APAC Paves US 51 with a Smooth Screed
BY Wirtgen Group
On a 10-mile stretch of US 51 in Holmes County, Mississippi, APAC Mississippi used its new Vögele VF600-3 screed from Wirtgen America, headquartered in Nashville, Tennessee, to get a smooth finish along some varying paving widths. Here’s how they did it.
Mounted on the Vögele Super 2003-3i paver, the VF600-3 is the latest generation of front-mounted extending screeds developed for the 10-foot highway class pavers. New electric screed heating developments have reduced the time required to reach working temperature, reducing APAC Mississippi’s start up time and offering them even distribution of heat along the screed plates.
“This stretch (of road) has a lot of driveways and turnouts for fields, so we ran the end gate in and out a bunch,” Fred Course Jr. said. He’s a screed operator for APAC Mississippi. “The controls and hydraulics are smooth, giving us a good-looking job.”
The crew was paving 12 feet wide and 1.5 inches thick to overlay US 51 with a 9.5-mm Superpave mix. The stretch of road Course Jr. referred to was between Pickens and Durant, Mississippi. They used the telescoping system on the VF600-3 screed, which offers paving widths of 6 feet to 25 feet, 5 inches, to extend from 12 feet to just a little wider as they encountered drives and turnouts. Using a single tube system, even at maximum extension, means half of the three-part telescoping tube is clamped; this design is to ensure optimum stability. The elevated location of the system also prevents contact with the asphalt mix.
Course Jr. continued, “Cleanup is easier with this new screed since the (auger) sensors automatically give the extension the amount of mix it needs, and the (telescoping) tube is up out of the way.”
Course Jr. shared some of the crew’s best practices. “Before we get going, I zero out the tow point and add a ½-inch of attack. Then all we need to do is adjust the end gates in and out. There is no better mat, just look.”
To ensure a smooth ride, APAC Mississippi equipped their Vögele 2003-3i with the Big MultiPlex Ski option and Niveltronic Plus for automated grade and slope control. The latest version of the Big MultiPlex Ski is designed to be set up completely in just seven minutes. Its 16.5-foot to 42.5-foot beam can be fitted with three multi-cell sonic sensors as standard—or up to five if required. This enables the Big MultiPlex Ski to scan several reference points along the length of the beam. Vögele’s Niveltronic Plus system for automated grade and slope control calculates a mean from the measurements taken across the entire measuring range, making up for any unevenness over long distances. In this way, the system offers APAC Mississippi greater precision than an individual single-cell or multi-cell sensor.
Jim Holland, vice president of sales for Vögele in North America commented, “APAC Mississippi invested in bringing their paving crews to Nashville to see and experience the Super 2003-3i with the VF600-3 screed firsthand before making a buying decision. After speaking with our product experts and operating the equipment on our demo grounds, the crews better understood the thought and engineering that goes into our pavers that make it easier to operate and provides superior productivity.”