Project Number: S2831

Project Title: Semi-Automatic GTAW Welding Process

Period of Performance: JUN20 – FEB23

For the VIRGINIA Class submarine (VCS), General Dynamics Electric Boat (GDEB) currently uses labor-intensive manual gas tungsten arc welding (GTAW) operations and processes for cladding, welding pipe, welding tanks with difficult to weld alloys, and some structural welds. Manual GTAW is very slow, particularly for large-diameter circumferential welds. Additionally, it requires a high level of skill, due to the dexterity required in using both hands independently (i.e., one hand to move the welding arc along the joint and the other to feed the filler metal).

This Center for Naval Metalworking (CNM) project will use semi-automatic GTAW equipment to increase throughput for pipe welding, cladding, and other applications to meet the demands of the VIRGINIA Payload Module (VPM) and COLUMBIA Class submarine (CLB).  This project assessed and selected a semi-automatic GTAW welding system by EWM TIG Speed.  This system was used to evaluate various shipyard applications, including tank welds, cladding inside of tanks, pipe welding, and other applications.

The capabilities of welding equipment have advanced enough to enable replacing manual GTAW with semi-automatic GTAW, thus eliminating production delays by producing welds of consistently higher quality. The semi-automatic GTAW process is more productive than conventional (manual) GTAW and produces higher quality welds with the potential for fewer defects, such as lack of fusion. As a result, the new process will improve precision, reduce labor costs, and improve schedule performance.

Phase 1 defined the requirements and developed welding parameters.  In Phase 2, a test plan was created and executed to determine the acceptability of the semi-automatic GTAW process in the shipyard environment.

Semi-automatic GTAW will enable better quality welds at higher deposition rates compared to manual GTAW. It has the potential to be two-to-five times faster than manual GTAW and requires less-skilled welders. GDEB projects that this effort will result in estimated five-year savings of $801K for VCS, $9.4M for VPM, and $4.2M for CLB. This equates to total five-year cost savings of $14.4M and a return on investment of 4.46.

Now that the Semi-Automatic GTAW Welding Process ManTech project has successfully completed, the results will transition to the GDEB facility. GDEB anticipates implementation in the second quarter of fiscal year 2024.