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A state-of-the-art summary has been prepared on the subject of airfield marking paints. Information is presented on the composition of such paints, federal specifications, available test methods, reflectorization methods, deterioration mechanism, skid-resistance relationships, surface preparation, application requirements, and alternative marking systems. Information on traffic paints was used where it was relevant. A summary of recommended airfield marking practices was prepared to provide practical information to people responsible for airfield marking. While currently used airfield marking practices are considered adequate, improved materials and/or methods may significantly reduce maintenance costs and may be necessary for more restrictive regulations that are anticipated. (Author)

A state-of-the-art summary has been prepared on the subject of airfield marking paints. Information is presented on the composition of such paints, federal specifications, available test methods, reflectorization methods, deterioration mechanisms, skid-resistance relationships, surface preparations, application requirements, and alternative marking systems. Information on traffic paints was used where it was relevant. A summary of recommended airfield marking practices was prepared to provide practical information to people responsible for airfield marking. (Author)

Field tests were conducted at Port Hueneme, California, and Panama City, Florida, on an adhesive developed at CEL that is capable of being applied underwater. The tests indicate that sandblasting rusty steel results in bonding as strong or stronger than wire-brushed surfaces and in stronger bonding than on waterblasted surfaces. Bonding strengths of field-applied specimens were about one-sixth to one-third those of laboratory-applied specimens., Supplement to report dated Dec 74, AD-A004 938.

A series of alkyd resins were prepared that had tin chemically bonded to them. These resins had more resistance to fungal growth than did the original alkyd resins from which they were prepared. This resistance does not appear to be lost as readily by leaching with rain as that of a resin to which bis(tri-n-butyltin) oxide is added as a preservative.

Several underwater-applied epoxy coatings were developed for protecting steel structures in seawater. The more promising formulations were laboratory and field tested at different times using a brush, a roller, and a curved plastic applicator developed by the Navy Coastal Systems Laboratory. The coating that was the easiest to apply underwater is now marketed by a commercial supplier. Sandblasting was found to be the best method of preparing steel surfaces for painting underwater, and waterblasting was the next best of the five methods tested. (Author)

The reaction products of fatty acids and bis(tributyl tin) oxide are combined with an unreacted alkyd resin, or an alkyd resin, which has been reacted with an organotin compound, in concentrations to form homogeneous blends that will air cure and are capable of being pigmented to form durable paint films having relatively large tin contents and great resistance to microbial growth. Author), Supersedes PAT-APPL-661 472-76, AD-D002 463.

This patent application concerns a two component epoxy paint for application to an underwater surface. The paint displaces the water on the underwater surface and bonds tightly and permanently to it, sealing concrete surfaces and protecting steel surfaces from corrosion. One component consists of a viscous liquid epoxy, a corrosion inhibitive pigment, and surface active agents while the other component is an amine adduct curing agent.

Two buoys of FRP/polyester resin shell were fabricated by a hand lay-up and by a spray- p technique. The two plastic mooring buoys have provided goodservice as part of moorings for the Fleet in San Diego Bay for a period of5 years; the hand lay-up shell buoy is in appreciably better conditionthan the spray-up shell buoy. A third plastic buoy was fabricated with animproved design and was placed in service in Pearl Harbor; after 2 years,the buoy is in excellent condition. A cost analysis indicates thepracticality of using plastic rather than steel buoys as components ofFleet moorings. An annual savings of about $6,150 per Class BB mooringcan be achieved using a plastic buoy in conjunction with cathodicallyprotected ground tackle. A PURCHASE SPECIFICATION FOR A PLASTIC MOORINGBUOY IS INCLUDED FOR USE BY Naval field activities. (Author, modified-PL)

An investigation was continued into the cathodic protection of fleet moorings, both the underwater portion of the buoy and the ground tackle. Sacrificial zinc anodes used on the ground tackle were specially cast on steel chain links so that they became an integral part of the ground tackle. The tight riser chain secured to the peg-top buoy had the required electrical continuity between chain links to permit the flow of current, but it was necessary to use a steel cable woven through the links of each of the ground legs and periodically joined to them to impart complete continuity between links. The cathodic protection system was shown to impart complete protection from corrosion to both the underwater portion of the buoy and to the ground legs, whether the latter were on either a sandy or a muddy bottom. It is estimated that this system can provide such protection for a total of at least five years., See also Part 4, AD839338.

