The Fleet Business Authority
Issue link: http://heavydutytrucking.epubxp.com/i/236631
Maxion Wheel, says corrosion pitting is metal from the wheel that has been eaten away. He advises caution when working with deeply pitted wheels. "When you take off layers of corrosion, you're taking some base metal away from the wheel," he says. "If you go too far you can weaken the wheel." With the wheel stripped clean of previous coating material and rust, it should be handled with gloves, not bare hands, to prevent oils from contaminating the surface. The bare metal should be promptly recoated to minimize contact with moisture. Some processes apply a primer coat, while others paint directly or use an electro-static coating. Pricing can vary with the type of coating used and the quality. Application of the final coating is critical, Redding says. "The coating cannot be any more than 3 - 3.5 millimeters thick, especially on the mounting surfaces and between the bolt holes," he warns. "Excessive coating thickness can lead to a loss of clamping force and eventually loose "When you take off layers of corrosion, you're taking off some base metal of the wheel. If you go too far you can weaken the wheel." – Mark Fonte, Maxion Wheel nuts and possibly a wheel loss." Depending on the coating, curing can produce better results than air drying. It's just another part of the process than can add cost. There are gauges for measuring coating thickness, and Fogal recommends fleets audit their suppliers from time to time. "This is a hot topic for fleets," he notes. "They want to be sure that the vendor is using a coating designed for a harsh environment that meets certain corrosion-resistance thresholds, not just an off-the-shelf paint you'd use on a filing cabinet, and that it's properly applied and cured." Swabbing the wheel with acetone or methyl-ethyl-ketone can ensure it was properly cured. Uncured paint will come off on the swab. A properly cured coating will not. Folweiler says Wilson trucking began refinishing its own wheels in 1993. Once a wheel has been shot blasted that many times, it would be wise to mic the wheel just to be sure it's still structurally sound, he advises. "I'm not sure how many, but I know we still have some wheels in service that date back to 1993 when we started doing out own refinishing," he says. "That has been a tremendous ■ savings for us." Information sources for wheel inspection and refinishing • TMC Recommended Practice RP 240 gives a comprehensive overview of the proper refinishing procedures. • TMC Recommended Practice RP 222C contains wheel inspection criteria and procedures. • Accuride Service Guide W4.000 "Wheel Out-of-Service Guide" helps identify common wheel defects with illustrations. • OSHA regulation 3086, "Servicing Single Piece and Multi-Piece Rim Wheels" outlines wheel inspection criteria and out-of-service conditions. Circle 152 on Reader Action Card www.truckinginfo.com JANUARY 2014 • HDT 53