• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
• /
• 1998.04a
• /
• pp.149-158
• /
• 1998

The thermal deformation of the contact seal components has been analyzed using the finite element method. The temperature distributions, the thermal deformations and contact stresses are solved numerically for the contact surface with wear coning effects. The thermal deformation is always shown to distort the sealing surface along the radius of the seal ring. The results show that the deformations of inner radius side are significant compared with those of outer radius. Thus, the thermal deformation due to thermal heatings may promote the coned face wear or wear related thermal cracks at the contacting face of the seal ring component.

• Journal of the Korean Society of Propulsion Engineers
• /
• v.4 no.3
• /
• pp.64-73
• /
• 2000

The joint parts was composed of inner AL(aluminum) ring, FRP wedge and motor case which was manufactured by filament wound method. Where the motor case consists of helical and hoop layer. The finite element analysis was performed for the design variable of joint parts to improve the performance of motor case. Where the adhesive layer was modeled to elasto-perfect plastic material and the contact condition of AL ring and wedge was modeled by using the contact surface element of ABAQUS. And the sliding distance of AL ring and the hoop strain of composite case were compared to hydro-static test results to verify the accuracy of analysis results. When wedge and AL ring was perfect bonding, though the hoop strain of joint part was reduced, the maximum shear stress was occurred at the adhesive layer. Thus the adhesive layer had failed due to the high shear stress before the failure was occurred at the case. And as another design method, when wedge and AL ring was contact condition, the shear stress on adhesive layer was decreased. But the hoop stress of joint part increased due to the sliding behavior of AL ring. Finally, the fail was occurred at the composite case of joint part. The improved joint method reinforced by hoop layer to the joint parts under contact condition for wedge and Al. ring reduced the joint part's hoop strain by constraint the sliding behavior of AL ring.

• Proceedings of the Korean Society of Propulsion Engineers Conference
• /
• 2006.11a
• /
• pp.25-29
• /
• 2006

The object of this study is to develop new examination techniques for measuring the O-ring deformation behavior under the pressure condition. The extrusion lengths measured from the computed tomography were in good agreement with the results that measured from non-contact laser displacement sensor. The deformed shapes of O-ring measured by the computed tomography and evaluated by the FEM agreed well with the extrusion length and the expanded diameter. But the contact widths of the O-ring and steel measured by the computed tomography were a little larger than the results of the FEM.

• Journal of the Korean Society of Manufacturing Process Engineers
• /
• v.17 no.1
• /
• pp.34-41
• /
• 2018

A flange joint is a pipe connection used to prevent the leakage of high-pressure fluids by inserting a gasket and tightening the bolts. Among several kinds of gaskets available, metal ring type joint gaskets are most widely used in conditions that require high-temperature and high-pressure fluid flow, such as oil pipelines, gas pipes, pumps, valve joints, etc. The purpose of this study is to investigate the contact pressure and stress characteristics closely related to the sealing performance of Class 900 flange joints used in high temperature and high pressure environments. The dimensions of flange joints with five different nominal pipe sizes were determined with reference to those specified in ASME 16.5. The metal ring gaskets inserted in the joints were octagonal and oval gaskets. The bolt tensile forces calculated from the tightening torques were input as the bolt pretension loads in order to determine the contact pressure and stress levels after fastening. Loading was composed of three steps, including the fastening step, and different amounts of applied pressures were used in each analysis to investigate the effect of fluid pressure on the contact force of the joints. A general-purpose software, ANSYS 17.2, was used for the analysis.

• Korean Institute of Interior Design Journal
• /
• v.15 no.4 s.57
• /
• pp.106-114
• /
• 2006

