• Transactions of the Korean Society of Mechanical Engineers
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• v.19 no.7
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• pp.1555-1562
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• 1995

This study represents the non-dimensional cutting force model. With the non-dimensional cutting force model it is possible to estimate efficiently the maximum cutting force during one revolution of cutter. Using the non-dimensional cutting force model, the feed rate and spindle speed are adjusted so as to satisfy the maximum cutting force and maximum machining error. To verify the accuracy and efficiency of the non-dimensional cutting force model, a series of experiments were conducted, and experimental results proved and verified the non-dimensional cutting force model. The NC toolpath verification system developed in this paper uses the non-dimensional cutting force model, so that it is effective for calculating the cutting force and adjusting the cutting conditions.

• Journal of the Korean Society for Precision Engineering
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• v.12 no.6
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• pp.112-119
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• 1995

Early fracture and cutting force of ceramic tool for hardened STC3 steel was investigated in this study. It was found that early fracture of ceramic tool was mostly occurred before normal wear was progressed beyond a critical cutting speed and normal wear was performed under the critical cutting speed. The relationships among critical cutting speed, which was a cause of early fracture, suggested cutting cross section, that is, maximum thickness of cut and width of cut, and cutting force were examined. The following conclusions were obtained: (1)Critical cutting speed showed a high value in the case of small maximum thickness of cut and large nose radius, but was not influenced by width of cut, (2)Principal, feed and radial force, respectively, showed the proportional value to constant cutting area, width of cut and maximum thickness of cut orderly, (3)Occurrence of early fracture was dependent upon radial force.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2001.04a
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• pp.188-191
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• 2001

Generally, main factors of tool damage are cutting speed, feed rate and depth of cut. The increase of those factors can cause tool breakage or worsen product quality such as machining accuracy deterioration. Those three factors are concerned with cutting force. Cutting force reaches at its maximum value when cutter blade cuts away the object directly, and it is the time when tool damages are at high probability. In this study, we detect the maximum cutting force affecting tool damage and control the maximum cutting force based on the measured peak force.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1993.10a
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• pp.428-433
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• 1993

In this paper, the fast algorithm to calculate cutting force of milling and its application to NC verification system have been studied. The fast force algorithm can calculate the maximum cutting force fastly during one revelotion of tool. The NC verification using the fast force algorithm can verify excessive cutting force which is the cause of deflection and breakage of tool, and can so adjust the feed rate as to manufacture with the maximum force criterion or maximum machining error criterion. So, the fast force algorithm has been added to the NC verification system, the NC verification system can verify the physical problems in NC code effectively.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2002.10a
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• pp.3-6
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• 2002

This paper presents the cutting simulation system for prediction and regulation of cutting force in CNC machining. The cutting simulation system includes geometric model, cutting force model, and off-line fred rate scheduling model. ME Z-map(Moving Edge node Z-map) is constructed for cutting configuration calculation. The cutting force models using cutting-condition-independent coefficients are developed for flat-end milling and ball-end milling. The off-line feed rate scheduling model is derived from the developed cutting force model. The scheduled feed rates are automatically added to a given set of NC code, which regulates the maximum resultant cutting force to the reference force preset by an operator. The cutting simulation system can be used as an effective tool for improvement of productivity in CNC machining.

• Proceedings of the Korean Radioactive Waste Society Conference
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• 2017.10a
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• pp.189-190
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• 2017

For the concept design of the device, a tool was made to test the simulated fuel rods and cutting force and the cutting force was measured. When 2-CUT and 3-CUT modules were used, the maximum force in 2-CUT at 12.5 mm/s speed change was $197.5kg_f$ and the maximum force at 3-CUT was $363.2kg_f$. The change of force in 2-CUT rapidly increases from about 1 second, and you can see that there are increase and decrease of the force change from about 5 seconds to 18 seconds, and it was rapidly decreased and the cut was made. The force change in 3-CUT has higher force at about 5 seconds later than 2-CUT at the speed of 12.5 mm/s, and you can see that it has the same tendency afterwards. If you search for the force at adequate speed from this cutting force test, 2-CUT module requires less slitting force than 3-CUT module, and the cutting time for 250 mm at 12.5 mm/s was 21 seconds, which can cut 4 m fuel rod in 5 minutes. But, there are cases of not completely slitting with 2-CUT module, so it is necessary to supplement this in the future through experiments.

