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Structural Analysis of Continuous Ship Unloader
Abdul Wasy,Atta Ur Rehman,Hye-Soo Kim,Sun-Ho Ha,Jung-Il Song 대한기계학회 2012 대한기계학회 춘추학술대회 Vol.2012 No.11
Continuous ship unloader (CSU) is used for uninterrupted transportation of material. Small scales to huge CSU structures are being used in process industries, power plants and harbors, depending upon transportation material stream rate. This study focused on design optimization after three-dimensional modeling in CATIA and finite element structural analysis of big CSU structure in ANSYS Workbench. For detailed analysis study, the big structure was divided in two portions. One is the upper section, which can be rotated on center post and it also facilitates translatory motion of sea leg. This section includes mast top, front tension bars, rare tension bar, mast frame and mast front. While the lower section rests on the earth and supports the upper part and also helps in transportation through conveyer belt. This section includes, center post, portal grinder, sea side and land side supports. The whole structure deals with heavy loads and high multi axial moments. Hence the actual structure was compared with optimized design and its was concluded that, optimized design have less stresses and deflections under same applied conditions in comparison of actual model.
Effect of Diamond like Carbon Coating Thickness on Stainless Steel Substrate
Abdul Wasy(압둘와지),Balakrishnan G(발라크리쉬난),Y.Q. Wang(왕일기),J.I. Song(송정일),S.H. Lee(이승훈),J.K. Kim(김종국),D.G. Kim(김도근),T.G. Kim(김태규) 대한기계학회 2013 대한기계학회 춘추학술대회 Vol.2013 No.5
Diamond like carbon coatings have excellent wear properties with high hardness. The hardness and adhesion properties vary with sp3/sp2 ratio and coating thickness. In this research, effect of coating thickness on stainless steel substrate has studied. Diamond like carbon coatings of 300nm, 500nm, and 650nm has deposited using Filter Cathodic Vacuum Arc System with Magnetron sputtered Chromium interlayer. The characterization includes, Field Emission Electron Microscopy, Raman spectroscopy, Tribology and Adhesion strength evaluation. It was concluded that, surface finish decreased with increase in coating thickness. Maximum ID/IG of 0.84 was obtained for 30nm diamond like carbon coated stainless steel. The minimum average friction coefficient of 0.115 was obtained for 500nm coating. Moreover, it was observed that, friction coefficient decrease with increase in coating thickness in initial phases, after certain time it increase directly proportional to thickness. For adhesion strength, LC1 was found good for 650nm and LC2 for 500nm respectively.
압둘와지지아(Abdul Wasy),발라크리쉬난(Balakrishnan G),김진우(Kim Jin-Woo),원천(Won Cheon),송정일(Jung-Il Song) 대한기계학회 2012 대한기계학회 춘추학술대회 Vol.2012 No.5-3
In this study, finite element analysis of LPG cylinder is performed to enhance the service life. Maximum von mises, longitudinal, hoop stresses and deformation is analyzed to predict the structural failure at services, Test, minimum burst and expected burst pressures of 2, 3, 6 and 8 MPa respectively. The main components of LPG cylinder are inner high density polyethylene (HDPE) liner, upper cap assembly, winded composite layer and composite center hoop, which are designed in 3-D modeling software and then finite element analysis is performed on them. After number of analysis, the material properties are suggested as E-glass/Vinylester from 70° to 20° fiber angle from upper to lower side. The helical part of cylinder has a layer of E-glass/Vinylester 15° and an extra layer of hoop part with E-glass/Vinylester 90°. The von mises criteria predicts that the weakest point of structure lies in the compostie hoop, so it is recommended to make this part strengthen as much as possible.
