Improving SHT tile manufacturing and application processes will reduce cost and increase reliability while in service. U.S. Navy photo
The Navy Metalworking Center (NMC) is conducting a ManTech project to evaluate several potential improvements for cost reduction and performance enhancements.
Improving the design, manufacturing, and application of Special Hull Treatment (SHT) on Virginia class submarines (VCS) can reduce installation and maintenance costs. SHT is necessary for VCS to meet operational requirements and is installed via a bond-in-place (tile) or mold-in-place process, depending upon the location on the hull. Improvements to materials and / or installation processes will lower the cost to manufacture the tile, decrease installation labor and rework, lower overall installation time, and maintain reliability.
The technical scope of this project is based on a General Dynamics Electric Boat (EB) review of the bond-in-place installation process and materials that identified the following areas for further investigation:
• Modifying tile features to aid in installation
• Improving tile manufacturing processes to reduce cost and rework
• Improving installation materials and processes to reduce installation time and maintain reliability.
The Integrated Project Team (IPT) will establish requirements, identify candidate processes / materials, perform multi-staged technical evaluations, and generate a cost savings analysis to verify project metrics are being met.
This project will save an estimated $600K per hull for new construction and $500K per year for fleet maintenance. The bulk of the cost savings will result from improvements to the tile manufacturing process via better casting techniques and machining methods, which will significantly cut material waste. A substantial reduction in labor will also be realized by improving the tile design and application process.
The results of this project are scheduled to be implemented for new construction at EB starting with SSN 800 in 2018. Implementation for in-service ships will be coordinated through PMS 392 in 2016.
General Dynamics Electric Boat Corporation
Naval Surface Warfare Center, Carderock Division
PMS 450 Virginia Class Program Office
PMS 392 - Strategic/Attack Submarines