Stress analysis of bolted flange joints with different shell connections

Abstract

Pressure vessel piping components are widely utilized in a variety of industries, including oil and gas, as well as nuclear power and power plants. Due to the high-pressure and hightemperature conditions, the most critical issue concerning their applications is operational safety. Different shells are joined permanently by welded joints or temporarily by bolted flange connections, also known as bolted flange joints, in pressure vessels and piping systems. A critical task in the design process is to determine the stress concentration level at the point where the shell meets the flange ring. One of the most challenging tasks is the determination of the flange integrity of this junction. In the design process, it is beneficial to employ analytical and finite element techniques to model the general behavior of the bolted flange joint under various loading conditions. The results generated from the analytical solution will be validated by the finite element technique. Furthermore, the performance of various flange connection configurations is not comprehended well. However, the present ASME BPV Code flange design does not incorporate the leakage criteria or flexibility analysis to provide an accurate assessment of various parameters. The purpose of this research is to assess the integrity and leakage tightness of various types of shells connected to the flange ring. This investigation examines various parameters such as flange rotation, gasket contact stress, and stress distribution at the flange-shell junction using multiple shell theories depending on the form and geometry. Several forms of shell connections have been compared together including cylindrical, spherical, dished, and conical. All shells are directly connected to a raised-face flange ring without a hub. Furthermore, the shell connections have been simulated using a general purpose finite element software to support the analytical method and validate the study. Another significant purpose of this study is to look into the influence of flange dimensions on the results by examining various sizes of flange connections. For this purpose, three different sizes of the flange, namely NPS 26, 48, and 60 ASME B16.47 series A, were modeled and simulated by the ANSYS software to make comparison between numerical and analytical results. It is worth noting that the numerical and analytical results compared well.

Date	17 Aug 2022
Original language	American English
Awarding Institution	École de technologie supérieure
Supervisor	Hakim A. Bouzid (Supervisor)