From rail to sail: Aggregates distribution
February 1, 2008 By: Carol Wasson Pit & QuarryA major rail-based distribution network beefs up material handling to meet growing customer demand.
Rail-based aggregate distribution is on the rise. In fact, a recent Florida-focused report refers to efficient rail transport as "the linchpin" behind the rapid movement of material from mine to market. The study states that Florida's current pool of 4,000 railcars must be increased to handle the additional material coming from out-of-state stone quarries and through port terminals that need redistribution by rail.
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Headquartered in Daytona Beach, Conrad Yelvington Distributors Inc. (CYDI) is the largest rail distributor of aggregates in the southeast region of the United States, moving more than 10 million tons of material annually through a network of 29 rail-served distribution terminals in Florida, Alabama, Mississippi and Michigan. The company currently leases more than 1,800 hopper cars, and owns and operates at least 35 locomotives. Its rail logistics department communicates with CSX Transportation personnel and is linked to the CSX computer system for up-to-date information on rail shipments and railcar locations. Most terminal sites offload one to two 60- to 100-car unit trains each week, with each railcar holding up to 100 tons of material.
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Aptly put, the CYDI slogan is "aggregates in motion," a phrase that fits its rail distribution network as well as the ongoing material handling upgrades at its terminals – the latter being an initiative toward greater stockpiling capacity and efficient unloading at lower costs per ton. To that end, CYDI has recently installed no less than a dozen automated telescoping radial stacking conveyors and at least five automated truck unloaders, all manufactured by Superior Industries. The new material handling equipment is placed in a number of terminals and applications, with plans for even more units being added as new terminals open within the network. At certain sites, Superior Industries has also engineered the tunnel conveyors and overland conveyors for the transfer of material from the railcars to the telescoping stacking conveyors.
When a 100-car train arrives at the company's DeFuniak Springs terminal in Florida, the train splits onto five different tracks. A locomotive backs in and hooks onto one of the sections at a time, pulling each car over the tunnel conveyor where its load is conveyed to the telescoping radial stacking conveyor, which builds up to eight different product stockpiles on the site's main part. Then the telescoping conveyor is remotely adjusted to feed its load onto a 300-ft. overland conveyor. This conveyor transfers material to an additional yard, which accommodates another eight high-volume stockpiles. The entire 10,000-ton shipment takes about 10 hours to unload and stockpile, all without the use of a loader or truck.
 Here a haul truck is shown unloading material onto the automated Superior RazorTail truck unloader. |
Pump up the volume
CYDI distributes a variety of materials including granite, limestone, decorative stone, river gravels and silica sands. No matter what the material, the company's goal is to maximize stockpiling capacity at each of its distribution sites to meet growing demand. After all, regional reports indicate that from the mining process to the marketplace, and on to the placement of material at the construction site, less than a week may transpire. Therefore, unloading, conveying and stockpiling are key links in the logistics chain.
With more than 30 years of experience in the aggregate industry, Gary Yelvington is the president of CYDI. He cites several major reasons for replacing conventional stackers with the 42 in. x 170 ft. TeleStacker conveyors from Superior Industries. Top among them is up to 30 percent more stockpile volume on the same limited footprint.
"With the stinger conveyor on the TeleStacker unit, you can build a much larger volume pile than that built by a fixed stacker. You've got that extra length that you can run, and that makes a big difference in volume," he said, adding that an additional advantage is stockpiling without material loss due to segregation or degradation.
 Material is dumped from a railcar directly into the operation's surge tunnel. |
Minimized loader use is equally important. "With fuel, operator labor hours and the current tire situation, we need to cut our operating costs, and these conveyors allow us to do that," he said.
Then there is the issue of safety and loss prevention. "The safety in being able to adjust the telescoping stacker in bad weather is crucial. Once you retract the stinger conveyor, you bring the unit into a low profile," Yelvington said, explaining that they had lost a couple of conventional gantry-type stackers to high winds during the recent major hurricanes. "That's when we decided we had to make the switch to the TeleStacker conveyors. We can bring them in low to the ground, and we don't have all the cables to deal with, which was also a huge maintenance issue as well on the previous conveyors."
Effective truck unloading
Alabama offers more than 3,000 miles of railroad track serviced by five Class I railroads, which gives shippers excellent main line connections to all major market centers. CYDI currently maintains three rail-distribution terminals in the state, with a fourth under development.
At two of its Alabama sites, CYDI stockpiles and distributes petroleum coke (petcoke), a residual product of the oil refining process, which has made significant inroads into traditional utility coal markets. Particularly along the Gulf Coast, supplies of fuel grade petcoke are growing in response to the installation of new refining capacity. Petcoke is now being blended with coal for use in fossil-fuel power plants that can accommodate higher sulfur fuels.
 Material is dumped from a railcar directly into the operation's surge tunnel. |
The company's Calera, Ala., site is a coal and petcoke operation. "We've got a system there that blends coals with varying ash and sulfur contents to meet customer specifications. Then we stockpile it and sell it to the local market," Yelvington said.
Coal products are trucked into the site and unloaded. CYDI uses two Superior RazorTail truck unloaders to streamline its operations. The unloading systems can quickly and easily transfer material from belly dump trucks or end dump trucks and onto a conveyor.
"I have installed an infrared eye on the RazorTail. When the nose of the truck runs across the grate and dumps into the hopper, it breaks in front of that electronic eye, which automatically kicks the conveyors on," said Yelvington, who further explained that the system is equipped with a timer so that the belts will cut off after material transfer is finished. The system does not require a dedicated operator, nor does it require the truck driver to leave his cab to start the process.
Yelvington stressed the importance of the RazorTail being equipped with its own low-profile ramp. "Any other type of unloader would require us to pour a concrete tunnel and then install a conveyor within it. This system has everything you need – and it's portable – so if you need to, you can move it anytime you wish," he said, adding that he is combining the RazorTail with a 42 in. x 170 ft. TeleStacker conveyor to gain an even greater payback in product quality control and costs-per-ton savings.
Rail distribution growth
While trucks are still the prime movers of aggregate materials, rail is continuing to gain market share. Industry statistics show that more than 35,000 railcars serve the U.S. aggregate market today. Since 1982, CYDI has expanded from its initial single receiving locations to a unique multi-terminal aggregate distribution operation – and its addition of innovative material-handling systems is just one more way to fuel its growth to meet customer demand. .
Superior Industries Inc.,
www.superior-ind.com
Carol Wasson
is a veteran freelance writer for the aggregates and construction equipment industries.
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