CoatingsPro Magazine

NOV 2017

CoatingsPro offers an in-depth look at coatings based on case studies, successful business operation, new products, industry news, and the safe and profitable use of coatings and equipment.

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COATINGSPRO NOVEMBER 2017 45 would have been applied in two passes to reach the DFT. Greer worked with the F. Roberts crew closely at first to make sure the application stayed on spec. Together, they found it best to vary spray pressures between 20 and 80 psi (137.9– 551.6 kPa), using lighter pressure on new steel and heavier on thickly rusted areas to ensure coverage and penetration. "It has just enough coloration and wet look that you can clearly see what you did and didn't hit," said Stofle. "e speed at which the visible change takes place is fantastic. Most of the time, 15 minutes later, you can double back down for a second coat if needed. We're not spot checking with WFT [wet film thickness] gages here. With the low cost of material, it's faster and cheaper just to hit an area again. By the time you got done checking with a gage, I could respray the entire room again." On horizontal wear surfaces, the crew allowed the CRS to cure 4 to 5 hours before applying two passes of C2M direct-to- metal cement to achieve approximately 4 mils (101.6 microns) total DFT. Working out of 5-gallon (18.9 L) buckets, the F. Roberts crew began rolling and brushing the C2M. "We prefer rolling," said Stofle. "Some of this delaminated steel looks like solidified lava, and the heavier nap [¾ inch, 1.91 cm] rollers give good penetration. Our technique is pretty much pour and roll. If you're too conservative with C2M, you wind up spending more time trying to force it into nooks and crannies than is worth- while. Better just to pour it naturally and let the steel take it. en you just pull the coating back and you're done." In tight areas where rollers couldn't reach, the men used the traditional dip and brush method. roughout all stages, the crew wore hard hats, orange safety vests, and steel-toed footwear. ey were also sure to wear safety glasses, gloves, hearing protection, Ty vek suits, 3M dust masks, and 3M organic vapor cartridge respirators as required. Stem the Tide roughout this ongoing project, the F. Roberts team has triumphed in their battle to stem the tide against corrosion. Depending on the porosity, the crew spray applied one or two passes of MAXON's CRS anti-corrosive primer. On horizontal wear surfaces before roll and brush applying two passes of C2M direct-to-metal cement. JOB AT A GLANCE PROJECT: Spray, roll, and brush apply anti-corrosion boundary layer aboard the long-neglected Queen Mary COATINGS CONTRACTOR: F. Roberts Construction, Inc. 19300 Hamilton Ave., Ste. 100 Gardena, CA 90248 (949) 689-6711 www.frobertsconstruction.com SIZE OF CONTRACTOR: ~45 fulltime workers SIZE OF CREW: 15 crew members PRIME CLIENT: Urban Commons 777 S Figueroa St. #2850 Los Angeles, CA 90017 (213) 260-9111 www.urban-commons.com SUBSTRATE: 85-year-old steel CONDITION OF SUBSTRATE: Ranging between fair to beyond repair SIZE OF JOB: ~1 million sq. ft. (92,903.0 m²) DURATION: Ongoing 5-year project UNUSUAL FACTORS/CHALLENGES: » The ship functions as a hotel with restaurants, shops, and meeting spaces, so abrasive blasting wasn't an option. » Decades of neglect below decks resulted in massive rust, flooded compartments, and tons of debris. MATERIALS/PROCESSES: » De-watered flooded compartments » Shoveled, hauled out, and scrapped nearly 80 tons (72.6 metric tons) of corroded steel debris » Blasted with high pressure water where possible to descale rust » Removed flaking rust with hand and power tools where water blast wasn't possible » Spray applied commercially available degreaser; wiped and rinsed » Spray applied 1–3 mils (25.4–76.2 microns) dry film thickness (DFT) in one or two passes, depending on substrate porosity, of MAXON Technologies CRS anti-corrosive penetrating primer » Rolled and brush applied two passes of ~4 mils (101.6 microns) total DFT of MAXON C2M direct-to-metal cement on horizontal wear surfaces SAFETY CONSIDERATIONS: » Held daily pre-shift safety briefings » Wore hard hats, orange safety vests, and steel-toed footwear at all times » Wore safety glasses, gloves, hearing protection, Tyvek suits, 3M dust masks, and 3M organic vapor cartridge respirators as required

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