Overview
Advanced Structural Joining Methods (2000-093)
Project Team:
- Bender Shipbuilding & Repair
- Caterpillar
- Edison Welding Institute
- IPSCO Steel
- Alabama Laser
August 1999 - August 2003
NSRP ASE Investment: $2.2M
Industry Investment: $4.3M
Objective:
Reduce the time spent in both fitting and welding of structural steel using laser cutting, new joining strategies, precision forming and laser welding.
Summary:
Bender Shipbuilding and Repair Co. in Mobile, Alabama, was the first U.S. shipyard to demonstrate and implement the practical application of laser steel cutting and use it to build ships at significantly reduced total cost and cycle time. Using the laser cutter, Bender achieved an 8% reduction in steel plate usage, a 30% reduction in steel cutting costs and a substantial drop in fitting and welding labor on sequential, identical ship projects. Based on these results, the Navy CVN and DD(X) programs funded additional R&D for laser fabricated tee beams. Collaborative research allowed Bender to leverage laser research by Caterpillar on heavy equipment. Bender worked with IPSCO Steel to define the steel qualities suitable for laser cutting shipbuilding activities. Bender’s laser is unique in that it can cut steel plates as large as 13 feet wide and over 1 inch thick. The bed of the laser is 147 feet long, which means as many as three 40-foot-long plates can be on the cutting platform at once. Bender purchased the six kilowatt, carbon dioxide laser for precision cutting of large steel plates. While Bender owns the laser and press break, it contracts out the day-to-day operating business of the shop to Cutting Edge Metal Processing, Inc. in Mobile. “What we have found is that the amount of welding rework in the shipyard has dropped drastically,” said Bob Lewis, General Manager of Cutting Edge. “This is critical in shipbuilding, because unplanned gaps between steel plates cause additional welding and distortion – both of which increase costs. This would be true in almost any steel fabrication, whether or not it relates to shipbuilding.”
The company has invested approximately $1.5M in purchasing and installing the Tanaka LMXIII laser, and an additional $1M in a 1,100-ton CNC press break. Bender made the decision to purchase the laser after getting involved in the National Shipbuilding Research Program. He explained that through NSRP, Bender executives were able to learn about international shipbuilding practices. The European philosophy of building ships with the most accurately cut parts is a philosophy that appealed to Bender executives. To accomplish this in Mobile, Bender purchased the state-of-the-art laser. Typically, shipyards use a plasma machine to cut steel plates, a method that relies on hot jets of air to burn through steel. While this process works well for many shipyards, the plasma machine did not offer the accuracy Bender was looking for to improve its processes. GD Electric Boat installed a high powered laser cutting system in their new steel processing facility based on Bender’s success.
Key Deliverables:
Request Final Report from NSRP – Limited Distribution authorized to the U.S. shipbuilding industry and NSRP ASE Program representatives