The Naval Sea Logistics Center is working to defend the Navy from “its worst enemy”—rust—with a new generation of corrosion-resistant covers for topside equipment.
The Envelop Protective Cover, developed for the Navy by Chicago-based Shield Technologies Corp., shields the equipment from salt water spray, absorbs condensation, and allows vapors to evaporate, arresting the corrosion cycle, the Navy says.
Corrosion is accelerating aging of Navy ships at an alarming pace. The Navy now spends almost $2.5 billion per year—about 25% of its total maintenance budget—on corrosion control and repair. The General Accounting Office has called corrosion the Navy’s No. 1 controllable cost.
Development of the triple-patented, four-layer, high-tech cover was underwritten by a Small Business Innovative Research Grant issued by the Navy.
The cover is said to reduce corrosion by as much as 90% over traditional tarps, while requiring less investment than enclosed and stationary dehumidifier systems. The reduced corrosion translates into reductions of up to 80% in the average daily maintenance of weapon systems and other equipment, the developer says.
The custom-fitted covers not only shield components, but they are breathable, allowing vapors to evaporate from underneath. Special materials absorb condensation and water trapped under the cover and hold them away from the metal until they evaporate. Meanwhile, long-life vapor corrosion inhibitors are released into the enclosed atmosphere, preventing oxidation.
Shield Technologies says the covers “dramatically improve military readiness by reducing the number of hours spent on corrosion prevention.”
In a field test, the covers slashed the amount of time required to maintain a .50-caliber gun from one hour a day to one hour every two weeks, the company says.
In another Navy field study, an Envelop cover saved an estimated $30,000 in damage and maintenance costs for a 25 mm gun in its first two years of use.
The technology has been adapted to tailor covers for more than 150 unique components on every class of surface ships, including deck guns and close-in weapons systems.
Other Military Applications
The technology has been successfully transferred to the U.S. Army, U.S. Marine Corps, U.S. Coast Guard and allied navies, in the form of rapid securing devices for SH-60B Seahawk helicopters; M777 lightweight howitzers; common remotely operated weapons stations (CROWS); counter rocket, artillery, mortar systems; and more. The Marines use the covers on all howitzers in their inventory and for other combat equipment.
The Naval Sea Logistics Center’s work began with an inventory of the covers currently on board ships to identify the quantities required. Once funding was secured, the Center created more than 3,000 requisitions for providing specific types and quantities of covers to the ships.
Currently, the Center is monitoring 89 different types of Envelop Protective Covers for distribution to 155 surface ships—a total of 8,031 protective covers at a cost in excess of $10 million.
The significance of the covers was underscored in September by the personal visit of Rear Admiral James P. McManamon, Deputy Commander for Surface Warfare, SEA 21, to the USS McFaul. His visit marked the official turn-over of the protective covers to the surface fleet.