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less water than wet or slurry technologies, according to manufac- turer's spec sheets. e low-dust blast allowed the crew to forgo bulky and heavy hooded air-fed respirators in favor of face shields and half-face respirators, which helped prevent fatigue. No one wants to feel completely beat at the end of the day. Working from Genie and JLG Industries telescoping boom lifts, the crew attacked the tanks with 150- to 200-mesh abrasive media by UniWest called Star Bright. To maximize production rates, the blast men used #8 round tips and held the nozzles about 18 inches (457.2 mm) from the surfaces at 60- to 90-degree angles. "Star Bright is pretty fine stuff," said Rein. "We originally tried regular silica sand but needed more consistent-sized media to get better production. Star Bright's designed for mill scale and does the trick in a hurry." Beet Flash Rust To help beat flash rust, the crew added HOLD*BLAST by CHLOR*RID to the EcoQuip's water tanks at a 50:1 ratio. Running the anti-rust agent through the vapor blasters saved time compared to spraying HOLD*BLAST onto each tank after blasting. It also gave the crew breathing room between the blast and the basecoat application. "HOLD*BLAST gives us leeway on getting the primer down," said Rein. "If you don't use it, literally as soon as you're done blasting and the water evaporates, rust starts showing. Using it allowed us to apply the basecoat up to three days after the blast." Mascoat's insulating coating self-primes over non-fer- rous metals, such as aluminum and stainless steel, but these carbon steel tanks required International 's Intertherm 228 HS basecoat. Intertherm 228 HS is a two-component, high-build epox y specifically formulated for use beneath thermal insula- tion coatings (TIC). Working w ith afternoon air temperatures hovering around 100° F (38° C), 228 HS offered an operational pot life of about an hour, according to Rein, who did much of the spray ing. His go-to rig for the 228 HS was a Spray Tech airless w ith 519 tip. "We were aiming for 4 to 6 mils [101.6–152.4 microns]," Rein said. To achieve that dry film thickness (DFT), Reins and his crew crosshatched the spray using horizontal and vertical sweeps. "We weren't overly concerned about putting down too much material — 8 mils [203.2 microns] would have been okay — but we definitely didn't want any spots with just 3 mils [76.2 microns]." For a thickness check on the fly, the coatings applicators found that when they applied enough 228 HS so that they couldn't see base metal, they were right around 4 mils (101.6 microns). T he crew sett led into a productive routine w ith t wo men vapor blasting , t wo apply ing coatings, and t wo f i l ling in. T hey were c law ing their way to get back on track w ith the dead line. But the tr ick iest par t of the application was sti l l to come, and factors beyond their control threatened to g ive this crew a rea l beat dow n. Since the tanks hold beet juice at a various temperatures, insulation needs varied. erefore, the tanks were specified to receive three different total dry film thicknesses of 228 HS: approximately 60 mils (1,524.0 microns), 90 mils (2,286.0 microns), and 150 mils (3,810 microns). at meant on average between three and eight coats per tank at 15–20 mils (381–508 microns) DFT per coat. at also meant a great deal of time allotted for curing between coats. With no time to lose, the ERIC crew fired up their Graco GH 833 Big Rig sprayer. "We sprayed the DTI just like the Intertherm, crosshatching, but unlike the primer where we didn't mind going a bit heavy, we didn't want to put down too much DTI," said Rein. "Any single coat over 30 mils [762.0 microns], we felt there might be a risk of trapping moisture inside and not getting a full cure." 58 SEPTEMBER 2016 COATINGSPROMAG.COM Tank Insulation Coating VENDOR TEAM Capital Safety Safety equipment manufacturer 3833 Sala Way Red Wing, MN 55066 (800) 328-6146 www.capitalsafety.com CHLOR*RID International, Inc. Material manufacturer P.O. Box 908 Chandler, AZ 85244 (800) 422-3217 www.chlor-rid.com General Tools & Instruments Equipment manufacturer 75 Seaview Dr. Secaucus, NJ 07094 (800) 697-8665 www.generaltools.com Genie Equipment manufacturer 18340 NE 76th St. Redmond, WA 98052 (800) 536-1800 www.genielift.com Graco Inc. Equipment manufacturer 88 11th Ave. NE Minneapolis, MN 55413 (612) 623-6000 www.graco.com Guardian Fall Protection Safety equipment manufacturer 6305 S 231 St. Kent, WA 98032 (800) 466-6385 www.guardianfall.com International Paint Coating manufacturer 6001 Antoine Dr. Houston, TX 77091 (713) 683-1711 www.international-pc.com JLG Industries, Inc. Equipment manufacturer 1 JLG Dr. McConnellsburg, PA 17233 (717) 485-5161 www.jlg.com Mascoat Coating manufacturer 4310 Campbell Rd. Houston, TX 77041 (800) 769-0233 www.mascoat.com Spray Tech Systems, Inc. Equipment manufacturer 1025A Enterprise Ave. Oklahoma City, OK 73128 (800) 777-7729 www.spraytechsys.com UniWest Material distributor 6201 E 42nd Ave. Denver, CO 80216 (888) 728-9120 www.unitedwesterndenver.com