• Tribology and Lubricants
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• 제23권4호
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• pp.156-161
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• 2007

The friction test using disk-on-pad type was carried out and regression analysis with friction parameters was applied fur wear loss presumption of motorcycle break disk. The wear loss has an effect on the frictional factor such as applied load, sliding speed, and number of ventilated disk hole. However, it is difficult to know the mutual relation of these factors on wear loss of motorcycle break disk. From this study, the result was shown that the regression analysis equation containing 4 elements were constructed and this equation had a trust of 95% in wear loss presumption of motorcycle break disk. It is possible to apply for another automobile parts.

• 산업경영시스템학회지
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• 제43권3호
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• pp.95-100
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• 2020

Machines and facilities are physically or chemically degenerated by continuous usage. One of the results of this degeneration is the process mean shift. The representative type of the degeneration is wear of tool or machine. According to the increasing wear level, non-conforming products cost and quality loss cost are increasing simultaneously. Therefore a periodic preventive resetting the process is necessary. The total cost consists of three items: adjustment cost (or replacement cost), non-conforming cost due to product out of upper or lower limit specification, and quality loss cost due to difference from the process target value and the product characteristic value among the conforming products. In this case, the problem of determining the adjustment period or wear limit that minimizes the total cost is called the 'process mean shift' problem. It is assumed that both specifications are set and the wear level can be observed directly. In this study, we propose a new model integrating the quality loss cost, process variance, and production volume, which has been conducted in different fields in previous studies. In particular, for the change in production volume according to the increasing in wear level, we propose a generalized production quantity function g(w). This function can be applied to most processes and we fitted the g(w) to the model. The objective equation of this model is the total cost per unit wear, and the determining variables are the wear limit and initial process setting position that minimize the objective equation.

• 한국자동차공학회논문집
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• 제10권2호
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• pp.117-122
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• 2002

This study assesses the wear process of particle impingement erosion which is a major source of erosion among fluid power components. First, Bitter's theory was modified to simplify engineering calculations. Second, actual experiments were conducted to validate the modified equation. And the effect of concentration and size distribution of impinging particles was tested. Little deviation from the prediction of the modified equation was observed. To develop complete analytical approach to the erosion mechanism, further experimental data are required to establish a correlation with other engineering parameters.

• 한국감성과학회:학술대회논문집
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• 한국감성과학회 1997년도 한국감성과학회 연차학술대회논문집
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• pp.47-52
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• 1997

This study was carried out to investigate effects of fabric properties and the changes of microclimates on comfort sensations and to identify effective varuables on clothing wear comfort sensations. A wied range of nontreated and functionally treated woven fabrics, knits, and nonwoven fabrics and test garments made of them were used as specimens. Linear structural equation was used to analyze causal relation among the variables on a path diagram. The results were as follows: 1. Almost of causal relations among variables were significant excdpt the effects of fabric properties including air permeability and water-vapor permebility on the changes of microclimate temperature. 2. Fabric properties were most effective variables on clothing wear comfort sensations including thermal sensation, subjeceive wettedness, and overall comfort and therefore comfort sensations and fabric properties were identified for improving clothing comfort.

• 한국안전학회지
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• 제18권4호
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• pp.16-22
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• 2003

Generally the rupture of steam generator tubes proceeds from significant plastic deformation before failure. In this study, the burst pressures of damaged steam generator tubes were calculated from the plastic instability analysis with the finite element method. Two wear types, flat and circumferential types were considered. An equation for the burst pressure was proposed by using the strength reduction factor and the Svensson equation. The analysis results were compared with the experiment data from published references and they showed a good agreement with the experiment data.

• 한국윤활학회:학술대회논문집
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• 한국윤활학회 2001년도 제33회 춘계학술대회 개최
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• pp.15-21
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• 2001

This study assesses the wear process of particle impingement erosion which is a major source of erosion among fluid power components. First, Bitter's theory was modified to simplify engineering calculations. Second, actual experiments were conducted to validate the modified equation. And the effect of concentration and size distribution of impinging particles was tested. Little deviation from the prediction of the modified equation was observed. To develop an analytical approach to the erosion mechanism, further experimental data are required to establish a correlation with other engineering parameters.

• Tribology and Lubricants
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• 제12권1호
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• pp.56-65
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• 1996

The result of wear test for ceramic materials was assessed by Scf parameter to verify the usefulness of the proposed Scf parameter. Friction and wear tests were carried out with ball on disk type. The materials used in this study were HIPed Alumina $(Al_2O_3)$, Silicon carbide (sic), Silicon nitride $(Si_3N_4)$ and Zirconia $(ZrO_2)$. The tests were carried out at room temperature with self mated couples of ceramic materials under lubricated condition. Turbine oil was used as a lubricant. In this test, increasing the load, specific wear rates and wear coefficients of four kinds of ceramic materials had a tendency to increase. The wear coefficients of ceramic materials were in order of $Al_2O_3, SiC, Si_3N_4, ZrO_2$. Worn surfaces investigated by SEM had residual surface cracks and wear particles caused by brittle fracture. As the fracture toughness of ceramic materials was higher, wear resistance more increased. The roughness of worn surface had correlation with wear rate. The wear rate(W$_{s}$) and Scf parameter showed linear relationship in log-log coordinates and the wear equation was given as $W_s = 5.52 $\times$ Scf^{5.01}$.

• 대한기계학회논문집
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• 제10권2호
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• pp.223-231
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• 1986

본 연구에서는 공구현미경을 이용하여 간판하게 공구수명을 구할 수 있는 방법을 제시하기 위한 전 단계로서 공구의 마멸거동에 대하여 연구하였다. 공구의 마멸은 매우 복잡한 현상이며 대부분의 경우 주로 마멸의 누증이 공구를 파손에 이르 게 한다. 마멸의 형태중 마멸(abrasion wear)과 점착에 의하여 발생되는 측면마멸이 가공물의 표면조도, 정밀도 및 절삭동력에 미치는 영향과 측정상의 경의 때문에 공구 수명을 지배하는 주마멸인자로 취급되고 있다. 따라서 절삭시간에 대한 공구의 측면 마멸 거동을 분석하여 초경공구의 측면마멸유선의 직선모델을 구하고, 측면마멸유선의 일반모델을 확립하였다.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2008년도 춘계학술대회 논문집
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• pp.513-514
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• 2008

• Tribology and Lubricants
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• 제11권5호
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• pp.10-14
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• 1995

Over 300 equations and models were found in the leterature on friction and wear. No single equation on limited group of equations could be found for general on practical use. Recommandations are offered for improving the future yield of useful equatio