Influence of the Wall Thickness on the Allowable and Failure Pressures of Two- and Tree-Way Globe Valve Bodies

Abstract

A globe valve is a linear motion valve used to shut off and regulate fluid flow in pipelines. Depending on the number of process connections, they are produced as two‑ or three-way valves. The main valve component carrying the internal pressure is the valve body. For safe exploitation, the valves are designed with the allowable internal pressure taken into consideration. The aim of this paper is to investigate the influence of the wall thickness on the allowable and failure pressures of two- and tree-way globe valve bodies, DN50 and DN100 respectively. Twice-elastic-slope (TES) and the tangent‑intersection (TI) methods are used to obtain the plastic collapse pressures at the critical location which was determined (Fig. 1a and 1b) at the location where maximum equivalent plastic strain throughout the valve body thickness reaches the outer surface. Obtained values are used afterwards to calculate corresponding allowable pressures according to the limit design method, while the failure pressure at the same location was determined as the highest point from the load-maximal principal strain curve. Calculated allowable pressure values, for both valve bodies, are compared with the corresponding ones obtained using the EN standard.

Sustainable development of pressure equipment using 3D Digital Image Correlation method

“…Considering symmetry of the model and loadings subjected to valve internal structure, one half of the model is analysed. Boundary conditions [33] include restraining displacement in symmetrical plane in transversal direction [12]. Furthermore, valve model is simply supported by two nodes at model edges (Fig.…”

“…Nozzle stress results were presented later by Rodabaugh et al [8] but clarification of the stresses in the vicinity of this geometrical continuity continue to be of interest. Other authors also analysed sphere/cylinder junction in their papers [9][10][11][12][13][14] To improve understanding of local conditions in loaded, complex structures, the optical three-dimensional digital image correlation method (DIC) is used in these investigations. DIC methods [15] are non-contacting and can be used for 2D (2D-DIC) and 3D (3D-DIC or StereoDIC) [16] surface displacement and strain measurement (e.g.…”