In a landmark order, global equipment manufacturer Astec Industries has supplied and commissioned the first Astec (Roadtec) cold planer on the important N5 corridor maintenance and rehabilitation project in the Free State.

The group reports that it is proud to be contributing to SANRAL’s critical national infrastructure improvements after supplying an Astec (Roadtec) RX-600ex 2.0m Cold Milling Machine to Damian’s Contractors, for use on the roadworks between Bethlehem and Harrismith.

This is the first deployment of an Astec RX-600ex (Roadtec) cold planer in this part of South Africa. The order is also significant because this is one of the first demo-to-direct sales of this model by Astec Industries’ South African Infrastructure Solutions division.

The high visibility of the site and the often-heavy traffic volumes on the N5 corridor demand precision milling, speed, efficiency and uncompromising safety. The Astec RX-600ex has got what it takes to exceed expectations, comments Philip Saunders, product sales manager for Astec Industries’ Materials and Infrastructure Solutions divisions.

Smooth and uniform roadways

Cold planing, also known as asphalt milling, is the removal or milling up of an asphalt surface to provide an improved surface for repaving or resurfacing. It ensures smooth and uniform roadways.

Powered by a 630 horsepower Cummins QSX 15Tier III engine, the Astec RX-600ex has a 2007 mm wide QX1 asphalt milling drum with 16 mm tool spacing. Its key features include a dust extraction system, hydraulically folding conveyor, Astec’s ACE Grade & Slope Automation with auto-cut entry, dual water spray bars and bolt-on track pads – all of which are standard on the machine. It also boasts an Astec QX1 quick change cutter drum, integrated dual operator platform with simplified intuitive controls and dual water spray bars.

Saunders explains the benefits of these features: “A standard dust extraction system improves operator comfort and safety by removing dust and debris from the milling operation through a hydraulic fan at the primary conveyor. The dust is ejected at the end of the secondary conveyor into the dump truck. As the dust is ejected, the material exiting the secondary conveyor belt helps to channel the fine material into the dump truck.

“The folding secondary conveyor available on the Astec RX-600ex as ‘standard’ simplifies transport and loading. A boost function, also offered as a standard feature on the machine, temporarily speeds up the conveyor should it become overloaded.”

Improves access

He notes that the cold planer’s Astec QX1 cutter drum improves access for bit and insert removal.

Astec cold planers like the RX-600ex have two independent spray bars to inject water in the cutter housing. The front spray bar is primarily for dust suppression. The rear spray bar cools the drum.

The ACE system enables the automatic calibration of specific hydraulic parameters - ensuring that the machine consistently achieves the precise milling depth, while the grade and slope sensors maintain the prescribed parameters when in full operation. New graphic displays allow the milling crew to easily select, calibrate and control sensors with minimal time and effort. The ACE Auto-Cut Entry system automatically controls the drum's depth when initiating a cut, rather than requiring the operator to do so manually. It ensures that the drum connects with the pavement at the required depth and angle for the milling task.

This machine’s operator platform is conveniently accessed from the right or the left side. Two control stations allow machine operation from either side. With multifunctional joysticks and accessible controls, operating the cold planer is clear and intuitive. The controls are designed to be operated with one hand to allow for truck signalling.

Saving road builders time and money

“When your track pads are ready to be replaced, you can simply unbolt the old ones and bolt on new ones, saving road builders time and money,” Saunders notes. Because the bolts are not exposed to the surface, there is also the benefit of no asphalt build-up. “Traditional track pads utilise ‘through bolts’ which build up with asphalt and take longer to remove and replace.”

The RX-600ex is part of Astec’s expansive Rock to Road range, which includes equipment for every phase of road building - from quarrying, crushing and processing the aggregate to concrete production and road construction. High-performance, fuel-saving machines like the Astec RX-600ex are ideally suited for infrastructure programmes in Africa. Like all the equipment in Astec’s range, the RX-600ex is supported by Astec’s skilled team in South Africa, which offers commissioning, training and aftersales service, support and spares.

Saunders says that the factors that contributed to Astec netting this order from Damian’s Contractors included the immediate availability of the machine and its suitability for the project, including its advanced automation (ACE) system. In addition, Astec was committed to ensuring the seamless commissioning of the machine and offering training.

Among the challenges that Astec rose to were the tight project timelines, accommodating public road traffic and training the crew on advanced automated milling systems. In addition, the machine had to be commissioned and handed over under testing, live working conditions.