Page 44: of Marine News Magazine (April 2015)

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COATINGS

Quietly Controlling

Noise with the help of Coatings

U.S. Navy’s AGOR Research Vessels are built to be as operationally quiet as possible.

That’s where Mascoat’s Sound Control-dB coatings come in.

By Joseph Keefe tions and noise to minimum. The coating has advantages over conventional methods of sound damping, such as ap- plication rate, cost savings, weight to damping ratio, cor- rosion protection, and product lifespan. That said; the ul- timate solution for all vessels will involve a combination of many methods, starting ? rst in the design of the vessel itself.

The Design Shop Weighs In hen the U.S. Navy began its design and build For this project, Guido Perla & Associates, Inc. (GPA) program for its newest generation of research was hired by Dakota Creek Industries (DCI) to provide

W vessels, it speci? ed that the vessels had to be as a Basic Design during the Phase I NAVSEA design com- quiet as possible. That’s because a large part of ocean research petition. When the team’s design was awarded the build involves listening and excessive ship noise tends to negate contract in October 2011, GPA’s engineers and Naval Ar- that effort. Achieving the goal of an exceptionally quiet ves- chitects went to work on the detail design and production sel, the vessel’s design team employed a variety of methods engineering. GPA and DCI have partnered on many proj- to meet the Navy’s exacting standards, choosing systems, de- ects in the past ranging from a Navy Sea Jet, an Advanced ? ned equipment locations and designed special installation Electric Ship Demonstrator, to ? re boats, ferries, tugs and methods with acoustics as a priority. One of those methods trawlers. Puget Sound-based DCI is a shipbuilding and re- involved Mascoat’s Sound Control-dB coatings. pair facility specializing in steel and aluminum vessels up

A quiet vessel allows for ocean research, but there are to 450 feet and 275 tons located in Anacortes, WA. The many compelling reasons for any workboat operator to shipyard began construction on AGOR 27 in mid-2012.

achieve the same standard. These include the new Mari- Stefan T. Wolczko, naval architect and GPA’s Business time Labor Convention (MLC2006), the ABS Habitabil- Development Manager also weighed in on the merits of ity notations and, when applicable, the Special Purpose Mascoat in the design process. He told MarineNews in

Ships (SPS) Code also can also into play. And, for U.S. March, “GPA has many options available in the toolbox vessels operating in international waters where MLC2006 for vibration and noise abatement, and GPA would not is in force, a U.S. Coast Guard issued Statement of Volun- recommend a coatings-based solution as a ‘one-or-the-oth- tary Compliance (SOVC) can be an important benchmark er’ alternative to other, more effective solutions. Coatings in determining whether a vessel can operate there (or not). to reduce structure-borne vibration can act as a supplement

Those guidelines involve many variables, among them; to other methods of noise and vibration reduction, but are sound damping to ensure the comfort of the crew. not considered a standalone solution. Signi? cant reduc-

Sound Damping Coatings such as Mascoat Sound Con- tion in noise and vibration are achieved primarily by use of trol-dB have become a trusted solution to help keep vibra- proper structural design in foundations and surrounding

April 2015

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