• 제목/요약/키워드: Linear wear rate

검색결과 29건 처리시간 0.025초

다경간 전열관의 난류 가진에 의한 마모특성 연구 (Wear Characteristics of Multi- span Tube Due to Turbulence Excitation)

  • 김형진;성봉주;박치용;유기완
    • 한국소음진동공학회논문집
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    • 제16권9호
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    • pp.904-911
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    • 2006
  • A modified energy method for the fretting wear of the steam generator tube is proposed to calculate the wear-out depth between the nuclear steam generator tube and its support. Estimation of fretting-wear damage typically requires a non-linear dynamic analysis with the information of the gap velocity and the flow density around the tube. This analysis is very complex and time consuming. The basic concept of the energy method is that the volume wear rate due to the fretting-wear phenomena Is related to work rate which is time rate of the product of normal contact force and sliding distance. The wearing motion is due to dynamic interaction between vibrating tube and its support structure, such as tube support plate and anti-vibration bar. It can be assumed that the absorbed work rate would come from turbulent flow energy around the vibrating tube. This study also numerically obtains the wear-out depth with various wear topologies. A new dissection method is applied to the multi-span tubes to represent the vibrational mode. It turns out that both the secondary side density and the normal gap velocity are important parameters for the fretting-wear phenomena of the steam generator tube.

다경간 전열관의 난류 여기에 의한 마모특성 연구 (Wear Characteristics of Multi-Span Tube Due to Turbulence Excitation)

  • 김형진;유기완;박치용
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2005년도 추계학술대회논문집
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    • pp.919-924
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    • 2005
  • Fretting-wear caused by turbulence excitation for KSNP(Korea standard nuclear power plant) steam generator is investigated numerically. Secondary sides density and normal velocity are obtained by the thermal-hydraulic data of the steam generator. Because nonlinear finite element analysis is complex and time consuming, work rate is estimated by using linear analysis for simple straight 2-span tube. Wear volume and depth by using work rate calculation are estimated. Span length, secondary side fluid density and normal velocity are adopted to study the effects on the fretting-wear by turbulence excitation. When secondary sides density and normal velocity is increased, It turns out that secondary side density and normal gap velocity are very important paramater for fretting-wear phenomena of the steam generator.

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A study on wear parameter of proceeding bearing

  • Tuan, Nguyen Anh;Hung, Pham Van;Ho, Phan Thach
    • 한국윤활학회:학술대회논문집
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    • 한국윤활학회 2002년도 proceedings of the second asia international conference on tribology
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    • pp.107-110
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    • 2002
  • In this paper the result of investigation of wear of proceeding bearing is presented. Different parameters as sliding speed, load, materials capacity etc, have influence on the Tribological behavior of proceeding bearing. The wear of proceeding bearings of various issues is determined and analyzed.

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분류에 의한 SLURRY 마멸 (Slurry Wear Test on the Liquid Jet)

  • 우창기;조견식
    • 한국공작기계학회논문집
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    • 제11권5호
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    • pp.88-92
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    • 2002
  • This research is about slurry wear of SM45C and SUS304, which using standard sand and KUM river sand. The results are as follows ; 1. Mass loss rates of both standard sand and KUM river sand were linearly increased as increasement of time and velocity. 2. The average diameter of sand from relatively, less wear rate and portion of larger particles. 3. Wear resistance was linear with time and velocity of liquid jet regardless of type of sand. Also, it was able to evaluate with the formula, $HV^2$/E calibrated with n, the velocity index. 4. The wear surface in liquid jet experiment was smooth. The maximum wear depth was observed at the location 2~4mm apart from the center in the condition of $90^{\circ}$ of collision angle 6mm of nozzle diameter, and 20mm of collision distance. The sectional shape in radial appeared as 'W'shape.

금강 토사에 의한 SLURRY 마멸 (Slurry Wear of Sand from the Kum River)

  • 우창기;조견식;김대업;강동명;이하성
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 2001년도 춘계학술대회 논문집
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    • pp.798-801
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    • 2001
  • This research is about slurry wear of SM45C and SUS304, which using standard sand and KUM river sand. The results are as follows ; 1. Mass loss rates of both standard sand and KUM river sand were linearly increased as increasement of time and velocity. 2. The average diameter of sand from relatively, less wear rate and portion of larger particles. 3. Wear resistance was linear with time and velocity of liquid jet regardless of type of sand. Also it was able to evaluate with the formula, HV2/E calibrated with n, the velocity index. 4. The wear surface in liquid jet experiment was smooth. The maximum wear depth was observed at the location, 2~4mm apart from the center in the condition of 90$^{\circ}$of collision angle 6mm of nozzle diameter, and 20mm of collision distance. The sectional shape in radial appeared as 'W' shape.

