성규,이충일,전언찬,안찬우,김현수 동아대학교 공과대학부설 생산기술연구소 1996 生産技術硏究所硏究論文集 Vol.1 No.2

The BTA deep hole machining has an increasing because of its wide range applications and its good productivity. The BTA tools are capable fo machining for having a large length to diameter ratio in single pass. It's really necessary that the research for machining of the deep hole drilling by the BTA drilling because its required quality should be satisfied with one time machining. In machining deep holes by single edge BTA drill, P10 class of tool material out of single tube BTA drilling system, we got the result of our study of selecting the optimum cutting condition and tool life for an object, SM55C through our testing as follows. (1) Cutting speed V=42m/min, and feed speed F=90mm/min is the optimum cutting condition and the tool life was about 10 meters. (2) The testing was shown surface roughness was 12㎛, and the roundness was less 16㎛.

부모 ·자녀관계 연구의 최근 동향 : Family Systems Approach

박성연 新羅大學校 1987 論文集 Vol.24 No.-

This purpose of this article is to document the current trend in the studies of parentchild interactions. The current transition toward a multidisciplinary approach to social science leads to consideration of dynamic reciprocities in family-child interaction. Social sciencetists increasingly recognized that happens on one level of anaysis depends largely on what happens on all others. The dynamics of this focus involves the contributions of the individual to the familial context. Simultaneously, the view focuses on the contribution of the familial context to the individual`s life span development. In addition, the interests of human developmentalists and of family socialists are merging. That is, they begin to see the family as a system. Most studies of family as a context of human development have concentrated on intrafamilial processes of parent-child interaction. For future investigation, extrafamilial processes which influencing intra familial processes should also be explored. In regard to method, proce-dures will have to be established to record reciprocal interchanges among all possible levels of analysis. New statistical techneques should be developed to analyze continuous reciprocity.

기름의 水面被膜에 따른 再曝氣係數의 變化

閔盛基,孫晋彦 동아대학교 환경문제연구소 1979 硏究報告 Vol.3 No.1

본 연구는 기름의 오염이 해양 및 하천에 미치는 영향을 검토함에 있어서 그 기초자료 내지 공업적 적용 방법을 알아보는데 있으며 대기에서 재폭기 계수의 변화를 측정, 고찰하는데 있다. 기름은 A-중유를 사용하였으며 수온은 5∼35℃까지 비교적 넓은 온도분포에 대해 실험적으로 검토하였다. 본 실험에 있어서는 유막이 존재할 때 재폭기 계수 k₂는 20∼40% 저하하고 온도계수 θ는 1,040으로 상승하여 DO평형농도는 최고 11%정도 증가함을 알았다. The purposes of this research are to find out the basic data for the examination of the effects of oil pollution upon the reaeration phenomena in seas and rivers, and the industrial application of the data, to measure and study the changing of reaeration rate of oil-covered pure water. Experiments were carried out with bunker-Atype petroleum as a covering material and at comparatively wide-ranging temperatures(5∼35℃). In the experiments, the changing of the reaeration coefficient k₂, and the temperature coefficient as well as that of the equilibrium concentration of dissolved oxygen in case of oil slicks were examined.

초경 드릴의 절삭 성능에 관한 실험적 평가 연구

장성규,변상기,이승수,김현수,전언찬 동아대학교 공과대학부설 생산기술연구소 1997 生産技術硏究所硏究論文集 Vol.2 No.1

Among the cutting process, recently hole processing in one of extensive using. This study, we made use of the 3 point edge drill. Regarding the cutting efficiency, we investigated the shape of cutting hole and studied cutting hole, a slope of center shaft, roundness and surface roughness. By using carbide 3 point cutting edge, compare with 2 cutting edge, it is possible that high precision drill processing and near the hole, at extremely limited area, quantity of magnification is a little big. After 15m cutting distance, a gradient of center shaft values was fixed 22㎛. It is necessary that a sufficient consideration concerned with jig intensity of workpiece, cutting conditions etc.

