On the Fast Track
Effective Material Handling Meets High-Volume Delivery & Stockpiling Goals at Rail-Based Distribution Center
The state of Georgia is investing $200 million into two I-75 lane widening projects in Cook County. Governor Sonny Perdue is accelerating the initiative as part of his Fast Forward Program, which expedites economic development and congestion mitigation transportation projects. Vital for commuters, commercial truck traffic and tourists, I-75 is considered by the state’s leadership as a lifeline to continued growth, new business recruitment and new jobs. As such, the projects have been placed on the fast track.
Scheduled for completion in December 2009, the Valdosta-headquartered Scruggs Company, Inc. is performing the work, which includes some 20 miles of widening to six lanes with a paved shoulder, and the reconstruction of five bridges and approaches.
With the two projects came the potential aggregate requirement of over 2 million tons, a statistic that spurned some serious strategizing on optimum material delivery and stockpiling methods. The solutions would lie in cost-efficient rail transportation to a geographically-desirable and newly created distribution center, which would supply an onsite asphalt plant and two portable concrete plants on a site ten miles from the center.
Scruggs Company consulted with Morris, Minn.-based Superior Industries as to the unloading and stockpiling systems, which would be designed to minimize or eliminate loader use, while preventing material segregation.
In short, the Scruggs Company distribution center is supplied by a dedicated 50- to 60-car unit train. Each railcar is a bottom-discharge unit which unloads into a surge pit, with material being fed to a 240-ft Superior overland conveyor, which then feeds an automated 190-ft Superior TeleStacker Conveyor for fully or partially desegregated, high-volume stockpiling. “The unloading of single-size stone from the entire unit train (5000 to 6000 tons) can be completed in six hours,” says Scruggs Company General Manager Mike Fisher.
Importantly, it is the combination of effective rail transportation with customized material handling technology that allows the company to meet its production goals. After the I-75 projects are completed, the distribution center will serve additional projects, ensuring that the company will maintain or expand market share in the region.
Cook County, Georgia
In 2009, Scruggs Company was awarded the I-75 lane widening project where over 2 million tons of aggregate were required. To optimize material delivery and stockpiling methods, the company used rail transportation to supply an onsite asphalt plant and two portable concrete plants. Railcars with a bottom-discharge unit unloaded into a surge pit, with material being fed to an overland conveyor, when then fed an automatic 190-ft TeleStacker Conveyor. The combination of effective rail transportation with customized material handling technology allowed the company to meet its production goals.
Rail vs. Trucking
“Rail transport helps to profitably handle our jobs. We have close to 50 trucks in our fleet, so we know how much it costs to truck materials. If you divide 2-million tons of material by a 23-ton truckload – that will tell you how many truckloads would have to come down that interstate for these projects. We knew that we would have major difficulties getting that material in by truck. Rail is safer and more economical,” says Fisher.
If one does the math as Fisher suggests, it would take nearly 87,000 truckloads of material to service the projects.
As of the year 2000, trucking accounted for more than 83 percent of crushed stone transportation, while rail supported less than 8 percent of shipments. However, current market pressures are behind a significant increase in the use of railway transport today.
While the cost per ton-mile of unit-train transport is close to one-third of the ton-mile cost of trucking, rail transport requires a facility cost and specialized equipment. So one’s production volume must increase in order to be profitable in the rail mode. With the need for a 2-million-ton shipment of aggregate, the Scruggs Company projects are an ideal application for rail transport.
Establishing Based Support
The Scruggs Company distribution center is located in Lenox, Georgia, with shipments arriving from its quarry in Macon, approximately 125 miles away. The facility is served by a main Norfolk Southern rail line that feeds from the north, and all the way into Florida. “It’s one of the busiest lines in the nation. We have a turnout off that line which allows the train to pull right into our yard,” says Fisher, adding that they have a dedicated train which carries nothing but their stone. “Once we unload, the train returns to Macon,” he says.
As to the processes involved, Fisher explains, “We hired a railroad engineering firm that designs railroad spurs and tie-ins. They worked closely with the railroad as to the location of the turnout, the sidetracks, and the surge pit. Then we talked with Superior Industries about space requirements, and material unloading and storage goals. With all that coordinated, we put a mass plan together. The engineering firm completed the track work. Our staff erected the facility, and Superior Industries was right there with us from installation through startup. We never felt like we were alone with a product. This gave us a lot of confidence, especially since this was our first distribution center.”
The center became operational in January of 2006. “From start to finish, the project took ten months, including approvals. The railroad must approve everything you do, including the specs of the surge pit,” says Fisher.
Creating Customized Material Handling
At the heart of the new distribution center’s material handling system is an automated 190-ft Superior TeleStacker Conveyor, the largest in the series, and fully programmable to build partially or fully desegregated stockpiles. It’s well-suited to the distribution center’s needs which require multiple, high-volume stockpiles.
Notably, a stockpile built by a telescoping radial stacking conveyor will comprise approximately 30 percent higher volume than that built by a conventional conveyor, as the axle on a telescoping conveyor is placed closer to the feed point. Because the stinger conveyor is able to retract, the operator is able to stockpile back to the axle. Also, the unit can be programmed to create stockpiles of many different shapes, sizes and configurations, while allowing the operator to easily switch from one stockpile to another.
“We know that the TeleStacker Conveyor is the best way to go. It does exactly as projected. We like the fact that the unit is easy to program and maintain, and is very user friendly. It’s seamless in operation,” says Fisher.
into the future
Eventually the Scruggs Company may employ an automated TeleStacker conveyor system at other facilities, says the company. “We know that there is a savings in unloading 50 to 60 cars once a week versus the ten-car-per-day service typically available at older facilities. Next, without a TeleStacker Conveyor, we handle the material twice as much, and we wear out our loaders twice as fast. And, there is the cost of maintaining a staff for unloading and stockpiling each day,” says Fisher.
Scruggs Company is realizing the benefits of rail transport and automated material handling. “We understand the value of putting in a unit train facility, and with the automated TeleStacker Conveyor, we knew we would save money. We’ve seen what this can do to get material in at a cheaper price,” says Fisher.