The purposes of natural science museums are to educate the general public on the principles and application of science, and help them understand various aspects of science technology. Data should be analyzed by considering these educational aspects of exhibition, and the methods of presenting exhibits should be decided. Accordingly, the composition of exhibition contents with various exhibition elements has an important role at natural science museums. The relation and structure of exhibition themes are significant factors in helping visitors understand the principles of science and a system of viewing circulation can be used as an important tool for understanding the flow of exhibition. In other words, at the planning stage for the composition of exhibition contents, the relation of exhibition themes as well as the circulation patterns of viewers can induce active viewing behaviors. Therefore, centering on the patterns of viewing circulation as well as on the connectivity of exhibition themes at natural science museums, the purposes of this research are: 1) to conceptualize the composition of exhibition contents; and 2) to find elements that can induce active viewing behaviors by analyzing visitors' viewing behaviors. This research was establishing an analytical indicator of contact for viewing behaviors observed from the composition of exhibition scenarios, the active viewing patterns of engagement, first contact, and repeated contact were analyzed. First, a composition pattern with a high participation rate, in contact with exhibits, was found to induce an overall-viewing circulation and have a big ring of the composition of exhibition themes. Second, by inducing a partial-viewing circulation pattern, a high rate of first contacts was observed from a ring pattern of theme connection. Even for the structure with theme connection with depth, a high frequency of contacts with various exhibits was found when exhibition themes have a ring pattern. Third, the repeated contacts were mostly found in the form of scenarios, which has a successive structure of ring and cross patterns.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
• /
• 2006.05a
• /
• pp.1142-1148
• /
• 2006

The floating ring seal which is used in the high pressure turbo pump is frequently used in the oxidizer pump and the fuel pump of the turbo pump of the liquid propulsion rocket, because it is able to minimize clearance to decrease the leakage flow rate. But, floating ring seal has a tendency to increase the force which caused instability of system as the eccentricity ratio increases. In this paper, we devised design of floating ring seal which decrease contact area between floating and supporting ring. Modified floating ring seal has a tendency to decrease the eccentricity ratio compare with original floating ring seal. The whirl frequency ratio which is able to distinguish stability of system decrease compare with original floating ring seal

• Tribology and Lubricants
• /
• v.16 no.1
• /
• pp.33-38
• /
• 2000

Abstract- In this paper tribological characteristics of solid and liquid phase sintered W/C-35%Ni tappets were investigated. Three test methods were performed to investigate the wear and surface damage mechanism of sintered tappets. First, block-on-ring wear test was performed to investigate the wear characteristics under pure sliding condition. Second, simplified cam and tappet tests (called component wear test hereafter) were carried out to simulate the real contact history of cam and tappet. Also, after the test, contact surfaces were analyzed with scanning electron microscope to study the wear mechanism. As a final screening, engine dynamo tests were performed. Results showed that in the block on ring sliding wear test, solid phase sintered specimens showed superior wear resistance to liquid phase sintered specimens. The component wear tests and engine dynamo tests also showed the same results. Therefore, in these tests, solid phase sintered tappet material revealed superior wear resistant properties to liquid phase sintered one.

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2000.11a
• /
• pp.571-574
• /
• 2000

Seals in universal joint bearing are a important component reinforcing lubrication performance by holding a lubricant and preventing infiltration of dust, moisture, etc. There is a great difference in seal performance according to seal shape and bonding position. Therefore, in this study, as for the lib type seal and O-ring type seal, FEM analysis are conducted using Mooney-Rivlin Model. The results are indicate that O-ring having higher contact stress and larger contact area than lib type is more profitable.

• Proceedings of the KSME Conference
• /
• 2001.06a
• /
• pp.848-853
• /
• 2001

A study about the shrink fits of rotor and retaining ring in generator was performed for the cases of three radial interference. The shrink-fitted retaining ring used to restrain the end turns of the winded coils in the rotor against centrifugal force requires very careful attention during design and manufacture because it has traditionally been the highest-stressed component of the generator. The contact pressures and residual stresses were obtained by the finite element analysis for each radial interference at zero, 100% rated, and 120% rated speeds, respectively. The results of analysis show that the radial interference in use needs to be increased carefully.

• Journal of the Korean Society for Precision Engineering
• /
• v.16 no.6
• /
• pp.114-122
• /
• 1999

By using the FEM, a method for the stress analysis of the presented dies has been proposed. In this method, FEM and Lame equation are used for the analysis of the die insert and the stress ring, respectively. The proposed method includes the calculation of the contact pressure between the die insert and the stress ring. To show the validity, the proposed method has been applied to the simple test problem. The results of the stress analysis have been compared with the results of ANSYS, a commercial FE-code. Cold extrusion has been simulated by using the rigid-plastic FEM and the results of the deformation analysis have been used as the input of the die structure analysis. The stress states of the prestressed extrusion die have been obtained. The stress analysis of the die insert with stress rings has also been performed during extrusion.