Original Date: 11/03/1996
Revision Date: 01/18/2007

Oak Ridge’s Y-12 Plant uses hydroforming techniques to produce precise, thin-wall part geometries that would otherwise be difficult and expensive to manufacture with standard manufacturing techniques. Although hydroforming equipment can easily be obtained from commercial vendors, the procedure requires considerable expertise to achieve a low-percentage part and/or tool-die rejection rate and maintain efficiencies, precision, and consistent quality. Many highly-skilled key individuals who obtained this expertise over the years are approaching retirement age. The Hydroforming Tool-Die Design Advisory (HTDA) effort extracts this knowledge and makes it available to less-experienced individuals. In addition, the integration of modern computer techniques into various aspects of hydroforming extends a facility’s assets and allows its employees to reach higher skill levels.

Y-12 needed a systematic approach that could collect all-known pertinent data and information, minimize its impact on current hydroforming activities, and be consistent with future computerization and integration (long-term strategic) plans. Over the years, research determined that math modeling would not provide all the answers and only worked best with very specific, well-defined issues. HTDA uses geometry, forming problems, requirements, constraints, guidelines, and any other pertinent information. Based on reduced-order, feature-based modeling instead of traditional finite-element modeling, HTDA can operate within seconds as opposed to several weeks. The system selects the tube size and performs a bending analysis to determine factors such as optimal procedures, machine parameters, and machine setups for making quality parts with low rejection rates.

General Motors implemented HTDA for the production of a typical, water-die hydroformed part used in automotive applications. After bend analysis, the system significantly reduced the number of dies necessary to fabricate the part. In addition, HTDA successfully replicated a reoccurring failure which the 3-D finite element model failed to identify.

By capturing design and process knowledge, HTDA is very effective in determining potential problems which usually would not be discovered until the latter stages of production (after the dies have been fabricated and tested). The system can also be used in production planning, such as concurrent engineering activities or optimal production scheduling, to make quality parts with low rejection rates.

For more information see the Point of Contact for this survey.