The Alaska Ocean, at over 376feet in length, is one of thelargest fishing vessels in the

U.S. It’s also one of the mostsophisticated — a designationapplying not only to the on-board electronics but to the coat-

ings protecting the high-impactdeck areas as well.

The huge trawler/processorchurns through the chilly, blue-gray

waves of the North Pacific Ocean andthe Bering Sea, harvesting and processing

Alaska pollock and Pacific Whiting to pro-duce surimi, better known as imitation crab-meat. Owned by Alaska Oceans Seafood,The Alaska Ocean has the capacity to har-vest and process more than 500 metric tonsof fish per day during each of the approxi-mately 220 days per year she spends at sea.

Completely rebuilt more than 12 years agoin Norway and converted into thetrawler/processor she is today, the AlaskaOcean represents an initial investment of morethan $60 million. It’s easy to see why keepingsuch an investment ship-shape is a high priori-ty for her owners.

That consideration led management to takea pioneering step by considering polyurea coat-ings for high-impact deck areas. Pure, 100-per-cent polyurea coatings, made possible by rela-tively recent advances in coatings technology,offer ultra-high film build plus outstandingabrasion, chemical and corrosion resistance.They also dry in as little as 30 seconds.

Polyurea coatings are coming into wideruse across many industries, and the marinemarket is no exception. Above the water line— and currently being evaluated for surfacesbelow the water line — these coatings can bevery effective in protecting steel, aluminumand fiberglass for areas ranging from decks tofish hold liners and bilge liners.

TWO-MONTH DRY DOCKThe two-month dry dock period the

Alaska Ocean underwent this spring repre-sented anything but idle time. “We werescheduled into dry dock specifically to per-form inspections of our rudder and tailshaft,”says Cory Kaldestad, the Alaska Ocean’s portengineer who oversees vessel maintenance. “Atthe same time, we continued to upgrade ourfishing gear, fish-finding equipment and fac-

C O AT I N G S S O L U T I O N S / S P R I N G 2 0 0 412

The Alaska Ocean just before it left dry dock to go pier side to finish

the painting project, including the polyurea application.

Polyurea proves effective ontrawler’s high-impact areas

USING POLYUREACOATINGS FORCOMMERCIAL MARINEAPPLICATIONS

USING POLYUREACOATINGS FORCOMMERCIAL MARINEAPPLICATIONS

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FEATURE ARTICLE

Pete Judt,Assistant

Foreman, paint

department at Todd

Pacific Shipyards in

Seattle.

tory process systems, as well as perform rou-tine maintenance on our engines and varioussystems in the engine room and vessel. Thisincludes getting a quality paint job.”

Kaldestad was familiar with many of thebenefits of polyureas. Planning ahead, he hadarranged for a test area of Sherwin-WilliamsEnviroLastic® Polyurea to be applied and test-ed on the trawler for one fishing season. It hadperformed quite well, so Kaldestad was enthu-siastic about trying the coating on deck areas.

“There are areas on our boat where, duringnormal fishing and offload activities, a standardcoating will be destroyed by the repeatedimpact of hard, heavy objects,” he says. “Oncethe coating is destroyed it’s hard to stop rustfrom spreading. Based on the test we conduct-ed and the coating’s performance characteris-tics, we are anticipating that EnviroLasticPolyurea will last for years without failing.”

Ray Meador, a marine specialist withSherwin-Williams Industrial and MarineCoatings group, says polyurea coatings are idealfor marine applications for many reasons, includ-ing the need for fast job turnaround in dry dockto keep upgrades and repairs on schedule.

“Polyureas hold up where other systemswill fail,” Meador notes. “The fact thatpolyurea coatings are not sensitive to mois-ture and humidity during curing means theycan be applied within a wider window oftemperatures and weather conditions thantraditional coatings.

“They’re also an excellent choice when fastcuring applications are applied in high humidi-ty or low temperature conditions and whereextreme abrasion resistance and a high filmbuild are required,” says Meador.

LEAPING INPete Judt, Assistant Foreman for Todd

Pacific Shipyards in Seattle, and composite crewassistant foreman Ricky Roulst, have a com-bined total of more than 55 years of marinepainting experience. They supervised a crew ofup to 37 workers involved in the surface prepa-ration and painting of the Alaska Ocean. “The

application of polyurea is new to ships,” saysJudt. “There aren’t too many vessels with thiscoating technology installed anywhere.”

