Various resources have long been available from which bolted flange connection (BFC) preload guidance can be chosen. These range from Rules of Thumb gleaned from experience, to tables and charts based on average gasket stress, to parametric generalizations derived from the results of limited finite element analyses. Because the primary components of a BFC (flange, fastener and gasket) interact with one another to respond as a single system, and the system is unique to the conditions that define it, guidance based on these specific conditions will improve the accuracy of preload solutions and generate data to show the relative strengths and weaknesses of a given BFC. This paper presents a methodology that sets practical stress limits on a collection of commonly used ASME B16.5 welding neck flange components and then uses finite element analysis to solve the condition of preload that results in one or more limits being satisfied. Each preload solution is unique to the properties and geometries that define it and includes the effects of three design conditions. Fastener stress solutions include both the tension and bending components. This shows that yielding can initiate at relatively low values of preload when flange rotation is significant. Charts are created to show solution trends. This simplifies the task of identifying the component that sets the upper bound for a given solution. It also provides the basis to compare similar component combinations.
- Pressure Vessels and Piping
Fastener Preload Guidance Methodology for ASME B16.5 Welding Neck Flanges
Wacker, R. "Fastener Preload Guidance Methodology for ASME B16.5 Welding Neck Flanges." Proceedings of the ASME 2008 Pressure Vessels and Piping Conference. Volume 2: Computer Applications/Technology and Bolted Joints. Chicago, Illinois, USA. July 27–31, 2008. pp. 171-179. ASME. https://doi.org/10.1115/PVP2008-61410
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