An investigation was conducted into the use of specially cast zinc anodes to cathodically protect the ground tackle of a fleet mooring. While part of the mooring was completely protected by these anodes, a lack of good electrical continuity in parts of the ground legs prevented complete protection there. A cable joined periodically along one of the ground legs provided the necessary continuity and permitted complete protection of the leg., See also Part 1, AD617259.

A test program has been initiated that is aimed at reducing the maintenance costs associated with the recoating of deteriorated pontoon camel floats. Three 2-coat protective coating systems have been applied to pontoons on three test floats, and a material and labor cost analysis has been made on coating pontoons with each of these systems. A separate phase of the investigation is aimed at corrosion mitigation by cathodic protection. One of the test floats is currently being protected with zinc anodes, another with aluminum anodes, and the third float is serving as an unprotected control. After six months service to the fleet, the test pontoon camel floats were in good condition. No coating deterioration was noted, and the cathodic protection systems were providing electrical potentials that insure complete protection from corrosion to any exposed steel.

A test program was initiated to reduce the maintenance costs associated with steel pontoon camel floats. Three two-coat protective coating systems were applied to pontoons on each of three test floats. One test float was cathodically protected with zinc anodes, another with aluminum anodes, and the third without cathodic protection was designed to serve as a control., See also Part 2 dated Jun 1968, AD837192.

A surveillance system for monitoring tank-to-water potentials in cathodically-protected water storage tanks was fabricated under contract and installed and tested in a tank at CBC, Port Hueneme, California. After very minor modifications the system performed well for a two year period.

A 7-year program of field testing metal rods for electrical grounding was conducted. Single rods of galvanized steel, copper-clad steel, Ni-Resist cast iron, type 302 stainless steel, type 304 stainless-clad steel, zinc, magnesium, and aluminum were tested along with couples of these to mild steel rods. Sets of both single and coupled rods were removed, cleaned, and weighed after 1, 3, and 7 (or 5) years. Potential, resistance, and current measurements were made monthly as far as practicable. Weight losses and electrical data were analyzed for correlations. It was concluded that type 302 stainless steel and type 304 stainless-clad steel rods were the best choices for general use.

ALTHOUGH A NUMBER OF METHODS ARE REPORTED IN THE LITERATURE FOR THE SEPARATION OF SATURATED HYDROCARBONS FROM CREOSOTE, NONE WAS FOUND TO GIVE A COMPLETE SEPARATION. A CHROMATOGRAPHIC ADSORPTION PROCEDURE HHAS BEEN DEVELOPED WHICH CAN SEPARATE THE SATURATED HYDROCARBONS FROM THE OTHER CONSTITUENTS OF CREOSOTE. DAVISON GRADE 922 SILICA GEL IS USED AS THE ADSORBENT, AND N-HEXANE IS USED AS THE ELUENT. SATURATED HYDROCARBONS ADDED TO WHOLLY AROMATIC CREOSOTE WERE RECOVERED QUANTITATIVELY BY THIS PROCEDURE. ULTRAVIOLET SPECTRAL ANALYSES OF THE SATURATED HYDROCARBON FRACTIONS SEPAARATED FROM BOTH CREOSOTE AND CTEOSOTE PETROLATUM BLENDS PROVED THE ABSENCE OF AROMATIC CONTAMINATION. SATURATED HYDROCARBONS SEPARATED FROM CREOSOTES PRODUCED AT LOWER CARBONIZATION TEMPERATURES WERE RELATIVELY NONTOXIC TO ADULT L LIMNORIA AND TO TEREDO LARVAE

An investigation was conducted into finding materials and procedures for mixing, applying, and curing rapid-setting epoxy adhesives under seawater. Separate formulations were developed for use at 5C and 20C. They were easily mixed and applied underwater from a plastic cartridge. A simple system of chemical heating was found to accelerate underwater curing, especially in cold waters.

