ForConstructionPros.com

It's hard to imagine a piece of equipment that works harder in tougher conditions than a pavement mill. These tireless machines grind away all day long under load, at times removing more than a foot of asphalt as they trudge ever forward. In the process, they're generating debilitating heat and abrasive silicon dust, all potential roadblocks to performance and productivity.

So how does one maintain a machine that cost anywhere from $300,000 or more for intermediate models to upwards of $500,000 and beyond for high-production models? How does a pavement contractor optimize its performance so a project stays on schedule? The answers lie within a rigorous preventive maintenance program and daily inspections.

"We recommend that contractors clean, lubricate, and inspect their machines at the end of every day," says John Hood, manager of product development and sales for Bomag Americas paving products located in Kewanee, IL. Bomag manufactures five pavement milling machines on 300- and 600-hp platforms. The 300-hp platform features models with 24-, 40-, and 48-inch drums.

Hood notes that by completing daily maintenance at day's end, most any repair issue discovered during inspection can be rectified prior to starting the project the next morning. The evening maintenance regimen, he adds, should begin with a thorough washing – with special attention given to the cutter drum and both the top and bottom conveyors. "The drum works like a garden tiller, except instead of cutting through soil it is cutting through asphalt," Hood says. "Maintenance personnel should check the cutting tools to make sure that none are broken and that they're wearing evenly and then inspect the spray bars to make sure the tips are not plugged. The spray bars both lubricate and cool the tools and if they're plugged, operators will likely burn up cutting tools."

After pressure washing the conveyors, he advises contractors to slowly turn the belts to inspect them for tears or other imperfections. "It takes anywhere from four to six hours to replace a belt," he adds. "Again, contractors would rather take the time to make the repairs at the end of the day rather than be forced to replace the belts when they should be milling."