Efficient Welding Fabrication of Extruded Aluminum Mat Panels

摘要

The program had the following main objectives: to design and procure weldedextruded access/egress (A/E) mat panels, to determine feasibility of and to provide means for fabrication of Ribbon Bridge (RB) and Light Assault Bridge (LAB) deck panels using the technology developed under this program, to develop advanced equipment and technology for assembling and welding of A/E mat panels, and to study mechanical and metallurgical properties of welded joints. The existing practice is to design and build roadway mat panels (or bridge deck panels) from wide, single-piece extruded 6061-T6 aluminum components. In order to avoid difficulties associated with procurement of large circle-size extrusions, which are expensive and not readily available, the panel cross-section was constructed from smaller extruded elements using welding. In this respect, various aspects of weldment design were studied, including design of welded joints, and fatigue analysis of their performance since the panels will be subjected to severe environment and heavy load conditions. Also, a procurement base for extruded panels was explored through analysis of data obtained as a result of an industry survey. A state-of-the-art experimental automation fabrication system was developed for assembling and welding of long extruded components. It allows two longitudinal butt welds between three subpanels to be performed simultaneously on each side of the subpanels to form a full-size mat panel up to 28 in. (711 mm.) wide-,and up to 13 ft. (6,934 mm.) long, with a possible extension up to 28 ft. (8,534 mm.) for fabrication of bridge deck panels. A unique fixture was developed as an integral part of the system to meet the requirements of a welding procedure developed to offset complicated metallurgical reactions typical.