Effect of Pad Thickness and Pad Diameter Variations on Plastic Limit Moment in Cylindrical Pressure Vessels Due to Nozzle Torsion Load

DOI

10.2991/978-94-6463-772-4_10How to use a DOI?

Keywords

Cylindrical pressure vessel; Plastic limit moment; Displacement limit; Torsional loading; ANSYS simulation

Abstract

During its operating life, pressure vessels can experience various types of internal and external loads, which cause stress concentration on the nozzles. One of the load types is torsional load, which occurs due to a combination of internal pressure and thermal load due to fluid temperature inside the pipe. The moment occurs because the load shall not exceed the plastic limit moment of the nozzle so that failure does not occur. For this reason, it is critical to study the limits of moments that arise in nozzles. This paper aims to determine the plastic limit moment in cylindrical pressure vessels due to torsion load with various pad thicknesses and diameters. The simulation was conducted using a non-linear finite element analysis method using ANSYS Workbench R2 Static Structural, following the modeling approaches from previous studies. The load-deformation curve based on the Twice Elastic Slope (TES) theory obtains the plastic limit moment for each variation simulation. The results indicate that the plastic limit moment (MpL) due to torsion load will increase by increasing the pad thickness until there is a certain optimum pad thickness, which the plastic limit moment (MpL) will not increase by increasing the pad thickness. In addition, the plastic limit moment (MpL) and deformation limit under torsion are lower than those observed for out-of-plane and in-plane moments. The result of this study is beneficial in increasing knowledge about the effect of pad thickness and diameter on the plastic limit moment of pressure vessels. It can be developed further to optimize the design of cylindrical pressure vessels based on ASME Section VIII Division 2.

Copyright

© 2025 The Author(s)

Open Access

Open Access This chapter is licensed under the terms of the Creative Commons Attribution-NonCommercial 4.0 International License (http://creativecommons.org/licenses/by-nc/4.0/), which permits any noncommercial use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license and indicate if changes were made.

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TY  - CONF
AU  - Petrus Lioe
AU  - Indraswari Kusumaningtyas
AU  - Rachmat Sriwijaya
PY  - 2025
DA  - 2025/07/01
TI  - Effect of Pad Thickness and Pad Diameter Variations on Plastic Limit Moment in Cylindrical Pressure Vessels Due to Nozzle Torsion Load
BT  - Proceedings of the 10th International Conference on Science and Technology (ICST 2024)
PB  - Atlantis Press
SP  - 86
EP  - 97
SN  - 2352-5401
UR  - https://doi.org/10.2991/978-94-6463-772-4_10
DO  - 10.2991/978-94-6463-772-4_10
ID  - Lioe2025
ER  -