• 제목/요약/키워드: Saw-cutting

검색결과 93건 처리시간 0.035초

레이저변수(變數)와 피삭재조건(被削材條件)이 목재(木材) 및 목질(木質)보드의 절삭특성(切削特性)에 미치는 영향(影響)(II) - 비절삭(比切削)에너지와 절삭면(切削面)의 품질(品質) - (Effects of Laser Parameters and Workpiece Conditions on Cutting Characteristics of Solid Wood and Wood-based Panel(II) - Specific Cutting Energy and Surface Qualities -)

  • 심재현;정희석
    • Journal of the Korean Wood Science and Technology
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    • 제26권1호
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    • pp.38-50
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    • 1998
  • Laser cutting tests were conducted to investigate the laser cutting characteristics of solid woods such as 25mm-thick white oak(Quercus acutissima) and maple(Acer mono), and wood-based panels such as 15mm-thick medium density fiberboard and particleboard. Test variables were laser power, cutting speed, grain direction, and moisture content. Specific cutting energy was measured and the qualities of cut surface were estimated in constant laser power. Specific cutting energy of white oak was larger than that of maple, and specific cutting energy of medium density fiberboard was smaller than that of particleboard. For both white oak and maple, specific cutting energy of green wood was smaller than that of air-dried wood because weight loss of moisture evaporation in green wood was larger than that in air-dried wood. In laser-cut surface, wood cells were not deformed and damaged, but in circular saw-cut surface fibers were pushed out and cut, and wood cells were deformed severely. However, mechanical surface roughness of saw-cut surface was smoother than that of laser-cut surface because of the existence of undeformed cell cavity in laser-cut surface.

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고속 회전 톱의 불안정 현상에 대한 진단 (Diagnosis on Unstable Phenomenon of High-Speed Rotating Circular Saws)

  • 임경화
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 1998년도 춘계학술대회논문집; 용평리조트 타워콘도, 21-22 May 1998
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    • pp.187-193
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    • 1998
  • In the tandom pencil slat saw lines, feeding of cedar blocks is often stopped because excessive motor current is required in a saw machine. These events are called "kickoffs' in factory lines. Kickoffs decrease productivity due to machine down-time and damage to saw blades often accompanies them. Researches on saw behavior at kickoff are required to understand and reduce the frequency and severity of kickoff events. This research aims at understanding the fundamental mechanisms of kickoffs during cutting, predicting the impending kickoff and evolving design improvements for high cutting performance with fewer and less severe kickoffs.offs.

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산업용 고속절단기의 기동 시 충격완화에 대한 연구 (A Study on Vibration Reduction of an Industrial Chop saw in operation)

  • 김두환;임형빈;정진태
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2008년도 추계학술대회A
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    • pp.955-960
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    • 2008
  • In this paper, an impulse of an industrial chop Saw is identified by experimental method and the impulse is reduced by structural modification. For the impulse identification, vibration signals are measured by an accelerometer when the chop saw is operating. From some experiments, it is found that the impulse occurs when there is slip between spindle and the wheelwasher and contact area is small between the wheelwasher and cutting discs. The design of the wheelwasher for optimization is performed by the FEM and experiments and the prototype is manufactured. It is verified that considerable amount of impulses are reduced by the structural modification.

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하드디스크 드라이브용 액츄에이터 암의 절삭 가공 특성 (Cutting Characteristics of Actuator Arm in Hard Disk Drive)

  • 이재우
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 2006년도 춘계학술대회 논문집
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    • pp.11-12
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    • 2006
  • Actuator arm of HDD were machined with the slitting saw of tungsten carbide to clarify the cutting characteristics in terms of the roughness of machined surface, the burr size and the tool wear. An improved performance in all view of the surface machined, the tool life and the cutting efficiency was obtained at the cutting speed of 4,000rpm with the feed of 300m/min. The tool life increases with increasing the t/T value, whereas surface roughness decreases. The tool with alternate type of B and C edges has an effect to decrease the burr size.