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Wear Property of $Al_2O_3-Particle-Reinforced$ Aluminium Composite

  • Sahin, Y.;Motorcu, A.Riza
    • 한국윤활학회:학술대회논문집
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    • 한국윤활학회 2002년도 proceedings of the second asia international conference on tribology
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    • pp.201-202
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    • 2002
  • The abrasive wear behaviour of $Al_2O_3$ particle-reinforced aluminium composite was investigated. The wear rate of the composite and the matrix alloy has been expressed in terms of the applied load, sliding distance and particle size using linear factorial design approach.

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Scf 파라메타에 의한 세라믹 마멸 평가 (The Assessment of Ceramic Wear by the Parameter Scf)

  • 김상우;김석삼
    • 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}$.

세라믹 마멸에 있어서의 새로운 파라메터 제안 (I) 질화규소와 지르코니아의 마찰$\cdot$마멸 특성 (A Propotition of a New Parameter in Ceramic Wear(I) Friction and Wear Characteristics of Silicon Nitride and Zirconia)

  • 김석삼;김상우
    • 대한기계학회논문집
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    • 제17권6호
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    • pp.1441-1455
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    • 1993
  • 본 연구에서는 최신기법에 의해서 제조된 HIP제 질화규소와 지르코니아를 실험재료로 하여 무윤활하에서의 미끄럼마찰·마멸실험을 수행하여 마찰·마멸특성을 규명하고, SEM을 이용한 마멸면의 미시적 관찰을 통해서 세라믹의 마멸기구를 조사하 여 세라믹마멸기구의 마멸모델을 제시하고자 한다. 제시된 마멸모델에서 파괴역학을 도입하여 이론해석과 고찰을 수행하여 보다 실용적인 세라믹의 마멸율울 평가할 수 있 는 새로운 무차원 파라메터를 제안하고자 한다.

탄소주강과 경강선재간의 미끄럼 마멸특성 (The Sliding Wear Characteristics of Carbon Steel Castings against High Carbon Steel Wire Rods)

  • 류중북;채영훈;김석삼
    • 한국윤활학회:학술대회논문집
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    • 한국윤활학회 2001년도 제33회 춘계학술대회 개최
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    • pp.319-326
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    • 2001
  • The sliding wear characteristics of carbon steel castings were Investigated using a ball on disk type tester. The experiment was conducted using high carbon steel wire rods as ball material and carbon steel castings as disk material and different operating conditions, at room temperature under a lubrication and dry conditions. The results showed that the carbon steel castings appeared average wear volume Is lowed after annealing under a lubrication conditions and wear curve linear Increased. The specific wear rate of carbon steel castings Increased with wire diameter lubrication and dry also Increased 125 times In Ory. The sliding wear mechanism were Investigated due to fatigue wear lubrications and abrasive wear dries also wire Included fatigue and abrasive wear by plastic flow.

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Wear Behavior of Silica filled Styrene-Butadiene Rubber: A Comparative Study Between the Blade-Type and Akron-Type Abrader

  • Gi-Bbeum Lee;Dongwon Kim;Seowon Lee;Seonhong Kim;Myung-Su Ahn;Bismark Mensah;Changwoon Nah
    • Elastomers and Composites
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    • 제58권4호
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    • pp.179-190
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    • 2023
  • The effect of the particle size and silica structure on the wear behavior of Silica/Styrene-Butadiene Rubber (SBR) compounds was investigated using a blade-type abrader and the findings were compared with those obtained with an Akron abrader. The compensated characteristic parameter (Ψc), which was the contributory factor of the combined effect of the particle size and filler structure, was introduced. This parameter was found to exhibit a linear relationship with the Young's modulus. The Young's modulus correlated more with Ψc than the uncompensated characteristic parameter (Ψ) modeled for carbon black. The wear rate and volume loss measured using a blade-type abrader and Akron abrader were respectively observed to be inversely proportional to Ψc, that is, the wear resistance of Silica/SBR compound improved as the particle size became smaller and the silica structure became intricate. The coefficient of determination (R2) obtained from the linear relationship between Ψc and wear rate was higher than those between Ψc and volume loss for the Silica/SBR compound. Thus, the blade-type abrader exhibited high potential to be used for accurately evaluating the effect of particle size and structural properties of silica on the wear behavior of SBR compounds.