604 Finite Element Stress Analysis and Sealing Performance Evaluating of Pipe Flange Connection Subjected to External Bending Moment and Internal Pressure

In practice, PTFE tape is being used for sealing of a pipe fitting. However, the efficiency, the decrease in work time, and the sealing performance can be improved by using adhesive instead of the tape. When such a pipe fitting is under an internal pressure and external bending moment by an internal fluid and others, however, an influence in the sealing performance is taken by how to use an adhesion. This study deals with the stress analysis and the evaluation of the sealing performance of the pipe fitting with an adhesive under an internal pressure and an external bending moment analyzed by using the 3-dimensional elastic finite element method. Furthermore, the experiment of the leakage test of the pipe fitting with an adhesive was carried out when the above loads were applied to the pipe fitting. From 3-D FEM analysis, the following results were obtained: (1) the stress distribution at the interface between thread and adhesive on the side of the internal pressure is tensile stress, and stress on the opposite side is compressive, (2) the stresses at the area of the clearance between the valley of the screw and the mountain increase as the numbers of turns of the thread in fittings increase, and (3) the compressive stress at the side of the tensile part in the fittings decrease as the external bending moments increase. However, the sealing performance will not change when the bending moment is not so great because the compressive stress at the side of the compressive part in the fitting increases. From the leakage tests, the following results of the sealing performance were obtained: (1) the sealing performance of a fittings with adhesive under an internal pressure and a bending moment didn’t decrease when bending moment was not so great, and (2) when it exceeds fixed pressure, rapid leakage from the fitting with adhesive occurred by the exfoliation of the adhesive. Furthermore, the numerical results are in fairly good agreement with the experimental results.

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FEM Stress Analysis and Sealing Performance in Non-Circular Flange Connections With Gaskets Subjected to Internal Pressure

Design Engineering, Volumes 1 and 2 ◽

10.1115/imece2003-42286 ◽

2003 ◽

Author(s):

Toshiyuki Sawa ◽

Wataru Maezaki

Keyword(s):

Finite Element Method ◽

Finite Element ◽

Internal Pressure ◽

Stress Analysis ◽

Stress Distributions ◽

Flange Connection ◽

Bolt Preload ◽

Sealing Performance ◽

Element Method

The contact gasket stress distributions of a non-circular flange connection with a compressed asbestos sheet gasket subjected to internal pressure were analyzed taking account a hysteresis of the gasket by using finite element method (FEM). Leakage tests were also conducted using an actual non-circular flange connection with a compressed asbestos sheet gasket under internal pressure. By using the contact gasket stress distributions and the results of the leakage tests, the new gasket constants were calculated. A difference in the new gasket constants between the values obtained from the present study and those by the PVRC procedure was substantial. In addition, a method to determine the initial clamping bolt force (bolt preload) for a given tightness parameter was demonstrated. abstract text here.

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FEM Stress Analysis and an Evaluation of the Sealing Performance in Non-Circular Flange Connections With Gaskets Subjected to Internal Pressure

Volume 2: Computer Technology ◽

10.1115/pvp2006-icpvt-11-93266 ◽

2006 ◽

Author(s):

Toshiyuki Sawa ◽

Ryo Kurosawa ◽

Wataru Maezaki

Keyword(s):

Finite Element Method ◽

Finite Element ◽

Internal Pressure ◽

Stress Analysis ◽

Stress Distributions ◽

The Finite Element Method ◽

Flange Connection ◽

Bolt Preload ◽

Sealing Performance ◽

The Difference

The contact gasket stress distributions of a non-circular flange connection with a compressed sheet gasket subjected to internal pressure were analyzed taking into account of the hysteresis behavior of the gasket by using the finite element method (FEM). Leakage tests were also conducted using an actual non-circular flange connection with a compressed sheet gasket under internal pressure. Using the contact gasket stress distributions and the results of the leakage tests, the new gasket constants were calculated. The difference in the new gasket constants between the values obtained from the present study and those by the PVRC procedure was substantial. In addition, a method to determine the initial clamping bolt force (bolt preload) for a given tightness parameter was demonstrated.

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Finite-Element Stress Analysis and Strength Evaluation of Super High Pressure Mercury Lamp Bulbs under Internal Pressure

Journal of Light & Visual Environment ◽

10.2150/jlve.29.11 ◽

2005 ◽

Vol 29 (1) ◽

pp. 11-18

Author(s):

Masahiko KASE ◽

Yuichiro IWAMA ◽

Toshiyuki SAWA

Keyword(s):

Finite Element ◽

High Pressure ◽

Internal Pressure ◽

Stress Analysis ◽

Mercury Lamp ◽

Strength Evaluation ◽

Finite Element Stress Analysis ◽

Finite Element Stress

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Stress Analysis of Tire Sections

Tire Science and Technology ◽

10.2346/1.2137527 ◽

1996 ◽

Vol 24 (4) ◽

pp. 349-366 ◽

Cited By ~ 4

Author(s):

T-M. Wang ◽

I. M. Daniel ◽

K. Huang

Keyword(s):

Finite Element ◽

Internal Pressure ◽

Stress Analysis ◽

Strain Analysis ◽

Experimental Stress ◽

Inflation Pressure ◽

Substantial Agreement ◽

Finite Element Stress Analysis ◽

Strain Components ◽

Fringe Patterns

Abstract An experimental stress-strain analysis by means of the Moiré method was conducted in the area of the tread and belt regions of tire sections. A special loading fixture was designed to support the tire section and load it in a manner simulating service loading and allowing for Moiré measurements. The specimen was loaded by imposing a uniform fixed deflection on the tread surface and increasing the internal pressure in steps. Moiré fringe patterns were recorded and analyzed to obtain strain components at various locations of interest. Maximum strains in the range of 1–7% were determined for an effective inflation pressure of 690 kPa (100 psi). These results were in substantial agreement with results obtained by a finite element stress analysis.

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