A method for determining the elongation of free paint films is discussed. The method is more precise than the ASTM and Federal Test Standard methods which use the mandrel test, and it provides a more clear-cut differentiation between different coating films. A statistical analysis was performed on 10 experimental airfield marking paints using data from the free- film percent-elongation tests and from performance tests of the same coatings exposed in the field. The results indicate that there is a definite correlation between the percent elongation (flexibility) and the field performance of airfield marking paints. (Author)

Several materials and application procedures have been investigated for use in the in-place maintenance painting of steel piling. Coatings designed for application to dry sandblasted piling above the waterline have performed well for two years. Coatings designed for application between tides, so that they are wetted with seawater almost immediately after application, or for application underwater, have performed well for one year. Application above water was accomplished by conventional spraying. Part of the application between tides and a few feet below mean low water was accomplished by a special cofferdam designed for use on steel sheet piling. The rest was accomplished by brushing coatings specially formulated for underwater application. Surface preparation for the latter application was generally by underwater sandblasting, but cleaning with a pneumatic needle gun was also investigated. Laboratory testing indicated that needle gun cleaning was a promising technique.

This patent application concerns a two-component, rapid curing epoxy adhesive for use underwater; the adhesive, which is not activated by water, displaces water on the underwater surfaces and bonds tightly and permanently thereto. One component consists of viscous liquid epoxy and the other component contains a high functionality liquid polymercaptan resin and 2,4,6-Tri(dimethyl amino-methyl) phenol, plus a wetting agent and fillers.

A 3-1/2-year test program was conducted in San Diego Bay on the use of modern synthetic coatings in conjunction with sacrificial anodes for protecting steel pontoon camel floats from corrosion. The three two-coat, protective coatings systems performed very well, and the anodes provided complete protection from rusting to underwater portions of the floats. It was concluded that a combination of one of the coating systems and cathodic protection from sacrificial anodes can greatly reduce the maintenance costs associated with pontoon camel floats. The three coating systems consisted of two epoxy-polyamide systems and one zinc inorganic silate combined with epoxy-polyamide. (Author, modified-PL)

Two plastic mooring buoys, fabricated by a private contractor, were described in Part I of this study program. Each buoy had a steel framework filled with closed-cell polyurethane foam. On one buoy this foamed core was covered with an exterior shell of fiberglass cloth impregnated with polyester resin; on the other, the exterior shell was a sprayed-on coating of chopped fiberglass strands in polyester resin. This report, Part II, describes the 3-year in-service testing of these buoys in San Diego Bay. While both performed well, the hand lay-up buoy had much less deterioration than the spray-up buoy. Also, it was determined that plastic buoys have much lower maintenance costs than steel mooring buoys. An improved plastic mooring buoy was designed from the results of the testing program. This design utilizes hand lay-up construction of the outer shell with alternate layers of random chopped-glass mat and woven roving. Such a buoy was fabricated and is currently serving the Fleet at Pearl Harbor, Hawaii. (Author), See also Part 1, AD-612 055. Limited number of copies containing color other than black and white are available until stock is exhausted. Reproductions will be made in black and white only.

A test program had been initiated to reduce the maintenance costs associated with steel pontoon camel floats. Three 2-coat protective coating systems had been applied to pontoons on three test floats. One test float is cathodically protected with zinc anodes, another with aluminum anodes, and the third float without cathodic protection is serving as the control. After two years of service to the fleet in San Diego Bay, the test pontoon camel floats were all in good condition. No coating damage, other than that caused by abrasion, was noted, and the cathodic protection systems were providing complete protection from corrosion to the underwater portions of the floats. (Author)

A simple procedure and test kit have been developed for identifying the generic type and general composition of cured or weathered paint films. The procedure includes pyrolytic and burning tests, solubility tests, and tests for the detection of such elements as chlorine, nitrogen, lead, and mercury. All the tests can be performed with simple equipment by field personnel having little or no prior laboratory experience. The procedure and test kit were proven by successfully identifying 61 weathered paints that might be encountered at Naval shore activities.

