When Ned Snead founded the Georgetown Rail Equipment Co. (GREX) in 1993, he was aware that technology was transforming the rail industry. That led him to invent the DumpTrain aggregate delivery system. It was a breakthrough in productivity, capable of delivering more than 2,000 tph of ballast with pinpoint accuracy using a single operator.
Ten years later GREX introduced a new innovation called Aurora. This 3-D track inspection system uses laser technology and state-of-the-art cameras to spot track and tie flaws before they cause costly problems.
Innovations like these have positioned GREX as the rail industry’s leading think tank. CEO William “Wiggie” Shell has more than 40 years of experience in the rail industry. He’s assembled a team of some of the best and brightest minds in the industry around him. Together, they continue to pursue the mission of creating real rail solutions that boost the safety and efficiency of track maintenance for their customers.
Today, GREX is a thriving company of more than 130 employees serving customers in North America and across the globe. “Our reputation has enabled us to partner with other industry pioneers to stay at the cutting edge and develop new technologies for our customers,” the company stated.
In creating the DumpTrain, GREX worked successfully with Van der Graaf, which has been manufacturing drum motors for the past 30 years in the United States and Canada.
“Our company is a service provider for the most part,” said Charlie Aaron, director of engineering for GREX. “We build trains of a specific type that are designed to deliver rock, then lease those to the railroads with an operator.”
“DumpTrain streamlines aggregate delivery so you can get in, get to work, and get back to freight or passenger operations in no time,” according to the company. Using a single DumpTrain, one GREX operating technician can unload aggregate at a rate of up to 2,000 tph – and do it with pinpoint accuracy up to 52 ft. from the center line of the track.
Material from each car is unloaded onto a single conveyor belt that runs the entire length of the train allowing for continuous delivery. That dramatic boost in productivity, efficiency and accuracy makes light work of even the heaviest delivery jobs and frees up crews to tackle more important tasks.
“Some people call it a belt train,” Aaron said. “It is a series of hopper cars with actuated gates to dump rock onto a conveyor belt. Each car holds roughly 100 tons of rock. We can configure a train of any length, but most of ours are configured for 1,500 tons, or 15 cars. When the car’s gates open, the rock falls onto the belt, and the belt carries it to the front of the train. At the front end of the train is what we call a stacker car – a car with a boom on it that can rotate a little beyond 180 degrees. It can unload onto stockpiles, or in windrows, but you can get the rock about 50 ft. from the track. Railroads use this very effectively to fill in a washout, for instance.”
DumpTrain was developed 25 years ago. “When it was developed, there was a single belt that ran the length of the train,” Aaron said. “But that didn’t operate on a curved track very well. So we developed the DumpTrain for Curves, which had an individual belt for each car.”
Each car in the DumpTrain for Curves variation is equipped with its own belt and drive system, allowing for material to be delivered to the preceding car all the way to the stacker. The result is a variation on the DumpTrain model that can distribute material evenly in curves. It also provides railroads with the flexibility to create custom-sized DumpTrains to suit the specific needs of individual projects.
The versatility of DumpTrain and DumpTrain for Curves lends itself to a wide range of applications:
FINDING A DRIVE PULLEY
“We were looking for a cost-effective drive pulley that would work with our cars. We didn’t have a lot of space to accommodate a pulley and gearbox, so we found a better solution: Van der Graaf Extreme-Duty Drum Motors,” Aaron said. “What appealed to us most was that everything was contained in an individual enclosure. Plus they were very price-competitive. This solution allowed us to have a more traditional design similar to our other hopper cars. It made the process more seamless and less difficult for us. Now we design cars with the Van der Graaf pulley in mind.
“What’s more, we used to have a single belt with a drive mechanism that pulled 1,000 ft. of belt, that’s a pretty hard task especially if there is rock on it,” Aaron continued. “That was made easier on the components with the Van der Graaf Extreme-Duty Drum Motors. They put a lot of torque into a small package. They were even able to customize a pulley for us.”
In addition to GREX’s fleet of standard DumpTrains, it currently operates multiple DumpTrains for Curves, and is building more to meet demand. Each of these has Van der Graaf Extreme-Duty Drum Motors on them. “This is a relatively new product for us,” Aaron said. “We went through several design innovations while we were in the testing phase. When we got to the final version, I can say that the product is very robust. We work in harsh environments and put a lot of demand on our equipment. We sometimes work in below zero temperatures, sometimes in 100-plus degree heat in Arizona. I can say that we have had zero equipment failures. Plus Van der Graaf Extreme-Duty Drum Motors are essentially maintenance free. That is a huge plus for us.”
Maintenance requirements for a drum motor are virtually zero, according to Van der Graaf. All of the components; electric motor, gearbox and bearings, are enclosed within the drive shell and bathed in oil, providing continuous lubrication. The only required maintenance is an oil change every 50,000 hours of operation.
“We’re constantly combining our products with other new technologies to provide new capabilities to customers,” Aaron said. “Our use of Van der Graaf Extreme-Duty Drum Motors is a perfect example of how we do that very successfully."
WHY A DRUM MOTOR?
The drum motor provides a number of features that are not typically found in conventional drive systems. By eliminating external components, a drum motor reduces the footprint of a conveyor drive, saving space. The reduction of components also results in a reduction of guarding requirements, making the drum motor a safer solution. With no external wear parts, a Van der Graaf drum motor requires only an oil change every 50,000 hours. Combined with an electrical savings of up to 30 percent, a drum motor provides a lower total cost of ownership compared to a conventional conveyor drive.
Stringent quality control procedures are followed; testing every unit for a number of operating factors at several points through the process, including stator performance, sealing systems pressure tests, as well as noise and vibration confirmations. All electric motors are wound in-house, including a vacuum pressure impregnation or VPI, of every stator to optimize their design for variable frequency drive use as well as in high-vibration environments. Van der Graaf is the only drum motor manufacturer to use this stator life-extending process on every motor manufactured.