Paper : Study of Al2O3/ZrO2 (5 nm/20nm) Nanolaminate Composite
( G Balakrishnan ),( A Wasy ),( Ha Sun Ho ),( P Sudhakara ),( S I Bae ),( J I Song ) 한국복합재료학회 2013 Composites research Vol.26 No.1
A nanolaminate consisting of alternate layers of aluminium oxide (Al2O3) (5 nm) and zirconium oxide (ZrO2) (20 nm) was deposited at an optimized oxygen partial pressure of 3×10-2 mbar by pulsed laser deposition. The nanolaminate film was analysed using high temperature X-ray diffraction (HTXRD) to study phase transition and thermal expansion behaviour. The surface morphology was investigated using field emission scanning electron microscopy (FE-SEM). High temperature X-ray diffraction indicated the crystallization temperature of tetragonal zirconia in the Al2O3/ZrO2 multilayer -film was 873 K. The mean linear thermal expansion coefficient of tetragonal ZrO2 was 4.7×10-6 K-1 along a axis, while it was 13.68×10-6 K-1 along c axis in the temperature range 873-1373 K. The alumina was in amorphous nature. The FESEM studies showed the formation of uniform crystallites of zirconia with dense surface.
Fracture Toughness of Plasma Coated Zirconia(ZrO₂)
Cheon won,Atta Ur Rehman,Abdul Wasy,Dong-woo Lee,Sun-ho Ha,Jung-Il Song 대한기계학회 2012 대한기계학회 춘추학술대회 Vol.2012 No.11
Zirconia (ZrO₂) is a ceramic material having good mechanical characteristics for industrial applications. This work is an extension of previous work in which the friction coefficient and wear resistance of diamond-like carbon (DLC) films were evaluated. DLC films had attracted more interest due to their excellent physical and chemical properties, such as very high elastic modulus, high electric resistivity, high dielectric constant, high wear resistance, low friction coefficient, bio compatibility, chemically inert and thermally stable. The objective of the present study was to fabricate DLC thin film coatings on ZrO₂ alloy surface using Plasma Enhanced Chemical Vapor Deposition (PECVD) method and evaluation of Vickers hardness. This work is focused due to high demand of DLC coated ceramic materials and it was concluded that, DLC coatings helps to improve the Vickers hardness of ceramics.
Static, Harmonic and Fatigue Analysis of a Casing Oscillator
Atta ur Rehman Shah(샤아따울레만),Addul Wasy Zia(압둘와지지아),Kim Chang Uk(김창욱),Song Jung-il(송정일) 대한기계학회 2013 대한기계학회 춘추학술대회 Vol.2013 No.5
Casing oscillators are used to extract rocks and soil from depth of the earth during foundation work of buildings, bridges and drilling operations. Hydraulic piston cylinders are used in this equipment to produce torque for shaking of the pipe inside the drill hole. Due to the consistent torque loadings the oscillator is always under a vibrating load of known frequency. Hence there occurs fatigue failure in some parts of the machinery. This study is a finite element analysis of an existing design of the casing oscillator under the operating conditions. Static, harmonic and fatigue analyses are performed under real loadings. Critical areas of the design and fatigue life of the components are predicted.
하선호(Sung-Ho Ha),이동우(Dong-Woo Lee),압둘 와지 지아(Abdul Wasy Zia),송정일(Jung-Il Song) 대한기계학회 2013 대한기계학회 춘추학술대회 Vol.2013 No.5
Ball Valves are being used as a key element in the process industries. The industrial development of valves has increased steadily and it requires high design reliability with long service life. Currently, the development of a high performance valves is not easy because of the lack of technology in Korea. Valves are being imported up to 58 percent of domestic market having worth of almost 7 million US dollars. Therefore, in this work, improvement of the design and performance of industrial valves gad studied to achieve longer service life and best output during operation. The structural stability was evaluated using ANSYS FSI(Fluid-Structural Interaction) module. Moreover, torque analysis simulation was performed to compare software and experimental results to obtain maximum product reliability. This simulation results were used to predict the change in torque by change in shape, thereby, reducing the time and cost of manufacturing number of protypes for experimental validation.