• Journal of the Korean Society of Manufacturing Process Engineers
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• v.2 no.2
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• pp.37-44
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• 2003

Composite materials are widely used to make all kinds of machine parts, internal and structural materials of cars, aerospace industries, building structures, ship materials, sporting goods and others. It is worth the while to use composite materials as various substitutions when compared With others. But the use is limited in the field of the mechanical processing because of its difficulties in cutting. The surface roughness of in and out in the hole processing was discussed after cutting the GFRP with HSS drill in the vertical machining center. And it is observed that as it processed more, the powdered chip may be got more than the fluid type long chip.

• International Journal of Precision Engineering and Manufacturing
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• v.8 no.1
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• pp.11-15
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• 2007

Composite materials are widely used to make all kinds of machine parts, internal and structural materials of cars, aerospace components, building structures, ship materials, sporting goods and others, It is worth while to use composite space substitute material in various applications when compared with others. But the use of composite material is limited in the field of the mechanical processing because of the difficulties in processing. Thus, it is proved that the surface is rough at the in and out sections of the hole processing when the GFRP is machined with HSS drill in the vertical machining center. And it is observed that the more it is processed, the more the fluid type long chip is changed into the powdered chip.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.3 no.4
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• pp.29-36
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• 2004

An experimental study on drilling of stainless steel is conducted using TiAlN coated drills and HSS twist drills with several cutting conditions; feed rate, spindle rotational speed, and dry/wet cutting. The effects of number of hole on the thrust force are examined by cutting force measurement. The flank wear of the drills and the change of hole diameter are quantitatively observed using a vision system. It is found that the thrust force in drilling with TiAlN coated drills decrease under dry and wet machining, whereas the flank wear resistance is improved.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 1999.10a
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• pp.513-518
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• 1999

In this study, geometrical similarity conditions for drills of various diameters are discussed. The effect of geometrical similarity on the chip shape and forces of different sized conventional drills has been experimentally confirmed. Drilling tests are carried out for SM45C by using the conventional HSS drills. The torque and thrust forces are measured and compared with those chip forms. Chip shape in drilling are affected by three factors being flow angle, side and up curl of the chip. It is found that the feedrate and drill diameter are more affected than cutting speed on the chip form and cutting forces. The similarity conditions gives easily to estimate the chip shape, the thrust and the torque for drills of different diameters.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.9 no.6
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• pp.118-126
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• 2000

In this study, geometrical similarity conditions for drills of various diameters are discussed. The effect of geometrical similarity on the chip shape and forces of different sized conventional drills has been experimentally confirmed. Drilling tests are carried out for SM45C by using the conventional HSS drills. The torque and thrust forces are measured and compared with those chip forms. Chip shape in drilling are affected by three factors being flow angle, side and up curl of the chip. It is found that the feedrate and drill diameter are more affected than cutting speed on the chip form and cutting forces. The similarity conditions gives easily to estimate the chip shape, the thrust and the torque for drills of different diameters.

• IE interfaces
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• v.7 no.3
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• pp.155-168
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• 1994

In computer integrated manufacturing environment, tool management plays an important role in controlling tool performance for machining operations. Knowledge of tool behavior during the cutting process and effective tool-behavior prediction contribute to controlling machine costs by avioding production delays and off-target parts due to tool failure. The purpose of this paper is to review and develop the tool condition monitoring scheme for drilling operation to assure a fast corrective response to minimize the damage if tool failures occur. If one desires to maximize system through-put and product quality as well as tooling resources, within an economic environment, real-time tool sensing system and information processing system can be coupled to provide the necessary information for the effective tool management. The example is demonstrated as to drilling operation when the aluminum composites are drilled with carbide-tipped HSS drill bits. The example above is limited to the situation that the tool failure mode of drill bits is wear.

• Journal of the Korean Society for Precision Engineering
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• v.21 no.3
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• pp.15-21
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• 2004

Composite materials are widely used to make all kinds of machine parts, internal and structural materials of cars, aerospace industries, building structures, ship materials, sporting goods and others. It is worth the while to use composite materials as various substitutions when compared with others. But the use is limited in the field of the mechanical processing because of its difficulties in processing. Thus, it is proved that the surface is rough in and out of the hole processing the GFRP with HSS drill in the vertical machining center.

• Journal of the Korean Society for Precision Engineering
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• v.12 no.8
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• pp.27-38
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• 1995

For solving troubles happened during the drilling process with carbon fiber epoxy composite materials(CFRP) by using HSS drill, a few types of diamond gift electroplated drills are manufactured, and machinability of these drills is experimented with a variety of cutting speed and feed rate. These drills have some advantages of good wear resistant and the conception of grinding process. As a result, using of these drills improves both troubles being caused by tool wear and damage of exit surface depending on fiber stacking angle. It is desirable that cutting conditions for the cutting thickness per revolution must be set under 0.01mm when the size of a diamond grit is # 60 .approx. 80.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.17 no.3
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• pp.7-15
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• 2018

Drilling processes require a cutting monitoring function that can be analyzed and gives feedback about strange conditions, tool collision and tool wear in real time. In this study, we proposed a drill monitor using the torque from the main spindle in CNC machine tools and a PROFIBUS network as a PLC-based interface. This paper studied drilling torque changes depending on drill size, the repetition cutting of the drilling and the drill's wear in the same cutting conditions. The material of the drills was high speed steel (HSS) and uncoated. The drills chosen were 2.7 mm, 6.7 mm, and 10.0 mm in diameter. These drills were selected because they had basic holes for their taps.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2003.06a
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• pp.1764-1767
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• 2003

It is widely used in composite materials like several mechanical parts. aerospace industries. internal and structural materials of cars, building structures. ship materials and sporting goods. but it is insufficient to apply in field of mechanical processing. Therefore. GFRP which is possible to use in industrial field was examined about cutting force. tool wear condition of cutting, chip shape. surface roughness and inlet or outlet shape of processing parts with changing cutting condition and using HSS drill which is in vertical machining center in this paper.