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티타늄의 절삭성에 관한 연구 (A Study on the Machinabilty of Tianium)

  • 홍환표;오석형;서남섭
    • 한국정밀공학회지
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    • 제6권1호
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    • pp.45-51
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    • 1989
  • In metal cutting various types of chips are produced in consequence of cutting conditions. According to the type of chips the cutting mechanism is to be changed. Most of the cutting theory is based on the continuous chip because of its convenient analysis, but the occurrence of the saw-toothed chip depends upon the workpiece and/or the cutting conditions, one of which is titanium alloy used widely. Nowadays titanium alloys are used widely with the rapid development of aerospace structural engineering application, whereas the theory of cutting mechanism has not been established yet, and the formatting process has not been understood satisfactorily, either. Unfortunately several misconceptions, conflicting statements and statements needing further clarifi- cation are also found. In this paper an attempt is made to clarify the formation process of saw-toothed chips which are to be produced during the orthogonal cutting process of titanium alloys. They were machined at low speed to avoid the rapid tool wear. We observed the SEM-photographs of chips taken at the quick-st- opping device. It is hoped that a rational model of the mechanics of cyclic chip formation can be developed. The results obtained are as follows. 1. When a saw- toothed chip is formed, the shear band begins at the primary shear zone and trans- fers to the free surface, so that a segment is produced and it is completed by upsetting between the formatting segment and the formatted segment. 2. As the rake angle or the clearance angle increases in the machining of the titanium alloy, the chip approaches to that of the continous type. 3. When the rake angle and the clearance angle are increased the shear energy and the unit friction energy decrease, which shows the same aspect as that of the continuous chip.

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구성인선을 고려한 소형 박판 밀링공구의 설계 (Design of A Small Thin Milling Cutter Considering Built-up Edge)

  • 정경득;고태조;김희술
    • 한국정밀공학회지
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    • 제18권5호
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    • pp.130-136
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    • 2001
  • Generally, a metal slitting saw is plain milling cutter with thickness less than 3/16 inch. This is used for cutting a workpiece that high dimensional accuracy and surface finish is necessary. A small thin milling cutter like a metal slitting saw is useful for machining a narrow groove. In this case, built up edge(BUE) is severe at each tooth and affects the surface integrity of the machined surface and tool wear. It is well known that tool geometry and cutting conditions are decisive factors to remove BUE. In this paper, we optimized the geometry of the milling cutter and selected cutting conditions to remove BUE by the experimental investigation. The experiment was planned with Taguchi method based on the orthogonal array of design factors such as coating, rake angle, number of tooth, cutting speed, feed rate. Response table was obtained from the number of built-up edge generated at tooth. The optimized tool geometry and cutting conditions could be determined through response table. In addition, the relative effect of factors was identified bh the analysis of variance (ANOVA). Finally, coating and cutting speed turned out important factors for BUE.

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Effect of Spacing between Layers and Shape of Segment on the Performance of Pattern Saw Blade

  • Park, Hee-Dong;Kim, Youn-Chul;Chang, Joon-Ho;Shin, Min-Hyo
    • 한국분말야금학회:학술대회논문집
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    • 한국분말야금학회 2006년도 Extended Abstracts of 2006 POWDER METALLURGY World Congress Part2
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    • pp.1140-1141
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    • 2006
  • Diamond tools with several layers of diamond grits through thickness direction were tested by sawing. The saw blades with evenly distributed grits showed better cutting performance compared to the random distributed saw. At a given concentration of grits, as the spacing between layers was increased, the cutting performance was improved, and as decreased, it showed more tool life

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와이어쏘 공정에서 다이아몬드 입자의 인성지수가 절단 성능에 미치는 영향 (Effect of Toughness Index of Diamond Abrasives on Cutting Performance in Wire Sawing Process)

  • 김도연;이태경;김형재
    • 한국산업융합학회 논문집
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    • 제23권4_2호
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    • pp.675-682
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    • 2020
  • Multi-wire sawing is the prominent technology employed to cut hard material ingots into wafers. This paper aimed to research the effect of diamond toughness index on the cutting performance of electroplated diamond wire. Three different toughness index of diamond abrasives were used to manufacture electroplated diamond wires. The cutting performance of electroplated diamond wire is verified through experiments, in which sapphire ingot are cut using single wire sawing machine. A single wire saw for constant load slicing is developed for the cutting performance evaluation of electroplated diamond wire. Choosing the cutting depth, total cutting depth, cutting force and wear of electroplated diamond wires as evaluation parameters, the performance of electroplated diamond wire is evaluated. The results of this study showed that there was a significant direct relationship between the toughness index of diamond abrasives and the cutting performance. Results demonstrated that diamond abrasive with a high toughness index showed higher cutting performance. However, all diamond abrasives showed similar cutting performance under low load conditions. The results of this paper are useful for the development of cutting large diameter ingots and cutting high hardness ingots at high speed.