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

• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 2003.11a
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• pp.193-200
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• 2003

In this study a general Galerkin FE formulation of the incompressible Reynolds equation is derived for lubrication analyses of noncontacting mechanical face seals. Then, the formulation is applied to analyze the flexibly mounted stator-type reactor coolant pump seals of local nuclear power plants, which have deep straight grooves or plane coning on their primary seal ring faces. Their various lubrication performances have been predicted. Results show that the analyzed deep straight groove seal should have a net coning of less than $0.6\;{\mu}m$ to satisfy the leakage limit. And for the same amount of equilibrium opening force the plane coning seal requires to have a 3 times higher dimensionless coning than the deep straight groove seal.

• Tribology and Lubricants
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• v.21 no.5
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• pp.201-208
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• 2005

This paper presents the FEM analysis on the contact behavior characteristics of mechanical face seals in a small hydro-power turbine. Especially, the axial displacement and contact normal stress between a seal ring and a seal seat of a primary sealing unit have been analyzed as functions of rotating speed of a hydro-turbine, sealing gap, water and cooling fluid temperature. Those are strongly related to a leakage of water and wear between a seal ring and a seal seat. The FEM computed results present that the rotating speed of a hydro-turbine may be kept less than 800 rpm, and the sealing gap in a primary sealing unit is restricted $0.5\~5$. The coolant temperature in which is most influential parameter to the contact behaviors of a sealing unit may be kept less than $15^{\circ}C$ for a safe operation of a sealing unit without a leakage and wear.

• Tribology and Lubricants
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• v.5 no.2
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• pp.48-54
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• 1989

The effects of angular misalignment, coning and the temperature difference between the primary seal ring and the seal seat on the pressure distribution in mechanical face seals are analyzed. The modified Reynolds equation for the temperature dependent viscosity was solved by a finite difference approximation and Gauss-Seidel method. It is shown that the amplitude of pressure is significantly affected by the misalignment of the seals and a large temperature difference between the rotor and the stator.

• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 1987.06a
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• pp.50-56
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• 1987

A mechanical face seal is most commonly used to seal liquids and gases at various speeds, pressures and temperatures. The primary seal ring is in sliding contact with the seal seat and as a result heat in the vicinity of the interface is generated. Local temperatures at points along the circumferential direction will fluctuate as asperities on the surfaces pass. This kind of fluctuation of temperature has been investigated to take place. This may lead to the hot spots phenomenon between the contacting asperities. Sibley and Allen showed photographic evidence of systemically moving hot spots in the contact zone. The appearance of such a temperature disturbance has been attributed to a kind of thermoelastic instabilities between two surfaces: This involves a feedback loop which comprises localized elevation of frictional heating, resultant localized thermal bulding, localized pressure increase as the result of the bulging and futher elevation of frictional heating as the result of the pressure increase. The heating of hot spots will be continued until the expanded material due to the frictional heating is worn off. Therefore to predict the speed of temperature propagation into the body is essential to the analysis of heat transfer on the edge of the seal.

• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 2001.11a
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• pp.204-211
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• 2001

For the treatment of high compressibility number in the Reynolds equation, a new class of exponential high-order shape functions has been recently introduced in the literatures. In this paper a FE lubrication analysis method of high speed gas mechanical face seals is developed, implementing these shape functions. Their validity and usefulness are presented using 1-D gas bearing models. And a validation of developed 2-D analysis code is shown with a gas flat and spiral groove face seal models.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.15 no.4
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• pp.118-124
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• 2016

In this paper, the model to develop the forming process for turbine seal is suggested. And numerical approach for the shape design of the turbine seal is examined. Because of the thin thickness of the turbine seal, the seal is easily fractured in the manufacturing process. The main factors of the seal manufacturing consist of addendum angle and dedendum angle, fillet on the addendum face, number of the gear teeth, sheet initial location and gear initial location, rake and vertical clearance. The structure and shape of seal are modeled using the commercial 3D mechanical design program, CATIA(V5/R20). Also, rolling process to manufacture the turbine seal is analyzed using DEFORM$^{TM}$-3D(V11), commercial forming analysis software and runs under PC workstation. This study focused on the shape design of turbine seal. Through this research, the main factors to make the turbine seal for airplane turbine engine can be obtained. This study results are reflected to the shape design for turbine seal.

• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 1989.06b
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• pp.35-47
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• 1989

누설방지를 목적으로 산업용 기계에서 많이 사용되고 있는 기계평면시일(mechanical face seal)은 기능상 높은 신뢰도를 요구하고 있다. 이를 위하여 동적 안정성이 커야되고, 밀봉된 유체의 누설을 최소화시킬 수 있는 정도에서 시일의 수명을 결정해야 한다. 이와같이 상반된 성질을 동시에 만족시키기 위하여 시일 성능에 영향을 미칠 수 있는 기하학적 요인들을 고려하여 해석해야 한다. 일반적으로 미끄럼 접촉운동을 하고 있는 시일에서 시일링 간극(sealing gap)이 수 micron 단위라는 점을 고려할때 시일 조립시 중심맞추기(alignnment) 정미\ulcorner 결여 및 회전축의 자중량 등에 의한 기계적 변형(mechanical distortion), 특히 고온의 분위기에서 작동되고 있는 시일의 열변형(thermal distortion)은 시일의 경사집에 커다란 영햐을 주고 있다. 또한 누설을 최소화시킬 목적으로 시일 링(seal ring) 을 시일의 경사짐에 커다란 영향을 주고 있는 스프링의 강성도를 증가시키면 상대 미끄럼 운동을 하고 있는 접촉명이 건조마찰에 의한 마멸이 진행되어 코닝(coning)현상이 생긴다. 시일 평면에서 코닝 현상은 시일의 축방향 분리력(axial separtating force)과 경사 모우면트(tilting moment)에 커다란 영향을 주고 있는 것으로 알여졌다. 이들의 연구는 주로 경사진 시일평판에 시일근사치이논(seal approximation bhoryl)을 이용하여 1차원 비압축성에 관한 시월 성능을 해석하였다. 본 연구에서는 비압축성 유체의 점성이 온도에 의하여 변화를 일으키는 조건하에서 경사진 회전시일에 코닝이 발생되었을때 시일링 각극에서의 압력분포를 ㅈ차원인 경우에 대하여 수치적으로 해석을 하였다.

• Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
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• 2003.10a
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• pp.41-46
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• 2003

In this paper, two different methods are developed to be used for the design of noncontact dry gas seal which is used to prevent gas leakage of high speed rotating shaft-housing machineries. First method is using FEA to compute the deformation of seal face and the other is using Influence Coefficient Method in order to save computation of FEA. In both cases, heat load and mechanical loads are applied such as heat generation, bulk temperature and nodal force, bulk pressure, centrifugal force, respectively. ICM method is verified correct and effective and both methods give reliable and useful deformation results for the design of mechanical seals.

• Transactions of the Korean Society of Mechanical Engineers
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• v.16 no.12
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• pp.2261-2267
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• 1992

The equations are derived for the evaluation of the axial contact force. The contact forces for rubber seals are analyzed as a function of the ratio of real contact length, the thickness of seal lip, the inclined angle of seal lip, and the interference between the edge of seal lip and the rotating inner ring. The design data for rubber seals are presented in terms of the ratio of real contact length, initial inclined lip angle, lip thickness and the interference. The calculated results show that the deflected interference and the circumferential stress cause considerable change of contcat forces for the low sealed pressure.