• Journal of the Korean Society of Manufacturing Process Engineers
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• v.3 no.2
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• pp.10-17
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• 2004

A real depth of cut in deformed zone has larger than an ideal depth of cut. So the heat generated during grinding operation makes the deformation of a workpiece surface as convex farm. Consequently the workpiece surface remains a geometric error as concave form after cooling In this study, the grinding force and the geometric error were examined in surface grinding. Through magnitude and mode of geometric error were evaluated according to grinding conditions, an optimal grinding condition was proposed to minimize the geometric error In addition, the relationship between the geometric error and the grinding force was examined. Due to least square regression, It was possible to predict the geometric error by using the grinding force.

• Composites Research
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• v.13 no.5
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• pp.44-49
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• 2000

Although the net-shape molding of composites is generally recommended, molded composites frequently requires cutting or grinding due to the dimensional inaccuracy for precision machine elements. The surface roughness and cutting force were also measured to investigate the surface grinding characteristics of the composites using the vitrified bonded wheel (WA, GC). The experiments were performed dry grinding conditions with respect to cutting speed, feed speed, depth of cut of the stacking sequence $[O]_{nT.}$ From the experimental investigation, the optimal conditions both the vitrified bonded wheel WA and GC for the surface grinding are suggested.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2002.10a
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• pp.155-159
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• 2002

This paper has studied to obtain the grinding characteristics and optimal grinding conditions of ceramics in the grinding with diamond wheel by Taguchi method. Feed rate was most important factor to the surface roughness. In the case of 4{Si_3}{N_4}$ and ${A1_2}{O_3}$, surface roughness value were small at 3m/min of feed rate. In the case of $ZrO_2$. surface roughness value was small at 4m/min of feed rate. Surface roughness have much influenced by major load for the :ii3N4 and $ZrO_2$. On the other hand, ${A1_2}{O_3}$ have more influenced by grain shedding of brittle fracture phenomenon. The major factors affecting the surface roughness and the optimum grinding conditions were obtained with minimum experiment using Taguchi method.

• Transactions of the Korean Society of Machine Tool Engineers
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• v.13 no.2
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• pp.9-16
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• 2004

Because a generated heat during grinding operation makes a serious deformation on a ground surface as a convex form, a real depth of cut in deformed zone has larger than an ideal depth of cut. Consequently, the ground surface has a geometric error as a concave form after cooling the workpiece. In this study, the force and the geometric error of surface grinding were examined. From evaluating magnitude and mode of the geometric error according to grinding conditions, an optimal grinding condition was proposed to minimize the geometric error. In addiction the relationship between the geometric error and the grinding force was found out. Due to least square regression it was able to predict the geometric error by using the grinding force.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.24 no.2 s.173
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• pp.338-346
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• 2000

Although the net-shape molding of composites is generally recommended, molded composites are frequently required cutting or grinding due to the dimensional inaccuracy for precision machine elements . During the composite machining operations such as cutting and grinding, the temperature at the cutting point may increase beyond the allowed limit due to the low thermal conductivity of composites, which might degrade the matrix of composite. Therefore, in this work, the temperature at the cutting point during cut-off grinding of carbon fiber epoxy composites was measured. The cutting force and surface roughness were also measured to investigate the cut-off grinding characteristics of the composites. The experiments were performed both under dry and wet grinding conditions with respect to cutting speed and feed rate. From the experimental investigation, the optimal conditions for the composite cut-off grinding were suggested.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.18 no.5
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• pp.443-448
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• 2009

The roughness models have developed to describe the grinding behaviour and predict the final quality of workpiece. The model forms of the plunge grinding process are generally established with initial and steady state model form in accordance with the accumulated metal removal. The steady state roughness model form are based on the grinding condition and specific parameters are used to show the influence of it according to the grinding process such as the equivalent chip thickness and accumulated metal removal. However, the models have been developed in past are not considered the effect of changing the grinding conditions in the same batch. In this paper, the roughness model form to consider the effect of changing grinding condition is proposed and the performance of proposed model is evaluated based on the experimental results.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1996.11a
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• pp.95-99
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• 1996

The form accuracy of parts has become an important parameter. Therefore dimensional tolerance and geometric tolerance are used in design to satisfy required quility and functions of parts. But the informations for machining conditions, which can satisfy the assigned geometric tolerance in design, are insufficient. The objectives of this research are to study the effects of the grinding parameters such as traverse speed, work speed, depth of cut, and dwell time on the after-ground workpiece shape, and to find out the major parameters among these parameters. Finally, a methodology is proposed for getting the optimal grinding condition for precision workpiece The results are as follows; The effects of work speed and depth of cut on workpiece shape are ignorable compared to the effect of traverse speed. These is the optimal dwell time depending on the traverse speed. The optimal dwell time is decreasing when the traverse speed is increased.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.10 no.3
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• pp.19-27
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• 2011

A weaving machine for texture industry uses a lot of needles and the nib of these needles is necessary to be kept with sharp edge. The re-grinding of the needle by a special purpose of the grinding wheel can be selected for achieving this aim. This study focused on the manufacture and performance assessment the special grinding wheel. A forming mold for the grinding wheel was designed and a sintering process for furnace process control was established. Manufactured wheels were tested for determining suitable grade of the wheel. The selection of optimal grinding conditions was achieved by a response surface method and a genetic algorithm.

• Journal of the Korean Society for Precision Engineering
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• v.16 no.6
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• pp.160-165
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• 1999

In surface grinding, the conditions of the grinding wheel give a significant effect on the ground workpieces comparing with other metal removal provesses. In this paper, to assist the development, a non-contacting optical method by the laser beam is introduced. The in-process measurement of scattering intensities has been made during surface grinding processes and the surface textures of wheel working surfaces are captured. Also, in order to determine the dressing time monitoring method of a grinding wheel, a three-dimensional computer simulation of the grinding operation has been attempted based on the contact mechanism and the surface-shaping system between the grinding wheel and the workpiece. The optimal dressing time is determined by the amount of the grain wear and work surface roughness.

• Journal of the Korea Society for Simulation
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• v.3 no.1
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• pp.167-178
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• 1994

For the identification of the optimal operating conditions of phosphoric acid plant, an intelligent simulation was performed based on the dissolution reaction of phosphate rock. A phosphoric acid plant consists of three main processes : ball-mill grinding process, rock reaction process and slurry filteration process. The grinding and filteration processes are relatively simple processes and most of the simulation works are on the reaction process. The practical operation data of phosphoric acid plant at Namhae Chemical Corp. were utilized in the simulation. The operation of the phosphoric acid plant is highly dependent on the heuristics of operators and so the expert system technology was employed. The operation of phosphoric acid plant varies with the origin of phosphate rock. Results of the simulation showed the optimal values of major process variables and optimal operating conditions. The knowledgebase for the expert system was constructed based on the interview with the experienced plant operators.