• Title/Summary/Keyword: Drill diameter

검색결과 125건 처리시간 0.039초

초경 Step Drill의 절삭성에 관한 연구 (A Study on the Cutting Performance of the Carbide Step drill)

  • 변상기;장성규;전언찬
    • 한국정밀공학회:학술대회논문집
    • /
    • 한국정밀공학회 1997년도 춘계학술대회 논문집
    • /
    • pp.1063-1067
    • /
    • 1997
  • A study of carbide step drill cutting ability is highly progessing the step drill with more then twice diameter rate is so difficult in regrinding and very easy to damage during machining. As the machining of step drill for closed hole is occur to breakage at small diamter poistion, so it is very difficult to machinine. Thue, in this experiment, We investance roundness and surface roghness by machining distance and were identifid that the first distance, 5~10m, was fine with 7 .mu.m but the arround of 15m was happened so much alternation. And we were indentified that after 20m was happend statable machining. The surface roughness was happened the same conditions. So application of stwp drill we think that the selection of cutting conditions need lots consideration and the study of step drill's diameter ratio ratio is carred out.

  • PDF

CFRP복합재료의 적층수와 드릴직경에 관한 연구 (On the Machinability of CFRP Composites Dependent on the Number of Stacking and Drill Diameter)

  • 정성택;박종남;조규재
    • 한국공작기계학회논문집
    • /
    • 제12권6호
    • /
    • pp.8-13
    • /
    • 2003
  • CFRP composite has a lot of merits such as mechanical characteristic, light weight and thermal resistance. For these merits CFRP is applied to so many industrial area. In order for the composite materials to be used in the aircraft structures or machine elements, accurate surfaces for bearing mounting or joints must be provided, which require precise machining. In this paper, the relationship between the stack thickness and drill diameter is examined from the drilling experiment, which is the drilling of 16, 32, 48p1ies specimen with the ${\phi}8$, ${\phi}10$, ${\phi}12mm$ cemented carbide drill. The results are analyzed with consideration of cutting force, stack thickness and drill diameter.

CFRP복합재료의 적층수와 드릴직경에 따른 가공 특성 (Drilling Characteristic of CFRP Composites depend on the number of stacking and drill diameter)

  • 정성택;박종남;조규재
    • 한국공작기계학회:학술대회논문집
    • /
    • 한국공작기계학회 2003년도 춘계학술대회 논문집
    • /
    • pp.190-195
    • /
    • 2003
  • CFRP composite has a lot of merits such as mechanical characteristic, light weight, and thermal resistance. For these merits CFRP is applied to so many industrial area. In this paper, the relationship between the stack thickness and drill diameter is examined from the drilling experiment, which is the drilling of 16, 32, 48 plies specimen with the $\phi$8, $\phi$10, $\phi$12mm cemented carbide drill. The results are analyzed with consideration of cutting force, stack thickness and drill diameter.

  • PDF

후판의 Drill가공에 있어서 Burr의 생성에 관한 연구 (Study on the Burr Formation in Drilling a Thick Plate)

  • 최성규;양균의;김태영;서남섭
    • 한국정밀공학회지
    • /
    • 제3권3호
    • /
    • pp.30-39
    • /
    • 1986
  • The burr worsens the accuracy of a workpiece and decreases a lot of pro- ductivity because it takes so much time and efforts to remove it. In this paper, the height, thickness and size of a drilling burr were derived from the drilling variables of drill diameter, chisel edge angle, web rate =($\Frac{2{\times}\;web\;thickness}{drill\;dia}$) and yielding stress of the workpiece as wel as feed, point angle and helix angle. The theoretical and experimental values of drilling thrust, torque and burr size of the testpiece were analyzed with the method of numerical analysis in a standard drilling condition. The order of choosing the drilling variables for the purpose of controlling the burr size was dealt in this paper with burr forming ratio. The results are as follows: (1) The drill diameter forms 42 percents feed 25 percents point angle 23 percents and web rate, chisel edge angle and gelix angle 5 percents of the partial differential slope of drilling thrust within the usual available ranges of drilling variables. (2) The drill diameter forms 55 percents feed 26 percents web rate 9 percents and chisel edge angle, point angle and helix angle 10 percents of the par- tial differential slope of drilling torque in the usual available ranges of drilling variables. (3) About 70 percents of the burr size can be controlled by feed, 29 percents by web rate in the case of a fixed diameter. It is recommended drilling10 variables to be chosen in the order of feed, web rate, drill diameter, point angle, chisel edge angle and helix angle so as to control the burr size effectively.