A surveillance system for monitoring tank-to-water potentials of cathodically protected steel water storage tanks was designed and tested. The system used permanently attached silver/silver chloride reference half-cells, which were joined by electrical wiring to a switch box at ground level. The potentials could be accurately read at the switch box on a portable meter. The system performed well during the 4-year test period. The surveillance system was later modified so that the existing anodes and reference half-cells could be used with an automatically controlled rectifier unit to form a completely automatically controlled cathodic protection system. This system maintained stable tank-to-water potentials for the 2-year test period. (Author)

Two plastic mooring buoys have provided good service as part of moorings for the Fleet in San Diego Bay for a period of 4 years. One buoy with a hand lay-up fiberglass- reinforced polyester shell is in appreciably better condition than the other one with a spray-up shell of fiberglass-reinforced polyester resin. A third plastic buoy with an improved design is in excellent condition after 1 year of service to the Fleet in Pearl Harbor. An analysis of the costs of purchasing and maintaining steel and plastic mooring buoys is presented. It indicates that after the present supply of World War II mooring buoys is exhausted, the Naval Facilities Engineering Command field activites shoud use plastic mooring buoys as replacement becomes necessary. (Author-PL)

A field exposure study was conducted on experimental airfield marking paints with relatively high flexibilities. While flexibility must be greater than the minimum required in Federal Specification TT-P-85b for good paint performance, a further increase in flexibility does not necessarily result in better performance. Short oil length alkyd and oleoresinous paints do not perform well; medium oil length paints performed very well; longer oil length paints generally performed somewhat poorer than medium oil length paints, especially for the alkyd formulations. While incorporation of organic plasticizers into paints generally increased flexibility, it did not usually improve the field performance. A statistical analysis of the test variables revealed the following: Oleoresinous phenolic varnish generally performed better than alkyd paint stripes. Lifting was greater for double-thickness thickness stripes than for single-thickness stripes. Cracking was faster for long oil than medium oil alkyd paints and for medium oil than for long oil oleoresinous paints. Medium oil paints had less cracking overall than long oil paints. There was generally less cracking and lifting with paints containing no plasticizer than those with one. Tricresyl phosphate formulations generally had less edge cracking and lifting than comparable formulations with dibutyl phthalate as a plasticizer. There was a high correlation between edge cracking and the lifting of slurry seal. (Author), See also Part 3, AD-643 202.

A study was conducted into the feasibility of cathodically protecting a fleet mooring. The original cathodic protection system utilized sacrificial magnesium anodes with automatic control heads designed to maintain the desired potential level. This system did not operate satisfactorily. A modification using uncontolled zinc anodes gave a higher level of protection to the buoy and riser chain but insufficient zinc was present on the ground legs to provide the necessary potential. (Author)

TO DESCRIVE THE CHROMATOGRAPHIC SEPARATION OF THE SATURATED HYDROCARBON FRACTIONS FROM A NUMBER OF CREOSOTES, PETROLEUM OILS, AND CREOSOTE-PETROLEUM BLENDS AND TO DESCRIBE THE TOXICITIES OF THESE CHROMATOGRAPHY FRACTIONS. RESULTS: AN EFFECTIVE METHOD OF SEPARATING SATURATED HYDROCARBONS FROM CREOSOTE AND PETROLEUM OILS WAS DEVELOPED. THE COKE OVEN CREOSOTES INVESTIGATED HAD EXTREMELY LOW SATURATED HYDROCARBON CONTENTS, WHILE CREOSOTES PRODUCED AT LOWER CARBONIZATION TEMPERATURES CONTAINED SIGNIFICANTLY GREATER AMOUNTS. THE SATURATED HYDROCARBON FRACTIONS FROM BOTH CREOSOTES AND PETROLEUM OILS WERE ALL RELATIVELY NONTOXIC TO LIMNORIA AND TEREDO

The invention comprises cathodic protection against corrosion of a stretched chain immersed in an electrolyte (sea water) in which sacrificial anodes of pure zinc are cast onto independent and spaced links of the chain. In order to ensure electrical continuity between adjacent links, a cable may be stretched therealong connecting each link to the spaced anodes. Thus when the chains are positioned in water having a high conductivity, e.g., sea water, the sacrificial anodes are consumed and an electrical current passes along the chain links so as to produce electrical potential and cathodically protect the chain from corrosion.