Comprehensive Study and Analysis of Tapping and Nut Bolt Joints Used in Subsea Applications

Abstract

Threaded fasteners and tapping joints are essential for the structural integrity and leak-proof performance of subsea systems subjected to high external pressure, aggressive corrosion, and complex cyclic loading. This study presents a comprehensive, systematically structured review of experimental, analytical, and numerical investigations of nut–bolt and threaded connections used in deep- and ultra-deepwater applications. The literature is classified based on governing performance parameters, including thread engagement mechanics, preload retention, fracture behavior, corrosion–fatigue interaction, material evolution, and environmental effects such as hydrostatic pressure and thermal gradients. Experimental observations are critically synthesized with finite element modeling to interpret stress distributions, failure mode transitions, and sealing reliability. A comparative material selection framework is developed by linking conventional carbon steels with advanced alloys such as duplex stainless steels, titanium, and nickel-based materials for long-term subsea service. The novelty of this review lies in the development of an integrated, design-oriented framework that unifies engagement optimization, preload control, fracture modeling strategies, material selection, and environmental coupling into a single engineering interpretation for subsea fastening systems, which has not been collectively addressed in previous studies. The presented synthesis provides direct application guidelines for improving the design, analysis, and operational reliability of subsea bolted joints.