Caterpillar road reclaimers adopt cold planer rotor drive

The 762 gross hp RM800 utilizes twin turbochargers to deliver up to 23% more power than the RM600. (Photo: Caterpillar)

Caterpillar has rounded out its reclaimer/stabilizer product family with the addition of the RM600 and RM800, both of which are situated at the high end of their size class and are powered by high-horsepower Cat C18 industrial diesel engines. The models are also equipped with a new rotor drive system and an all-new adjustable height design that enables cross-slope cutting.

The RM600 and RM800 join the lower-horsepower, lighter weight RM400 and RM500B, with the RM600 offering a maximum operating weight of 79,397 lb. and 636 gross hp, and the 75,722-lb. RM800 providing 762 gross hp. The C18 inline 6 engine utilized in the two new machines has bore and stroke dimensions of 5.7 in. x 7.2 in. and a displacement of 1104.5 cu. in. It delivers the power to cut 96 in. wide at up to 20 in. deep.

“The RM600 uses a single turbocharger delivering up to 17% more power than the RM500B, while the RM800 utilizes twin turbochargers to deliver up to 23% more power than the RM600,” Mark Eiden, global sales consultant for rotary mixers at Caterpillar, noted. “A single electronic control module monitors engine performance and provides diagnostics to the operator.”

The engines are paired with an efficient cooling system that uses cool air intake to maximize fuel efficiency and reduce emissions. “Reversible cooling fans automatically perform periodic cycles in reverse to clean the heat exchangers. This allows the system to cool more efficiently, ensuring that the engine is working optimally and [extending] cleaning and maintenance intervals,” Eiden said.

Two configurations of the C18 are available to meet regional emissions requirements.

Common components with cold planers

The new rotor drive system found on the RM600 and RM800 may look familiar to those who know Caterpillar cold planers.

“The robust rotor drive system utilizes components common with Cat cold planers,” Eiden said. “It’s a real step change from our current RM400 and RM500B. Those are direct-drive rotor drive systems where we take the power from the engine and drive directly with heavy chains to the rotor. But to get this higher horsepower class to satisfy the demands of sometimes 12 or 14 in. of asphalt to reclaim, we use a belt drive system similar to our cold planer product.”

The RM600 has a 636 gross hp C18 engine with a single turbocharger that enables 17% more power than the RM500B. (Photo: Caterpillar)

The rotor drive system incoporates an adjustment-free, hydraulically actuated heavy-duty drive clutch plus two high-tensile strength six-rib drive belts with a hydraulic belt tensioner to prevent slippage.

“Using a belt-driven rotor drive system provides clearance on the right-hand side of the machine for flush cutting capability,” Eiden said. “The RM600 allows you to select all six rotor speeds without ever leaving your seat. The RM800 has a range of six speeds within each pulley position for a total of 12 speeds.”

The planetary gear drive in the rotor is robust enough to handle the heavier cuts demanded of these machines, he added.

The RM600 and RM800 also come with the newly designed K rotor, which again uses fastener-free, dual-taper toolholder and base block components from the company’s cold planers.

“The rotor has been designed using common parts from our successful cold planer system K rotors, but with bit density and a tool pattern that has been taken from our productive reclaimer universal rotor,” Eiden said. It can be configured with bolt-on paddle toolholder protection for full-depth reclamation or wedge protection to reduce drag for soil stabilization.

Traction and maneuverability

The front-to-rear weight distribution of the new reclaimers has been optimized for stability in tough cuts, said Caterpillar, with standard electronically controlled all-wheel drive maximizing traction and mobility.

“The traction control system on these machines uses the same philosophy as the other Cat reclaimers, using four propel pumps – one for every wheel motor rather than a single propel pump or double propel pump and a flow divider,” Eiden explained. “This system is just more efficient. By measuring hydraulic pressure on each wheel, the system can detect any slippage and deliver pressure more evenly to all wheels on the machine.”

Four height-adjustable legs provide up to +/- 12.5% (8 degrees) of slope on either side for operation in uneven terrain or to maintain traction in challenging soil stabilization applications, improving stability and cutting precision, the company said.

Wheels are positioned at the corners, enabling a 10.1-ft. (3.1-m) inside turning radius. Front-only, rear-only, crab and coordinated steering modes further improve on-site maneuverability.

Enhanced visibility and control

A Caterpillar exclusive on the new machines is a hydraulically sliding cab that can be easily positioned from side to side to enhance visibility to the front and sides of the machine. “The operator station rotates 90 degrees in either direction for a full 180 degrees of movement,” Eiden added. “Whether working from the right side or from the left side of the machine, the operator can find a comfortable position for maximum visibility.”

The new planetary gear drive in the rotor enables the RM600 and RM800 to handle the heavier cuts demanded of these machines. (Photo: Caterpillar)

Floor-to-ceiling glass and an angle pane on the right-hand side further enhance visibility to the work area and the leading edge of the cutting chamber. Standard front- and rear-mounted cameras mounted above the front and rear mixing chamber doors provide configurable guidelines on the cab’s 10-in. color touchscreen display, as well as visibility to obstructions and material gradation. Optional side-mount cameras provide views to each side of the machine.

Controls mounted on the armrests of the operator station are grouped by function for fingertip access. A small handwheel provides precise steering, with the operator able to match machine speed and functions to gradation specification using the touchscreen display and pushbutton controls, Caterpillar said.

Automatic load control maintains rotor mixing depth and optimizes machine speed to ensure mix quality. Adjusting the front and rear mixing chamber doors enables instant modification of material gradation, and an easy-to-read indicator on the touchscreen display informs the operator of door positions, said Caterpillar. A rear rotor chamber door float feature allows the operator to select the desired down pressure. 

Exit and return-to-cut features simplify operation and ensure the machine maintains a consistent depth of cut, the company said. The RM600 and RM800 also offer bi-directional cutting capability.

Water or emulsion spray systems are available. Computerized metering enables accurate application rates, with variable flow rates of 8 to 500 gpm for water and 8 to 225 gpm for emulsion. The operator controls additive flow and customizes spray width from inside the cab.

Service friendly

The RM600 and RM800 are designed with service in mind. Ground-level controls allow the machine to be raised to service height for rotor access without requiring the operator to be in the cab. Service mode locks out any functions of the machine when service doors are open, enabling the engine to continue running for use of the standard onboard compressed air system.

Side service doors provide access to inspect or change end ring bits without reaching inside the rotor chamber. To further simplify rotor maintenance, the rotor can be hydraulically powered to turn in either direction using a control pendant.

The new models feature built-in diagnostics to monitor machine systems, alert the operator of performance issues and simplify troubleshooting. Product Link comes standard and enables the use of Cat Remote Services, such as Remote Troubleshoot and Remote Flash software updates.