• Proceedings of the Korean Society of Precision Engineering Conference
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• 2001.04a
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• pp.1105-1108
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• 2001

In these days, according s the increase of technological development the part demension goes up for ultra-precision. It is grinding behavior that is important processing which directly influences by machining accuracy at product quality with the net shape manufacturing. In this study, by using CBN wheel an analysis carried out for workpiece's profiles and its characteristics by measuring grinding force and surface roughness. Workpiece materials were used STD11, SUS304 and STB2 varing condition of feedrate and depth of cut.

• Proceedings of the KIEE Conference
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• 2015.07a
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• pp.1517-1518
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• 2015

The paper deals with the real time sensing of a chatter vibration in grinding machine line of automobile bearings using machine black box. The chatter vibration plays bad role in machining quality such as high roughness as well as tool life and machine failure. In this paper, the vibration signals of the automobile hub bearing in the grinding process are shown in the time domain and frequency domain. Through the vibrational signals, chatter vibration badness is detected using machine black box. Therefore, machine black box can be applied to the real time detection of the grinding process in engineering fields.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2000.04a
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• pp.447-452
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• 2000

The grinding plays a key role which decide the quality of a product finally. But the grinding process is very irregular, so it is very difficult to analyse the process accurately. Therefore it is very important in the aspect of precision and automation to reduce the idle time and to decide the proper dressing time by visualizing. In this study, we choose the direct method of observation by making use of computer vision, and apply pattern classification technique to the method of measuring the wheel surface. Pattern classification technique is proper to analyse complex surface image. We observe the change of the wheel surface by making use of the gray level run lengths which are representative prince in this technique.

• Journal of Mechanical Science and Technology
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• v.14 no.10
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• pp.1114-1121
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• 2000

A flexible disk grinding process model was developed based on the dynamic relationship proposed by Kurfess and the influence of the major system parameters which potentially affect the grinding process was studied. Due to the process complexities, several new parameters were assumed to be kinematically dependent on the geometric layouts of the process. Different process stages had been defined depending on the kinematic relationships between the grinding disk and workpiece. A trend of depth of cut was simulated using the proposed model and compared with the empirically measured data in two dimensions. Due to a poor prediction capability of the first model, a modified model was proposed and a better performance has been proved to reveal a closer description of processed surface quality. Also a deflection length has been verified using a different analytical approach.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2002.10a
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• pp.57-60
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• 2002

The high precision spindle is essential fer mass and low cost production of aspherical glass lens. Especially, in the grinding process of micro glass lens the performance of the spindle determine the machined surface quality. For the aspheric micro glass lens grinding, we design and make a high precision spindle. We use air bearings for high speed and low motion errors of the spindle. And the driving mechanism is an air turbine to remove heat generation. In this study, we make basic performance requirements of the spindle through benchmarking. And we confirm the requirements by basic machining test. We test air consumption, static stiffness, run-out and vibration of the spindle.

• Cement
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• s.130
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• pp.26-34
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• 1993

For the purpose of increasing the quality of products and reducing the grinding cost of cement clinker, some aids were studied. Some of common grinding aids, such as Ethylene Glycol, Diethylene Glycol, Triethanolamine and so on, lead to the environmental

• Journal of the Korean Society for Precision Engineering
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• v.21 no.9
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• pp.196-203
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• 2004

SL(Stereolithography) part is made by piling up thin layers which causes the stair stepping effect at the surface of SL parts. The effect brings about excessive surface roughness and cuts down the merits of using SL part. Hence, additional post-machining finishing such as traditional grinding is required. But the traditional post-machining is detrimental to part geometry and time consuming. In this study, therefore, a paraffin coating and grinding post-machining is newly proposed to improve the surface quality of SL fart. The paraffin which has suitable properties for the proposed post-machining is coated all over the part surface. By grinding the only over-coated paraffin based on boundary of the SL part surface, the surface roughness can be improved without any damage on the part. Also, it is verified that SL part finished by the proposed post-machining process can be applied for rapid tooling as pattern through manufacturing silicon rubber molding and casting test.

• Design & Manufacturing
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• v.17 no.2
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• pp.33-41
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• 2023

Metal raw materials and chemical additives, which are raw materials for secondary batteries, are pulverized by the high-speed rotation of the Grinding Disc of the Classifier Separator Mill (CSM). Grinding discs are required to withstand abrasion, corrosion, high-speed rotational force and impact. In order to analyze the stability of domestic and foreign grinding discs, quality tests including surface roughness, surface lubrication, surface state measurement, and surface 3D shape measurement were analyzed. When producing developed products, it shows that excellent products can be produced.

• International Journal of Precision Engineering and Manufacturing
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• v.8 no.2
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• pp.38-43
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• 2007

This paper describes ultrasonically assisted grinding used to obtain a glossy surface quickly and precisely. High-quality surfaces are required for plastic injection molding dies used in the production of plastic parts such as dials for cellular phones. Traditionally, in order to finish the dies, manual polishing by a skilled worker has been required after the machining processes, such as electro discharge machining (EDM), which leaves an affected layer, and milling, which leaves tooling marks. However, manual polishing causes detrimental geometrical deviations of the die and consumes several days to finish a die surface. Therefore, a machining process for finishing dies without manual polishing to improve the surface roughness and form accuracy would be extremely valuable. In this study, a 3D positioning machine equipped with an ultrasonic spindle was used to conduct grinding experiments. An electroplated diamond tool was used for these experiments. Generally, diamond tools cannot grind steel because of excessive wear as a result of carbon atoms diffusing into bulk steel and chips. However, ultrasonically assisted grinding can achieve a fine surface (roughness Rz of $0.4{\mu}m$) on die steel without severe tool wear. The final aim of this study is to realize mirror surface grinding for injection molding dies without manual polishing. To do this, it is necessary to fabricate an electroplated diamond tool with high form accuracy and low run-out. This paper describes a tool-making method for high precision grinding and the grinding performance of a self-electroplated tool. The ground surface textures, tool performance and tool life were investigated A ground surface roughness Rz of 0.14 um was achieved Our results show that the spindle speed, feed rate and cross feed affected the surface texture. One tool could finish $5000mm^2$ of die steel surface without any deterioration of the ground surface roughness.

• Journal of Biosystems Engineering
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• v.22 no.4
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• pp.439-450
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• 1997

Most of Korean feed mill has a pregrind system which was suitable for the processing of less number of ingredients and finished products, and good for the mash type feed product. But industries has been changed in production volume and cost, and also from mash to further processed products such as pelleted and extruded. Therefore, Korea feed industries now should change the process, especially the grinding system from the current pregrind to other grind system, but this change will cost a lot of investment and also loosing current grinding system, and should have production shut down during the construction period. To solve these problems, combined grinding system based on a new model mill has been developed. The combined grind system is combination of pregrind and postgrind system, which has the advantages of those two grind systems, and also which can allow to utilize existing pregrind system continuously without any production interruption due to new postgrind system construction. This newly developed model has been applied to the feed mill expansion project of `B`feed company in 1994, and it was very successful application and showed excellent results as we intended. The new model mill, combined grind system applied can save fixed asset investment because old pregrind system can be used as is, and also can reduce production cost and improve product quality. And the possibility of critical production shut down can be much lowered. Within this new grinding model development, multi-screen combination system has been developed for the better grinding texture quality and safer operation. This new model mill with combined grind system will be applied by most feed manufacturing plant and may enhance their production competitiveness, and the further study and development should be continued.