Monitoring of Arcing Condition in GMAW and Its Variants
Navy SBIR FY2008.2

Sol No.: Navy SBIR FY2008.2
Topic No.: N08-178
Topic Title: Monitoring of Arcing Condition in GMAW and Its Variants
Proposal No.: N082-178-0121
Firm: Adaptive Intelligent Systems
A020B ASTeCC Building
University of Kentucky
Lexington, Kentucky 40506
Contact: YuMing Zhang
Phone: (859) 257-6262
Web Site:
Abstract: This SBIR Phase I project is to prove the feasibility of an innovative weld monitoring technology. This innovative technology is characterized by (1) an innovative non-transferred arc sensor which responds to both surface conductivity and sensor-to-joint distance and can be used to monitor the joint geometry and possible surface contamination such as paint, oil, sand, etc. and (2) an innovative mechanism for determining the location of the arc root in relation to the joint geometry based on arc current and voltage waveforms. While the joint geometry and surface condition are the major variables whose deviations affect the arcing condition, the arc root location and arc current can be considered the results of their effects. The proposed monitoring method thus simultaneously monitors both the causes and results of possible arcing condition deviations.
Benefits: First, in addition to common contaminations, our technology also aims at monitoring possible lack of fusion and uneven penetration/weld distribution, the major problems identified by shipbuilding welding experts. Second, as the final stage in producing high value product (ships), all welds which do not meet quality standards require mandatory repair that is time-consuming and costly. High confidence on the quality of welds produced, as verified by monitoring record, can reduce the need for x-ray examination. Third, in addition to stopping the production of unsatisfactory welds, the technology proposed can also provide feedback to on-line adjust welding parameters to assure the production of quality welds without stopping the process. It can also actively improve the confidence on the weld quality thus further reducing the locations where x-ray examination is needed. Fourth, in past years, many monitoring technologies have been studied. Although they have achieved certain success in other environments, their application in ship welding is very limited especially for commonly used processes such as GMAW, SAW, and FCAW. Lack of innovative thinking from fundamental level may have been the cause. The proposed idea/concept has fundamental novelty (monitoring the arc root/deviation using arc related electrical signals rather than using images) and is a result of innovative thinking for special problems being addressed. Finally, the proposed technology aims at offering a single system/solution to all major arc welding processes used in ship structure welding. Hence, the proposed solution appears suitable for shipbuilding and its successful implementation is expected to provide shipyards monitoring technologies which can actually be used.