• Transactions of the Korean Society of Mechanical Engineers
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• v.18 no.6
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• pp.1559-1566
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• 1994

Using the finite element method, the contact force, contact band width and temperature distribution of lip seals analyzed for the interference including some nonlinearities such as material nonlinearity, geometrical nonlinearity and nonlinear contact boundary condition. The calculated results showed that the contact stress concentrated on the contact zone between the garter spring and the rubber toward the flex side, the contact edge of lip seals. The high contact forces due to the increased interference separate the sealing gap between the lip edge and the rotating shaft. This may lead to leak the sealed oil.

• Transactions on Electrical and Electronic Materials
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• v.9 no.1
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• pp.33-37
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• 2008

This paper describes the development of a new $5.0{\times}3.2mm$ SAW filter bank which is consist of 12 L, C matching components and 4 SAW bare chips on PCB substrate with CSP technology. We improved the manufacturing cost by removing the ceramic package through direct flip bonding of $LiTaO_3$ SAW bare chip on PCB board after mounting L, C passive element on PCB board. After that we realized the hermitic sealing by laminating the epoxy film. To confirm the confidentiality and durability of the above method, we have obtained the optimum flip bonding & film laminating condition, and figured out material property and structure to secure the durability & moisture proof of PCB board. The newly developed super mini $5.0{\times}3.2mm$ filter bank shows the superior features than those of existing products in confidence, electrical, mechanical characters.

• Proceedings of the KSME Conference
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• 2001.06a
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• pp.860-864
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• 2001

Today's industrialized plants are required to reduce SOx emitted from stacks at factories, utility power stations, etc. For this purpose, flue gas desulfurization (FGD) system is installed and gas-gas heater (GGH) is used to play a vital role to reheat the wet treated gas from FGD. The sector plates are located at cold and hot sides of gas gas heater. They serve as sealing to prevent mixing treated and untreated gases. Therefore, the deformation of the sector plate due to its dead weight and gas pressure should be considered as major factor for the sector plate design.

• Journal of the Korean Society for Precision Engineering
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• v.16 no.4 s.97
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• pp.122-128
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• 1999

Bolted joint assembly for nuclear power plants consists of various components : cover plate, retainer plate, manway flange, gasket and stud bolts/nuts. To guarantee the soundness of the joint, it is important to prevent leakage through the gasket and reduce the stress concentration factor at the thread root. In this paper, Submodeling technique for the finite element method is proposed to accurately compute three dimensional contact stresses which govern the sealing performance and the maximum contact stresses at the threads root. For verification of global solutions used as boundary conditions of submodel solution, the stresses on the cover plate and the manway flange are measured by strain gages when internal pressure is applied to the bolted joint assembly. The numerical results are compared with the experimental results.

• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 2003.11a
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• pp.335-340
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• 2003

This paper presents contact behavior of a perfluoroelastomer bonded door seal by a non-linear finite element method using the mechanical and thermal analysis. The shape effects are investigated for sealing performance of bonded door seal. Also maximum stress, temperature distribution and contact force are investigated. A bonded door seal was modeled three shape. The highest contact force occurs at model III(sunflower shape). The maximum stress of model III is lower than that of the others. The calculated FEM results show that the model III has excellent performance compared with other seal models.

• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 2003.11a
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• pp.241-247
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• 2003

The sealing performance of O-ring is effected in environments of the O-ring seal, like that applied pressure, working temperature, pre-compressed ratio and materials. In this paper, design of composite O-ring under pressurized, compressed was optimized based on Taguchi experimental design method. and it analysed numerically using non-linear finite element method. Ogden model in which is developed based on the experimental data is used for simulating the contact stress and strain in NBR and PTFE materials. Sensitivity analysis was performed with FEM results, which are contact stress, strain and temperature as variable.

• Tribology and Lubricants
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• v.15 no.4
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• pp.297-303
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• 1999

O-rings in automotive engines are important components such as a coolant pipe, engine oil circulating lines and fuel injector for sealing that makes efficient performance of the engine. Life cycle of O-rings is effected in environments of the O-ring seal, like that applied pressure, working temperature, precompressed ratio and materials. It is related in extrusion, expansion and fatigue failure of O-rings. In this paper, an pressurized, compressed elastomeric O-ring inserted into a rectangular groove is analysed numerically using the nonlinear finite element method. The calculated FEM results showed that extrusion ratio and contact stress are strongly related to the gap clearance and edge radius of the groove.

• Transactions of the Korean Society of Pressure Vessels and Piping
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• v.13 no.2
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• pp.44-50
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• 2017

The shaft seal of the reactor coolant pump is installed on the upper side of the rotating shaft of the pump to seal the reactor coolant from flowing out between the rotating shaft and the non-rotating parts. In this study, the loading conditions for the normal operation and faulted conditions are identified and structural integrity evaluation is performed using the finite element stress analysis for the sealing apparatus of the APR 1400 reactor coolant pump. It is confirmed that the stress analysis results satisfy the design criteria at all loading conditions.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2009.05a
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• pp.220-223
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• 2009

Metallic bipolar plate for molten carbonate fuel cell(MCFC) is composed of the shielded slot plate and the center plate. Among these, the center plate plays an important role in gas sealing. Therefore, manufacturing of the center plate is considered one of the key issues in MCFC. The center plate is manufactured by bending process. In bending process, springback and recoiling are two main problems. By using the modified punch shape with 'step', springback and recoil are reduced. The aim of this article is to find the effect of modified punch shape. So, the bending stress along thickness direction and material direction were investigated using FEM.

• Elastomers and Composites
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• v.50 no.4
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• pp.251-257
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• 2015

The rubber seal is a part inserted into servo cylinder to keep the air pressure constant. In order for efficient movements of the servo cylinder, the frictional coefficient of the rubber seal needs to be minimized while the sealing is maintained. In this work the friction characteristics of rubber seal specimen are tested on metal plate at various conditions. The experimental conditions include roughness level, applied pressure, lubrication, and rubbing speed. The design of experiment approach is taken to assess the effect of each parameter. The nonlinear frictional response of the rubber is applied to the FEM model simulating the servo cylinder movement. The result demonstrates that precise optimization of the servo cylinder movement must be preceded by preliminary experiments coupled with the theory and FEM model.