• Journal of Welding and Joining
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• 제12권3호
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• pp.71-81
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• 1994

Laser cutting is experiencing a rising worldwide acceptance in the industry. Expert systems are necessary for the systematic arrangement and searching of experimental data existing in journal papers, job handbooks, etc.. This paper proposes an expert system for the selection of the appropriate laser cutting variables from the available database. Optimum cutting conditions according to the given cutting velocity were searched and qualitative comments which are difficult to be used as database variables were shown at each velocity using the binary and fuzzy inference. These comments could be informative to unskilled operators of the laser cutting process. Typical cutting conditions of the mild steel and stainless steel were included and the working range and quality variations were displayed graphically. The proposed algorithm was implemented in an IBM compatible personal computer as an expert system for CO$_{2}$ laser cutting to derive the optimum cutting conditions by using the turbo prolog.

• 한국생산제조학회지
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• 제18권5호
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• pp.498-506
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• 2009

An experimental study was performed to select cutting parameters for better quality-products in hard metals such as steels. Usually, a hard metal can be cut with a rotary cutting knife and the process provides a good cutting quality result. However, the cutting machine is much sensitive in cutting conditions because of its complicated mechanism. By this reason, careful processing conditions must be taken to improve the quality of the products. This experimental study for better quality products with a rotary cutting knife was carried out with two main factors; cutting speeds and cutting and pooling forces. A two-dimensional profile measuring instrument is used to evaluate its cutting faces and the effects of processing factors are analyzed by a commercial software.

• 한국정밀공학회지
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• 제21권6호
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• pp.77-83
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• 2004

Cutting by a high speed laser cutting machine is one of most effective technologies to improve productivity. This paper has studied to obtain the cutting characteristics and optimal cutting conditions in a high speed feeding type laser cutting machine by Tacuchi method in design of experiments. A Lf(34) orthogonal array is adopted to study the effect of adjustment parameter. The adjustment parameters consist of cutting speed, laser power, laser output duty and assistant gas pressure. And the quality feature is selected as surface roughness of sheet metal. Variance analysis is performed in order to evaluate the effect of adjustment parameters on the quality feature of laser cutting process.

• 한국기계가공학회지
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• 제12권3호
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• pp.76-80
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• 2013

This paper reports some experimental results on the machining performance of ground & non-ground milling inserts. Five kinds of milling inserts were manufactured without grinding process and one milling insert was manufactured with grinding process. Machining experiments were carried out to compare the performance of ground & non-ground inserts. This experimental result indicate that tool wear, cutting force and surface roughness of the each tool. From the result five milling inserts that have non-grinding process and one milling insret that have grinding process compared appear.

• 한국생산제조학회지
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• 제9권1호
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• pp.81-87
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• 2000

A variable cutting speed control model was developed to be implemented for the flexible disk grinding process Control algorithm was based on the error referred by the discrepancy between current disk angle and intended one that are pro-posed to produce desired resulting depth of cut. Controller was implemented in two different aspect One was to initiate the control law from the beginning while the other was to activate as soon as the disk start to produce ground surface i.e. The beginning of the between edges stage. Several performance analysis were conducted comparing various process parameters such as cutting force disk angle depth of cut and disk speed with respect to process transition time Tentative results revealed that controller implemented from the earlier stages of the process showed better performance than the other revealed that controller implemented from the earlier stages of the process showed better performance that the other.

• 한국시뮬레이션학회:학술대회논문집
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• 한국시뮬레이션학회 1998년도 추계학술대회 및 정기총회
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• pp.204-208
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• 1998

The fundamental issues to evaluate machine tool's performance through simulation pertain to the physical models of the machine tool itself and of process while the practical problems are related to the development of the modular software structure. It allows the composition of arbitrary machine/process models along with the development of programs to evaluate each state of machining process. Surface roughness is one of the fundamental factors to evaluate machining process and performance of machine tool, but it is not easy to evaluate surface roughness due to its tribological complexity. This paper presents an algorithm to calculate surface roughness considering cutting geometry, cutting parameters, and contact dynamics of cutting between tool and workpiece as well as tool wear in turning process. The designed virtual machining system can be used to evaluate the surface integrity of a turned surface during the design and process planning phase for the design for manufacturability analysis of the concurrent engineering.