Before painting, the Alaska Ocean under-went a major repair. “There was a big dent inthe steel in the forward end of the boat underthe bow thrusters, probably caused by theimpact of big waves hitting the boat,” saysRoulst. “We took out a 12-foot by 12-footpiece of steel and replaced it with new steel.”

On the underwater hull, a copper slag blastmedia with a water ring was used to removecorrosion, grime and marine growth that hadattached itself to the bottom of the boat.“Water rings are mounted just behind the blastnozzle,” explains Roulst, “so water is projectedaround the blast stream, allowing a significantreduction in dust emissions.”

Surface preparation activities at the free-board line and above including the topside

structures involved several dif-ferent blasting techniques. Allareas up high were power-toolprepared using sanders andneedle guns to prevent exces-sive dust emissions.

On the freeboard, activecorrosion was spot-blasted to SSPC SP-6 andsweep-blasted to SSPC SP-7.

On the topside superstructure, the areaswere degreased and cleaned with Proline® 747cleaner, an industrial degreaser used to cleanand etch the surface, and then rinsed with freshwater. “Etching helps to degloss the existingpaint to promote better adhesion of the newsystem,” Roulst says.

An area of particularly severe corrosionappeared under the aft platform and over thenet ramp where the trawl net towed behind thevessel is hauled aboard. This area was enclosedand sandblasted to SSPC SP-6.

Vent louvers were removed and sent throughTodd Pacific’s blast and paint facility, while someof the louvers that were rusted away to nothingwere replaced. Six trawl doors also were removedand sent through the blast and paint shop.

SPONGING OFFThe deck areas being prepared for polyurea

application were blasted to SSPC SP-10. Onthe decks, the crews utilized a Sponge-Jet® sys-tem because it creates very little dust emissionsand is more accessible in areas that containmachinery and other equipment.

“There are areas on our boat where, duringnormal fishing and offload activities, a standardcoating will be destroyed by the repeatedimpact of hard, heavy objects...”

“About half of the decks are being blastedby Sponge-Jet to SSPC SP-10, while theremaining half are being prepared by powertool on active corrosion spots followed by spotpriming and full topcoats,” says Judt.

“The blast pots we are using are small,hand-load types while the metering valve is asmall auger that feeds the sponge-impregnat-ed media into the high-pressure air streamwithin the blast hose,” Judt says. “This sys-tem may seem slow, but there is very littleequipment protection necessary compared to

conventional sandblasting.”Containment is very easy and can be

accomplished with simple tarping. “Dust pro-duced by the process is near zero,” Judt says.“The spent media doesn’t travel very far frompoint of impact so it can be easily cleaned up.The sponge media is re-useable, and we aresuccessfully using it several times over.”

EnviroLastic ® AL 450 SS polyurea wasapplied to approximately 7,100 square feet ofthe railings and steel decks of the AlaskaOcean. “About half of the decks were done,based on prioritizing areas according to themost severe duty and in accordance with timeand budget considerations,” says Judt.

One of the benefits of the 100-percentsolids, aliphatic polyurea coating system is itsrelatively slow gel time that enables smoothapplications at thicknesses ranging from 30to 250 mils, while providing a seamless, flexi-ble and waterproof coating solution that canbridge cracks to 1/8-in.

“This polyurea dries to touch in 30 sec-onds, stays a little soft for about two minutes,and can be safely walked on in about five min-utes,” says Judt, who notes that the crewsachieved 60 to 80 mils dft.

The polyurea application took place whileother repair and equipment installation crewswere working side-by-side on their respectivetasks. With a substantial number of craftsmenconcentrated into a small area, coordinationof the deck painting became a challenge.

“Time is almost never available,” Judt says.“Polyurea cuts the cycle time significantly andties in with ‘Lean Manufacturing’ methodsthat are currently sweeping the nation.”

Conventional non-skid deck coating sys-tems generally take three to four days to apply.As a result, the chances of damaging a freshlycoated surface increase with longer dryingtimes. According to Judt, the crews lovedusing the polyurea product because they wereable to apply the fast-drying coating and notworry about rework caused by adjacentrepairs, footprints, or rain.

