Stress concentration factors due to axial loading of axisymmetric external projections on hollow tubes

Abstract

The finite element method has here been used to determine stress concentration factors due to axial loading applied to axisymmetric, external projections on hollow tubes. A range of tube and projection dimensions have been covered by the investigation. There is good agreement between the present results and previously published data. The results are presented in a manner which allows stress concentration factors to be quickly determined, for any shape within the range covered by the investigation.

Stress concentration factor and minimum hub length predictions for hollow tubes with internal and external flanges subjected to axial loading

“…A comparison between the finite element results in previously published papers [2,4] and predictions obtained in this study confirm the accuracy of the finite element meshes used here, which are, in any case, based on previous meshes (see, for example, reference [2]). Values for Young's modulus and Poisson's ratio of 200 GPa and 0.3 respectively are used throughout.…”

“…The finite element elastic stress concentration factors obtained in previous studies [2,4] have been used to obtain useful prediction equations, based on a statistical multiple non-linear regression method [11], covering the extensive range of geometries listed in Table 2. Although similar equations have been presented in the past for internal flanges [12], these new equations are more accurate and also cover external flanges:…”

“…Elastic stress concentration factors due to axial loading of axisymmetric external projections have been presented in reference [2] for an extensive range of component geometries. Similarly, elastic stress concentration factor data for axial loading of axisymmetric internal projections are also available in reference [3].…”

“…In the present study, relationships between these two parameters, in a form suitable for design calculations, have been developed, in order to eliminate the need for complex numerical or analytical calculations associated with hub length. Elastic stress concentration factors due to axial loading of axisymmetric external projections have been presented in reference [2] for an extensive range of component geometries. Similarly, elastic stress concentration factor data for axial loading of axisymmetric internal projections are also available in reference [3].…”

“…uniform pressure applied to the inside surface and outside surface of tube wall, for internal/external flanges respectively r fillet radius r ic inside radius of tube R 2 multiple coefficient of determination t tube wall thickness T projection thickness w radial width of projection W applied load factor used in attenuation length hub length " r radial strain " hoop strain angle used to define the position of strain gauges pressure ratio ¼ P b =P a Poisson's ratio a mean axial stress in the tube aeq mean axial equivalent stress in the tube eq equivalent stress m meridional (surface) stresŝ eq maximum equivalent stress (in the fillet region) m maximum meridional stress (in the fillet region)…”