  • PDF

스테인레스 강의 미세구멍 드릴링 기술 연구 (A Study on the Micro Hole Drilling of Stainless Steel)

  • 김형국;연규현;송성종
    • 대한기계학회:학술대회논문집
    • /
    • 대한기계학회 2007년도 춘계학술대회A
    • /
    • pp.1517-1521
    • /
    • 2007
  • On this study, technical aspects were reviewed to drill a series of micro holes (${\phi}$0.10) over 200 within a few micron tolerance in diameter and position on the stainless steel material. Dedicated tools & jigs were designed and manufactured and optimum cutting conditions were found. On this micro hole drilling process, guide drill and step feeding were applied to help chip discharge, prevent drill breakage and finally improve the accuracy of positioning and roundness. The processing results indicated that most holes are distributed within a few micron tolerance in diameter and position intervals.

  • PDF

마이크로 드릴비트의 워터젯 세척 로봇시스템의 공정 시뮬레이션 분석에 관한 연구 (A Study on Process Simulation Analysis of the Water Jet Cleaning Robot System for Micro Drill-bits)

  • 국연호;박상록;박기진;최현진
    • 한국CDE학회논문집
    • /
    • 제20권3호
    • /
    • pp.291-297
    • /
    • 2015
  • A water jet cleaning robot system for micro drill bits is to refurbish micro drill bits used for the PCB manufacturing process. It can refurbish drill bits with the minimum diameter of ${\phi}0.15{\sim}0.075mm$ of which the total quantity have been discarded before. Micro drill bits with the minimum diameter of ${\phi}0.075mm$ can be cleaned by applying the water jet cleaning robot system out of the manual ultrasonic cleaning in the past for the cleaning equipment as the initial process in refurbishing. This study analyzed problems, while applying the apparatus mechanism for the workability such as the robot traces of Transfer Robot I and II, drill bit loading and unloading, and cleaning tasks in the water jet cleaning robot system in an effort to carry out simulations. In addition, the cleaning work process was optimized as the work process was verified in advance and the production quantity was analyzed through simulations.

Drill가공시 Drill과 가공구명내벽과의 마찰이 절삭저항성분에 미치는 영향 (A Study on the Effect of the Components of Cutting Resistance upon Friction between Drill and Inside Wall of Drilled Hole in Drilling)

  • 구연욱
    • 한국정밀공학회지
    • /
    • 제2권3호
    • /
    • pp.28-40
    • /
    • 1985
  • In this study, to check up on the effect of the components of cutting resistance upon friction between drill and inside wall of hole in drilling, the experiment was performed with individual specimen of carbon steel, cast iron, aluminium alloy under various cutting conditions: depth of hole, cutting speed, feed rate, shape and material of specimen. On the basis of the experimental results, the following conclusions are drawn; 1. The components of cutting resis- tance were increased in proportion to the increase of depth of hole owing to frictional resistance of drill margin and chip-jamming. 2. As feed rates increase, torque and thrust were increased. When comparing to the increasing rate for these components respecitively, thrust is higher tendency than torque. 3. As drill diameter increase, torque and thrust were increased. When comparing to the increasing rate for these components respectively, torque is higher tendency than thrust. 4. In the case of torque, the frictional resistance between drill margin and inside wall of drilled hole accounts for about 20 percent of carbon steel, 14 of cast iron, 10 aluminium alloy in drilling. But the effect of thrust force could be negligible. 5. Comparison between the theoretical and experimental results showed a close agreement so far as depth of hole is about three times of drill diameter. But there was a wide difference between them beyond the rane of three times, because of characteristics of the drilling process.