자동차용 ABS MKⅣ-G의 성능 평가에 관한 연구

장성규,전언찬,김대원 동아대학교 공과대학부설 생산기술연구소 1997 生産技術硏究所硏究論文集 Vol.2 No.2

High performance ABS have been introduced in the market because car manufacturers and drives have been recongnized the important safety function of these systems. In the beginning of ABS introduction only luxury vehicles where equipped with ABS because of the high additional cost. Today there is the medium and even compact vehicle class. Therefore it became a necessity to develop an ABS which meets the requirements of manufacturers and drivers concerning performance comfort and especially cost. As a highly advanced technology and skills which include electronic, hydraulic controls, element design and manufacturing technology. ABS system has recently been entered into mass production as a result of long research and many try and errors. In this research, we tested MKⅣ-G ABS system, which was developed by ITT automotive, in various methods and got the quite good results in its function. MKⅣ-G ABS system can be extended to TCS(Traction Control System) function and is now under developing by localization in domestic. But on demand car manufactures and customers, new generation ABS system, that means simple, low cost and high function, is already under developing among advanced nations in this area. Although we are still in early stage of ABS system development, if we analyze and study the function of various ABS system through these research and put it to practical use step by step, we can develop independent ABS model in the near future.

Caliper 조립 Line의 자동화에 관한 연구

장성규,전언찬,박흥식 동아대학교 공과대학 부설 한국자원개발연구소 1995 硏究報告 Vol.19 No.2

In order to improve productivity, we have developed dedicated multi-product and wide variety of products lines suitable for respective automobile models. However, because of a sagging market, in recent years, the productivity of dedicated manufacturing lines has declined remarkably. We have developed a high speed and high-effciency flexible manufacturing line to maintain high productivity in spite of production volume fluctuations and frequent engineering changes. This development has been applied to an assembly line of the caliper.

65세 이상의 노인 환자에서의 심판막 폐쇄부전증에 대한 임상적 고찰

류주성,왕준호,문언수,이홍순 대한노인병학회 2001 대한노인병학회지 Vol.5 No.4

BTA드릴에 의한 심공가공에서 구멍의 정밀도 향상에 관한 연구

장성규,전언찬 동아대학교 생산기술연구소 2000 生産技術硏究所硏究論文集 Vol.5 No.1

When the deep hole drilling with BTA drill, there are serious problems such as accuracy of diameter (deflection, hole over size), surface roughness to inhibit the required qualities. With the purpose of the accuracy improvement in deep hole drilling, we investigated the influence of the drilled hole accuracy and the cutting resistance of materials that occurred as the variation of the cutting condition after deep hole drilling with BTA drill on SM55C. And we obtained the following results. 1) The burnishing torque is closed upon 26% of the cutting torque in a single edge BTA drill or multi-edge BTA drill. The multi-edge BTA drill is better dispersed the cutting torque than the single edge BTA drill. 2) In hole over size, the drilling accuracy according to the drilled length is best improved under the condition of V=70m/min, f=0.15mm/rev in the multi-edge BTA drill. Values of hole over size are then about 25μm on 0∼0.5m, about 0μm on 10∼20m, and about-l5μm on over 20 m. 3) The surface roughness is distributed 9.1∼10.9 μm in the single edge BTA drill and 3.28∼6.3 μm in the multi-edge BTA drill. And the surface roughness is irrelated to the cutting speed.

BTA 드릴링에 있어서 모터 전류를 이용한 절삭이상상태 감시에 관한 연구

장성규,장성화,전언찬 동아대학교 공과대학부설 생산기술연구소 1998 生産技術硏究所硏究論文集 Vol.3 No.2

In the tube-seat working of heat exchanger using BTA drilling among the deep hole drilling process, this paper analyses the property about the tool breakage monitoring in the deep hole drilling as detect the current signal of main spindle motor and analyse the change of cutting force through the experiment for the workability measurement in the low-carbon steel and stainless. We obtain the following conclusions through this experiments. 1) We could detect the current of AC spindle motor through the indirect measuring system of cutting force without using the tool dynamometer. 2) We could observe the change of cutting force and tool breakage monitoring by detecting only the main spindle motor current in the deep hole drilling machine. 3) We could sufficiently observe tool breakage monitoring with detecting the main spindle motor current in BTA drilling process of deep hole drilling machine. 4) We could observe that the limit value approaches 20kg-cm in the 0.4mm range of flank wear.

싱글 튜브 시스템 BTA 工具를 使用한 SM55C 鋼의 深孔 加工 特性에 관한 硏究

全泰玉,全彦燦,沈成輔,張性圭 동아대학교 공과대학 부설 한국자원개발연구소 1994 硏究報告 Vol.18 No.2

The BTA deep hole machining has an increasing demand because of its wide applications and its good productivity. The main feature of the BTA drill is that the tool cutting edges are unsymmetrically located on the boring head. This provides a stabilizing cutting force resultant necessary for self guidance of the boring head. The BTA drills are capable of machining for having large length to diameter ratio in single pass. The study of the accuracy and surface finish of holes produced would reveal quite useful information regarding the process. This thesis deals with the experimental results obtained during single tube system BTA machining on SM55C steel for different machining conditions.