In-air rebuild saves time and money

The 2007 season forecasts for the asphalt industry look to be promising. More commercial and state work will be available, along with plenty of residential jobs. The prospect of an exceptionally good season has hot mix asphalt (HMA) producers all across the country gearing up for what is hoped to be a breakout year.

At Flynn Brothers Paving, the feeling is much the same; optimism is palpable. “We believe that this next season is going to be a good one for us, so we have prepared ourselves for it,” states Butch Rogers, superintendent.

One way of preparing for a busy season is to improve a facility so production can be maximized. “Increasing production can be accomplished in several ways—new equipment, used equipment or by reconditioning what you have. Enhancing your plant does not always require purchasing new equipment. It can also mean improving what you already have in place,” says Charles Grote of Reliable Asphalt Products, Inc., a major supplier of asphalt plant equipment and services.

Flynn Brothers Paving is a large HMA producer in the Louisville, Kentucky, area and they are routinely the go-to producer for many paving companies. Flynn realized they needed to rebuild their main drag-slat conveyor at their Robards Lane facility. “Our main drag conveyor was antiquated and badly needed to be repaired. We needed to increase its capacity and reduce the maintenance load on this particular piece of equipment,” stated Rogers.

Flynn has been steadily improving this site, their main plant, over the last few years due to its ever increasing demand. According to Rogers, “We needed to upgrade something every year.” The original plant was a lower production Standard Havens Parallel Flow drum plant before it was replaced with an E500 Cedar Rapids drum plant. Along with the new plant, Flynn added a vertical asphalt storage tank, a baghouse and two silos.

As Flynn’s plant puzzle was put together, the one remaining piece to fit in place was the drag-slat conveyor. “We needed to upgrade the slat and we needed some good suggestions,” said Rogers. The suggestion Rogers received was reconditioning. Faced with rebuilding the conveyor, Reliable Asphalt Products was eager to jump at the chance.

Unique Requirements
Like most contractors in this business, Flynn Brothers had budgetary concerns. Knowing this, the supplier approached Rogers with a unique proposal. “The idea was to totally recondition the drag-slat conveyor, not in a shop, but in-place while they were in a shut-down mode during the winter months. This would save downtime and excessive transportation costs,” stated Grote.

Rogers was receptive to the in-place re-build idea. From years of retrofitting experience, he knew that the costs of removing a slat conveyor and reconditioning it off-site could be exorbitant. Instead, the reconditioning materials were brought directly to the Flynn plant. “The last time we did something like this, renting the crane cost $20,000. So working on it while it was still in-place saved a tremendous amount of money,” explained Rogers.

What Needed to be Done
Originally the conveyor was on the lower production plant, and it required additional capacity in order to accommodate higher production rates. “That drag used to be on our Standard Havens 250 tons per hour plant. The first thing we had to do was speed it up to run the E500. The slat had a 50 horsepower drive unit that we changed out to a 100 horsepower drive unit to run this plant,” explained Rogers.

The hardest part of the complicated reconditioning process was replacing the old floor and sideliners of the conveyor. Reliable’s crew worked diligently to remove the heavy dual, 4-inch pitch chain while Flynn’s crew did some of the work on the shaft and take-ups. Reliable was responsible for replacing the floor. “We split it up and did it in three sections. The entire floor was pretty wavy, creating a bumping effect from the chain hitting the uneven surfaces. We removed the old floor, leveled it and bolted in new chrome carbide plating the entire length of the slat, with welded-in side walls. This upgrade, coupled with the larger drive, enabled Flynn to produce at a higher rate—and, just as importantly, reduce maintenance,” said Charles Grote. “The new drag works perfectly and the whole job saved us a ton of money,” said Rogers.