Tightness analysis method for flange connection of pipes with metal Z-shape seal during the influence of external axial force

Introduction. Today thin-walled structures are widely used in the construction industry. The analysis of their rigidity, strength and stability is a relevant task which is of particular practical interest. The article addresses a method for the numerical analysis of stability of an axially-compressed i-beam rod subjected to the axial force and the bimoment. An axially compressed i-beam rod is the subject of the study. Materials and methods. Femap with NX Nastran were chosen as the analysis toolkit. Axially compressed cantilever steel rods having i-beam profiles and different flexibility values were analyzed under the action of the bimoment. The steel class is C245. Analytical data were applied within the framework of the Euler method and the standard method of analysis pursuant to Construction Regulations 16.13330 to determine the numerical analysis method. Results. The results of numerical calculations are presented in geometrically and physically nonlinear settings. The results of numerical calculations of thin-walled open-section rods, exposed to the axial force and the bimoment, are compared with the results of analytical calculations. Conclusions. Given the results of numerical calculations, obtained in geometrically and physically nonlinear settings, recommendations for the choice of a variable density FEM model are provided. The convergence of results is estimated for different diagrams describing the steel behavior. The bearing capacity of compressed cantilever rods, exposed to the bimoment, is estimated for the studied flexibility values beyond the elastic limit. A simplified diagram, describing the steel behaviour pursuant to Construction regulations 16.13330, governing the design of steel structures, is recommended to ensure the due regard for the elastoplastic behaviour of steel. The numerical analysis method, developed for axially-compressed rods, is to be applied to axially-compressed thin-walled open-section rods. National Research Moscow State University is planning to conduct a series of experiments to test the behaviour of axially-compressed i-beams exposed to the bimoment and the axial force. Cantilever i-beams 10B1 will be used in experimental testing.

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ELASTO-PLASTIC ANALYSIS METHOD FOR FRAME WITH EXPOSED-TYPE COLUMN BASE CONSIDERING INFLUENCE OF VARIABLE AXIAL FORCE

Journal of Structural and Construction Engineering (Transactions of AIJ) ◽

10.3130/aijs.68.127_3 ◽

2003 ◽

Vol 68 (571) ◽

pp. 127-135 ◽

Cited By ~ 6

Author(s):

Hiroyuki TAMAI

Keyword(s):

Axial Force ◽

Analysis Method ◽

Plastic Analysis ◽

Column Base

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The Thermal Expansion Analysis for Submarine Pipe-in-Pipe Based on Shear Lag Theory

Volume 5A: Pipeline and Riser Technology ◽

10.1115/omae2015-41031 ◽

2015 ◽

Author(s):

Xiaoxia Liu ◽

Xu Jia ◽

Lusheng Jia ◽

Kankan Ni

Keyword(s):

Thermal Expansion ◽

Axial Force ◽

Force Distribution ◽

Analysis Method ◽

Submarine Pipeline ◽

Shear Lag ◽

Pipeline Design ◽

Shear Lag Theory

The thermal expansion analysis is important in submarine pipeline design and research. A new thermal expansion analysis method of submarine pipe-in-pipe is proposed in this paper based on the shear lag theory. The axial force distribution and the thermal expansion displacement of submarine pipe-in-pipe can be calculated by this method. The analysis method is simple and convenient but with detailed results. It can be used for the thermal expansion analysis of submarine pipe-in-pipe.

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Nonlinear Response of U-Tubes to a Differential Axial Movement Between Two Legs

Journal of Pressure Vessel Technology ◽

10.1115/1.3264897 ◽

1987 ◽

Vol 109 (2) ◽

pp. 205-211 ◽

Cited By ~ 1

Author(s):

N. V. Leˆ

Keyword(s):

Axial Force ◽

Nonlinear Response ◽

Thermal Loading ◽

Maximum Stress ◽

Nonlinear Behavior ◽

Linear Analysis ◽

Analysis Method ◽

Nonlinear Functions ◽

Linear Elastic ◽

Differential Thermal Expansion

The deflections and the stresses in U-tubes due to differential thermal expansion between two legs are nonlinear functions of the thermal loading even with linear elastic materials. The nonlinear behavior is due to the fact that the induced axial force in U-tubes, tension in cold leg and compression in hot leg, have some effects on the deflection of the tubes. In the present work, the nonlinear analysis method is fully described and applied. Numerical results are shown in comparison with those given by simplified linear analysis in which the effects of axial force on deflections of tubes are neglected. In general, the effects of the nonlinear behavior are negligible for the maximum stress; however, they may be significant for some secondary details such as the tube rotation and the stress at apex of the tube. The present work is intended to justify the validity of some earlier formulas, developed by the author in a previous work, for calculation of secondary stresses in heat exchanger U-tubes.

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