• 한국시뮬레이션학회논문지
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• 제8권1호
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• pp.19-33
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• 1999

The fundamental issues to evaluate machine tools performance through simulation pertain to the physical models of the machine tool itself and of process while the practical problems are related to the development of the modular software structure. It allows the composition of arbitrary machine/process models along with the development of programs to evaluate each state of machining process. Surface roughness is one of the fundamental factors to evaluate machining process and performance of machine tool, but it is not easy to evaluate surface roughness due to its tribological complexity. This paper presents an algorithm to calculate surface roughness considering cutting geometry, cutting parameters, and contact dynamics of cutting between tool and workpiece as well as tool wear in turning process. This proposed algorithm could be used in the designed virtual machining system. The system can be used to evaluate the surface integrity of a turned surface during the design and process planning phase for the design for manufacturability analysis of the concurrent engineering.

• 한국의류산업학회지
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• 제13권2호
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• pp.269-278
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• 2011

This study aims at setting up productive capacity which can be usefully utilized for work management of apparel manufacturers. So as to achieve this goal, an apparel manufacturing company which has been operated by miniline system in Seoul was selected. Standard time and man-hour were calculated to create the accurate productive capacity by observing and measuring a work flow included cutting, sewing and finishing processes. And the result is as following. The standard time for each process was presented as cutting process 47004.5s, sewing process 671050.5s and finishing process 22426.3s. And 15284.4ms was computed as total procession man-hour per day of the manufacturer which is organized of 16 people. Also, the procession man-hour for each process was revealed as cutting process 396.7ms(2.6%), sewing process 14509.3ms(94.9%) and finishing process 378.5ms(2.5%). +Surplus was found in the productivity for each process included the cutting process(outshell, lining and seam process), the sewing process(preparation and arrangement process) and the finishing process. But, additional man-hour 52436.18ms was required because the productive capacity was calculated as -surplus(-13.9%) in the sewing process(part and assembly process). Therefore, a work schedule was planned based on the previous result. However, loading can be ideal when a capacity and a load become '0'. The object company should find the way to reduce allowance(26.25%) of the sewing process through reconstruction of consciousness and improvement in functions with analyzing works of operators. Also, they need to consider an additional supplement of the personnel.

• 한국CDE학회논문집
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• 제2권4호
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• pp.267-275
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• 1997

A ship-block cutting module is being developed as part of a computational system for a ship design. The module supports product-information to other modules in design process and displays ship-blocks in cutting-operation. Welding-information is essential to process-planning and scheduling. In the module, ship-blocks are modeled by Plate-Objects and then divided into several cutting pieces. The module automatically creates Welding-Objects containing welding-information in the process. Since the module is connected to WWW(World Wide Web), users in various platforms can access the models simultaneously In addition, users can check manufacturing constraints by inspecting a virtual model.

• 소성∙가공
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• 제18권2호
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• pp.144-149
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• 2009

Recently, the monitoring technology of machining process is very important to improve productivity and quality in manufacturing filed. Such monitoring technology has been performed to measurement using vibration signal, acoustic emission signal and tool dynamometer. However, micro machining is limited small-scale parts machining because micro tool is very small and weakness to generate signal in micro machining process. Therefore, this study has efficient sensing technology for real monitoring system in micro machine that is proposed to supplement a disadvantage of single-sensor by multi sensor. From experimental result, it was evaluated tool wear and cutting situation according to repetitive slot cutting condition and changing cutting condition, and it was performed monitoring spindle rpm and condition according to compare acceleration signal with current signal.