Fabricated trunnions for heavy lift

Abstract

This paper presents the general test arrangement and results for seven tests on fabricated pipe trunnions with two diameter-to-thickness ratios and three different structural arrangements. The results highlight the significant contribution of side braces to the overall pipe trunnion strength, which current design practice does not take into account. Two distinct failure modes, shear failure of the brace and plastic failure of the the chord face, were observed. For thin-walled chords, the provision of a through shear plate was found to be ineffective, while pipe trunnions with a through brace arrangement were seen to offer significant strength enhancement to simple X-joints. The through pipe brace offers more efficient load transfer than a conventional shear plate arrangement and is a good design alternative for pipe trunnions.