“On one occasion, we painted a deck in aheavy downpour by building a tent to keepthe deck dry,” recalls Judt. “The fast curingnature of the polyurea was what we needed tosucceed, as conventionally cured coatingswould have been damaged.”

The polyurea was applied to decks wherefishing and offloading activities occur and

C O AT I N G S S O L U T I O N S / S P R I N G 2 0 0 414

A high gloss, UV-

resistant top coating

of Proline® 4800 in

Alaska Ocean

Seafood Blue was

applied to the free-

board.

frequently take a beating from crane hooks,steel blocks, shackles and huge, heavy nets,as well as trawl doors weighing several tonsapiece that mar the deck’s surface. The crewused a Gusmer SPI 18/18 proportioningunit, D type spray gun, and 16 KW genera-tor to power the heating units (pump andline) to maintain the 160 degrees F materialapplication temperature.

After learning about polyurea and theprocess at a National Shipbuilding ResearchProgram meeting, Judt became certified touse the special application equipment. “Ibrought the technology back to ToddPacific Shipyards and installed 40,000square feet on Todd’s dry docks duringwhich time I trained several of my crew,”he says, adding that dry docks are aneven more severe work platform thanfishing boats.

SINGLE SOURCINGBased on the maintenance require-

ments specified by the Alaska Ocean’sport engineer, the project incorporatedseveral other coatings. “One of our pri-orities was to have all of our coatings sup-plied from one source,” says Kaldestad, “sothat we didn’t have a problem trying to colormatch all the different coatings. Sherwin-Williams was able to meet all of our needs.In fact, we were even able to use one type ofprimer for the whole boat, which really madethings easier.”

Sherwin-Williams Seaguard® 5000 HSEpoxy was used on all parts of the boat. Theprimer provides an anchor for the newpolyurethane topcoat because of its excellentadhesive properties. “It also becomes part ofthe preservation barrier, keeping moisture andchlorides away from the steel and aluminumsurfaces,” Judt explains.

The company’s Corothane® Mio-Aluminum was used to spot prime specificareas on the superstructure. “This product hasa combination of two excellent barrier-build-ing pigments in a binder that enables it to curewell in humid conditions,” says Judt. “Weapplied it to specifically prepared spots as weworked through various areas.”

A topcoat of Seaguard® AblativeAntifoulant, an antifouling coating contain-ing cuprous oxide, was applied to the under-water hull. Recommended for the underwater

surfaces of steel vessels operating in all coastaland oceanic waters, the ablative antifoulantcoating maintains an effective, bioactive sur-face during its entire life and is formulated towear away (ablate) during vessel movement.

“It stops build-up of marine growth, whichin turn maintains ease of vessel movementthrough the water and ultimately improvesfuel consumption,” says Roulst, whose crewshandled painting the bottom of the boat. “Asmooth hull glides through the water with lit-tle impedance, compared to a roughly sur-

faced hull with shell growth.” A finish coat of Proline® 4800 in Alaska

Ocean Seafood Blue was applied to the free-board, while two coats of Prothane 4801 GlossWhite were applied to the superstructure.Both coatings are high gloss, UV resistant andoffer excellent color retention properties withno tendency to yellow in sunlight. While aes-thetically pleasing, the coatings exhibit superi-or abrasion and splash resistance to alkalis(salts), acids (nonoxidizing), and hydraulic flu-ids. In addition, they provide a slick surfacethat promotes moisture barrier and preventscontamination build-up.

“The UV resistance feature extends thetime it takes for the paint to ‘chalk’ or breakdown,” Judt explains. “This breakdown allowsmoisture to eventually migrate to the sub-strate. Moisture, particularly salt water,becomes an electrolyte upon the surface of themetal substrate that initiates rust formation.”

Now back at sea, the Alaska Ocean proudlysports her new coat, while her owners can restassured that their investment is being protect-ed from corrosive salt water and other causesof deterioration. “The men and women ofTodd Pacific Shipyard worked hard to give thisowner a high-quality product,” says Judt.

Sherwin-Williams

EnviroLastic® AL 450

SS polyurea was

applied to about 7,100

square feet of the steel

decks and railings of

the Alaska Ocean, pro-

viding excellent coat-

ing protection in high-

impact areas.

Vent louvers were

removed and sent

through Todd Pacific’s

blast and paint yard.

S P R I N G 2 0 0 4 / C O AT I N G S S O L U T I O N S 15