• Journal of the Korean Society for Precision Engineering
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• v.17 no.5
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• pp.173-179
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• 2000

While a cutting tool is machining a workpiece at various cutting depth, the feedrate is usually selected based on the maximum depth of cut. Even if this selection can avoid power saturation or tool breakage, it is very conservative compared to the capacity of the machine tools and can reduce the productivity significantly. Many adaptive control techniques that can adjust the feedrate to maintain the constant cutting force have been reported. However, these controllers are not very widely used in manufacturing industry because of the limitations in measuring the cutting force signals. In this paper, turning force control systems based on the estimated cutting force signals are proposed. A synthesized cutting force monitor is introduced to estimate the cutting force as accurately as a dynamometer does. Three control strategies of PI, adaptive and fuzzy logic controllers are applied to investigate the feasibility of utilizing the estimated cutting force fur turning force control. The experimental results demonstrate that the proposed systems can be easily realized in CNC lathe with requiring little additional hardware.

• Journal of the Korean Society for Precision Engineering
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• v.7 no.2
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• pp.47-57
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• 1990

In-process recognition of the cutting states is one of the very important technologies to increase the reliability of mordern machining process. In this study, practical methods which use the dynamic component of the cutting force are proposed to recognize cutting states (i.e. chip formation, tool wear, surface roughness) in turning process. The signal processing method developed in this study is efficient to measure the maximum amplitude of the dynamic component of cutting force which is closely related to the chip breaking (cut-off frequency : 80-500 Hz) and the approximately natural frequency of cutting tool (5, 000-8, 000 Hz). It can be clarified that the monitoring of the maximum apmlitude in the dynamic component of the cutting force enables the state of chip formation which chips can be easily hancled and the inferiority state of the machined surface to be recognized. The microcomputer in-process tool wear monitor- ing system introduced in this paper can detect the determination of the time to change cutting tool.

• Tunnel and Underground Space
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• v.32 no.6
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• pp.386-396
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• 2022

To analyze the influence of variables of roadheaders, the linear cutting testing data of pick cutter were collected from the former literatures. The input factors were set up as uniaxial compressive strength, cutting depth, cutting spacing, attack angle, skew angle, and output factors were determined as specific energy, average cutting force, maximum cutting force, average vertical force, and maximum vertical force. After composing a table of the design of experiment (DOE). The contribution level of each factor was calculated by analysis of variance (ANOVA). As a result, the factors having greatest influence on cutting force and specific energy were uniaxial compressive strength and cutting spacing.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.12 no.1
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• pp.9-14
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• 2013

In recent years, high hardness steel is used for most of the material in many areas including aircraft, nuclear power, space exploration and automotive parts. Low CBN tools are widely used in industrial field which can effectively process high hardness steel of HRC 45 or harder. The results of this study demonstrated, when high hardness steel, SCM440 is turned with Low CBN tools coated with TiN and TiAlN coatings respectively, that both the thrust force and cutting force tends to increase with more increase in cutting force than thrust force, as the feed rate increases at constant cutting speed. In addition, the size of the cutting force and thrust force does not change with the increased cutting speed at the same feed rate, but the tool life is reduced if the cutting speed is increased to shorten the machining time. Therefore, it is recommended to limit the cutting speed at 250 m/min maximum or less. Furthermore, comparing the cutting force of the three tools at the same cutting condition, Tin coating tool showed the smallest cutting force and Low CBN was the next, and the TiAlN coating tools showed the largest cutting force.