Development and Assessment of an Environmentally Compliant Corrosion Stain Remover for Navy Topside Coatings
Colton Spicer, Cameron Miller, Jimmy Tagert, and John Wegand, Naval Research Laboratory, and Sumathi Gulati, Excet, Inc., Bruce N. Nelson, Battenkill Technologies, Inc
The presence of rust staining on surface ship topside and freeboard areas has been a continuing cosmetic problem for the U.S. Naval Fleet. In an effort to maintain the appearance of a well maintained ship, the U.S. Navy is estimated to expend more than $1.0M annually on silicone alkyd topside coatings, governed by Navy specification MIL-PRF-24635, purely for cosmetic over-coating purposes.1 With the introduction of polysiloxane topside coatings, cleaning becomes a viable and more cost effective alternative to aesthetic re-coating due to polysiloxane’s cleanability, toughness, superior color retention, gloss retention, and service life compared to the current silicone alkyd coatings. An effort was executed, to leverage the inherent benefits of polysiloxane coatings, to investigate, to assess or develop, and to implement an effective corrosion stain remover in the Navy with the focus of reducing both maintenance costs and time. Novel evaluation techniques were developed to accurately detect and quantify the performance of stain removers on polysiloxane coatings in both laboratory and shipboard tests. Lessons learned during field demonstrations were used to create, develop, and implement polysiloxane cleaning processes for Ship’s Force to follow with assistance from the U.S. Navy Corrosion Control Assistance Team. Recent shipboard demonstrations have proven that significant cost avoidance can be realized through a reduction in maintenance time, annual maintenance costs, topside weight, and hazardous waste. The Naval Research Laboratory (NRL) intends to reduce the impact on maintenance by eliminating and overcoming the cosmetic overcoat paradigm through this effort, allowing the Navy to realize the projected extended service life from the polysiloxane topside coatings.