  • PDF

버형성 최소화를 위한 스텝드릴 개발 (Development of Step Drill Geometry for Burr Minimization)

  • 장재은;고성림
    • 한국정밀공학회지
    • /
    • 제19권11호
    • /
    • pp.183-191
    • /
    • 2002
  • Drilling tests were carried out using drills with various drill shapes for burr minimization. Final objective of this study is to develop compatible drill shape for minimization of burr formation. For experiments, general carbide drills, round drills, chamfered drills and step drills are designed and manufactured. Burrs are formed by various cutting conditions and in 4 different work materials. Laser sensor is used to measure burr geometries. Cutting forces in drilling are also measured and compared in every drill. As a result of the experiments, step drills with specific step angle and step diameter are suggested for burr minimization.

미소직경의 Single Edge형 드릴을 사용한 심공드릴링 공정의 가공특성에 관한 연구 (A Study on the Characteristics of Deep Hole Drilling Process Using Single Edge Drill with Small Diameters)

  • 최성주;이우영;박원규
    • 한국공작기계학회논문집
    • /
    • 제13권2호
    • /
    • pp.1-8
    • /
    • 2004
  • Applications of the deep hole drilling process can be found in many industries ranging from large aerospace manufacturer to small tool and die shop. Deep hole drilling process with small diameter generally requires high quality and accuracy. But problems which may arise or result from the deep hole drilling process include drill breakage, the generation of a finished part surface which does not satisfy required quality, and process instability. To guaranty the required machining quality and accuracy, it is important to understand and improve the deep hole drilling process. In this study, deep hole drilling experiments using tingle edge drill with small diameter under 2mm have been carried out for difficult to cut materials such as C42CrMo4 and C45pb and the experimental results were analyzed. Feed force and torque versus feed showed linear relationship in both materials. The feed force and torque are decreased as cutting speed is increased but the trends are not uniform in C42CrMo4.

드릴비트 직경에 따른 비틀림 제어 확장 앵커의 인발성능 평가 (Evaluation of Pull-out Performance of Torsion Control Expansion Anchor According to Drill Bit Diameter)

  • 채경훈;박태원;허무원;안영승;한주연
    • 한국구조물진단유지관리공학회 논문집
    • /
    • 제27권1호
    • /
    • pp.64-70
    • /
    • 2023
  • 본 연구에서는 1.04배 드릴비트 직경 및 1.02배 드릴비트 직경 시 앵커의 신뢰성시험을 수행하였다. 각 변수별 시험을 통해 앵커의 표준편차 및 변동계수를 검토하였고, 기준시험 결과와 비교 평가하였다. 1.04배 드릴비트 직경을 가진 M12 및 M16 앵커의 신뢰성시험결과, 극한 인장하중 허용기준 변동계수 값인 20% 이내의 값을 나타내어 시험기준을 만족하였다. 또한, 1.04배 드릴비트 직경을 가진 앵커의 성능은 기준시험 대비 M12 앵커는 약 74%, M16 앵커는 약 55% 정도로 나타나 앵커의 내력이 다소 부족한 성능을 나타냈지만, 설계강도 대비 약 253% 및 210%로 나타나 1.04배 드릴비트 직경에 설치된 앵커의 인발성능은 충분히 확보하고 있음을 알 수 있었다. 1.02배 드릴비트 직경을 가진 M12 및 M16 앵커의 신뢰성시험결과, 극한인장하중 허용기준 변동계수 값인 20% 이내의 값을 나타내어 시험기준을 만족하였다. 또한, 1.02배 드릴비트 직경을 가진 앵커의 성능은 기준시험 대비 M12 앵커는 약 48%, M16 앵커는 약 53% 정도로 나타나 다소 부족한 성능을 나타냈지만, 설계강도 대비 약 136% 및 168% 로 나타나 1.02배 드릴비트 직경에 설치된 앵커의 인발성능은 충분히 확보하고 있음을 알 수 있었다.