Reduction of Overwelding and Distortion for Naval Surface Combatants. Part 2: Weld Sizing Effects on Shear and Fatigue Performance

Abstract

As high-strength thinner-steel implementation in ship designs increase, dimensional management becomes critical to control construction costs and schedule in ship production. In the U.S. shipbuilding industry, improvements to shipbuilding facilities and processing technology have not kept pace with the rate of change in ship design. Additionally, new designs using thinner steels are subject to legacy weld sizing criteria possibly leading to inappropriately sized welds on lightweight materials. These two factors result in widespread overwelding, causing severe plate deformation in naval vessels during construction and nonvalue added labor to correct as needed for fit-up tolerances. Historically, shear and fatigue strength data has been focused on the larger welds and thicker steel plates typical of the state of the practice when these legacy weld sizing criteria were developed. In order to optimize weld design and production in modern, lightweight naval surface vessels, there is a need to develop more accurate data about the performance of precision fillet welds for thin steels.