Detroit’s Lightweight Innovations For Tomorrow, or LIFT, Monday announced the creation of a new process that can save shipbuilders production costs, improve build time, and reduce distortion of lightweight materials.
“Developing better modeling to enable lightweight solutions is a big step forward for manufacturers across the country and across industries,” says Alan Taub, chief technology officer at LIFT. “Lightweighting is more than just substituting materials. It can be achieved through optimal engineering too.”
The so-called Joining-3 Project developed computer modeling to better predict where distortion, or warping, will occur when steel plates are welded together, ultimately reconfiguring the welding sequence. Using a U.S. Coast Guard Cutter unit as a test article, the project team demonstrated a 30 percent reduction in distortion and a 13 percent reduction in production costs compared to similar, previous cutter production units.
“As naval ship designs have trended toward using thinner and higher-strength materials to reduce structural weight and add new combat capability, controlling the quality and cost of distortion has increasingly and adversely affected the shipbuilding industry,” says T.D. Huang, principal engineer at Huntington Ingalls Industries, a company that worked on the project. “The LIFT project has provided an avenue to collaborate with world-class experts and systematically address thin steel distortion.”
The project took two years to develop. The team observed the baseline Coast Guard Cutter production assembly and collected distortion data at each step in the process; made 19 test panels featuring different variables and assembly sequences; used an integrated computational materials engineering (ICME) model to establish recommended fitting, welding, and assembly sequences for optimized distortion control; used the recommended procedures on a full-scale mock-up unit; and detailed process flows to determine the change in cost.
The project was led by Huntington Ingalls Industries’ Ingalls shipbuilding division, which is implementing the modeling process through ICME analysis and using the cost model to predict changes in design and the associated cost impact across all product platforms.
A follow-on project to evaluate advanced steel alloys for ICME implementation has been approved by LIFT for kick-off this summer.