Norfolk Naval Shipyard (NNSY) held a ribbon-cutting ceremony to celebrate the completion of the first Craft 60 Ton Portal Crane mid-life overhaul Service Life Extension Plan (SLEP), July 11.

The execution of this SLEP across the corporation is expected to take approximately eight years as there are 22 total of this class of crane across the shipyards; 14 at NNSY with the others at Puget Sound Naval Shipyard (PSNS) and Portsmouth Naval Shipyard (PNSY).

The SLEP project is a result of the collaboration between the shipyards (NNSY, PNS and PSNS), Naval Sea Systems (NAVSEA) and the Navy Crane Center addressing replacements of old systems, upgrades to new technology and design changes to meet the latest requirements.

The first dock crane (DC) to be completed, DC37, is critical to the success of the shipyard's mission in ship repair and overhaul. Portal cranes are built to have a 50-year life span. DC37 is currently 25 years old and the mid-life overhaul is expected to extend its lifespan another 25 years, a significant savings to the Navy over time.

"The cost of the overhaul is approximately $2 million and includes all systems required to reach the full lifespan expectancy," said Curtis Sturkie, chief engineer for NNSY's lifting and handling department. "If we had to replace the crane we'd spend upwards of $20 million."

Because the control systems in the cranes are obsolete, components are either unavailable or too expensive, so the overhaul also provides spare parts to shipyard inventory which can support sustainment of the remaining cranes awaiting overhaul, said Sturkie.

The overhaul includes replacements of old systems such as electrical controls, computers, breakers, diesel generator, cab master switches, and operator's console. It also includes additions and upgrades such as the load moment indication (LMI), whip hoist wire rope, new hoist limits and travel wheel lubrication system.

The overhaul revitalizes the crane for its 21st century mission and meets new environmental and safety regulations. For example, the new diesel generator creates significant savings for the Navy because it requires less fuel consumption and meets the latest Environmental Protection Agency (EPA) tier level for the environment, explained Sturkie.

The addition of newer technology also allows more efficient operations and the ability to complete a job in a timely manner, as safely as possible

"One of the things we did when we designed the SLEP was to have the crane operators involved," said Sturkie. "They had a copy of the drawings, reviewed and approved them."

"The updates give the operator more knowledge of what is going on," said Shawn Herring, a 19-year veteran crane operator. "With the new LMI system, operators know within two percent the actual weight they are picking up and it automatically provides warnings followed by hoisting lockout and prevents further hoisting, if required, to prevent overload."

As the Navy's mission to maintain freedom of the seas is ongoing. As one ship leaves the yard another takes its place. This means the cranes are in continuous operation. These overhauls are just another way the shipyards supports that mission, said Sturkie.

For more information, visit http://www.navy.mil, http://www.facebook.com/usnavy, or http://www.twitter.com/usnavy.

For more news from Norfolk Naval Shipyard, visit http://www.navy.mil/.