Cat’s RM-500 Boasts Enhanced Productivity Features

Thu August 10, 2006 - National Edition
Construction Equipment Guide

Caterpillar Inc. has announced the availability of the RM-500 rotary mixer. The RM-500 replaced the RM-350B reclaimer mixer.

The RM-500 features a Cat C15 engine with ACERT Technology that is U.S. EPA Tier 3 and EU Stage IIIa emission compliant. It offers features and options that increase operator comfort and productivity such as a sliding operator’s station, pressurized cab, automatic rotor depth control, four mode steering, all wheel drive and three rotor design options.

The RM-500 is powered by a Cat C15 engine with ACERT Technology. The C15 engine is a turbocharged, six-cylinder diesel engine that provides 540 hp (403 kW) of gross power (SAE J1995), an 8 percent increase over the RM-350B. ACERT Technology utilizes an electronic controller to precisely deliver multiple injections of fuel.

These multiple injections are combined with a refined air management system in order to generate fewer emissions and optimize fuel combustion while meeting U.S. EPA Tier 3 and EU Stage IIIa emission regulations for off-road applications.

The turbocharged air-to-air aftercooling system provides high horsepower with increased response time while keeping air inlet temperatures low. This generates improvements in airflow that increase efficiency and reduce emissions, according to the manufacturer.

The modular stacked cooling system provides cool intake air that helps maximize fuel efficiency and minimize emissions. An on-demand variable speed fan draws ambient air from the top of the engine hood and through the cooling package. The exhaust air exits from the front of the machine, providing a cool engine compartment and operator’s platform.

Operating weight for the RM-500 is approximately 62,060 lbs. (28,145 kg) when equipped with a ROPS, a cab and a universal rotor.

The new RM-500 offers several improvements over the RM-350B, including increased tractive effort, improved weight balance, easier serviceability, greater versatility and higher production, the manufacturer said.

The RM-500 comes standard with full time all-wheel drive. Two independent variable displacement propel pumps supply balanced oil flow to the front drive motors and the rear drive motors. Two speed ranges allow operation at either maximum torque for work or greater speed for moving around the job site.

Gear selection is controlled electrically by a two-position switch on the operator’s console. Infinite variable speed control within these ranges is achieved utilizing the propel lever and speed control dial.

The large tires have an aggressive tread and provide a large footprint. Machine weight balance provides stability to the machine when cutting and mixing, resulting in a consistent depth.

The mixing chamber is a large volume, heavy-duty hood that allows the rotor to move independently, a feature that increases or decreases chamber volume depending on the depth of the rotor. This provides better material mixing even at extreme material depth. Hydraulically-adjustable doors on the front and rear of the chamber provide increased control of gradation and material uniformity while operating in either forward or reverse direction.

Three rotor styles are available on the RM-500. The universal rotor, designed to improve machine versatility by providing full depth reclamation and soil stabilization performance without changing rotors, is 96 in. (244 cm) wide and has a maximum cutting depth of 16 in. (41 cm).

The soil rotor, designed for soil stabilization applications, has a width of 96 in. (244 cm) and a 20 in. (51 cm) mixing depth.

The combination rotor, for soil stabilization and light asphalt reclamation, has a width of 96 in. (244 cm) and a 20 in. (51 cm) mixing depth.

The hydraulically-assisted operator’s station is standard on the RM-500 and slides from side-to-side to an infinite number of positions. A switch on the side control console allows the operator to select any desired position for increased versatility and overall visibility.

Placing the operator’s station to the far left or right side of the machine enhances visibility to the front of the machine and provides improved sight lines to the front tire edge.

Moving the operator’s station from one side of the machine to the other side takes approximately 20 seconds. The operator can move the operator’s station quickly during machine operation for faster cycle times and increased production.

Wide, comfortable steps with non-skid surfaces are placed to provide access to the operator’s station from either side of the machine. The steps and handrails are recessed within the overall machine width to minimize exposure to potential damage. The top deck is flat, providing access to either side of the operator’s seat.

The seat has adjustable fore/aft positioning, bottom cushion height, suspension stiffness and flip-up arm rests. The seat and side control console rotates to seven positions to further enhance operator comfort. The seat also includes a 3-in. (7.6 cm) wide seat belt.

The steering column is infinitely adjustable within the tilt range and has a telescoping feature for additional operator comfort and easier access to the seat.

The side console moves and rotates with the seat and features a padded arm rest, the four mode steering switch, speed control dial, propel lever, rotor elevation switches, rear rotor hood door switch, sliding operator’s station switch, rear steering switch and front rotor hood door switch. The speed control dial allows the operator to set the maximum propel speed attainable at the fully forward or rearward position of the propel lever. This standard feature is especially useful when the machine is started and stopped frequently, according to the manufacturer.

The front control console has been designed to emphasize operator comfort, visibility and ease of operation. The console features large, easy-to-read gauges, function indicators and warning indicators to keep the operator informed of machine operation and vital systems.

The large LED display panel shows information selected by the operator such as rotor depth, propel speed selection, steering modes, rotor speed and various other control switch positions. All gauges and displays are easily visible in direct sunlight or low light conditions. Functional switches are positioned within easy reach of the operator.

The optional cab on the RM-500 is fully pressurized to provide a comfortable environment for the operator while keeping noise, dust and the elements out.

Features included with the cab are: a rotating cloth seat, sound absorbing headliner, left and right side lockable doors, tinted glass, air conditioning, heater/defroster and dual front and rear windshield washer/wipers.

Noise levels in the cab and at ground level have been reduced, providing greater operator comfort and less noise emitted to the surrounding environment. A sound absorbing floor mat is standard and provides sure footing while reducing noise and vibration transmitted to the operator.

Four large isolation mounts isolate the cab from the machine frame to reduce vibration transfer to the operator’s station.

On-board microprocessors monitor operating conditions, receiving input signals from sensors in the engine, propel, steering and rotor drive systems. Self-diagnostic programs provide information for troubleshooting and alert the operator of potential system problems. If a machine fault occurs, a code is displayed on the LED display panel to alert the operator and assist in troubleshooting.

In addition, there are three warning levels depending upon the severity of the fault:

• A level one warning consists of a flashing gauge indicator and alert indicator light. Typically, the operator can continue to operate; however, the system requires attention soon.

• A level two warning includes a level one warning plus the warning action lamp flashes. This indicates that the operator should change machine operation or perform the required maintenance to the system as soon as possible.

• A level three warning includes a level two warning plus the warning action horn sounds continuously. When this occurs, the machine should be shut down immediately in a safe manner.

Automatic rotor load control is another standard feature to enhance machine productivity. The on-board microprocessor constantly evaluates engine rpm and propel speed as required to maintain peak performance. The microprocessor matches propel speed of the machine to the load on the engine and adjusts propel speed so that engine speed does not drop below 1,800 rpm.

The operator can activate the automatic load control with an On/Off switch located on the front control console.

The RM-500 provides three modes of rotor depth control. During operation, the microprocessor receives input from the rotor position sensor, three-position rotor mode switch and rotor raise/lower switch. Control of rotor depth is through the raise/lower switch and the three-position rotor mode switch.

The three modes of rotor depth control are:

• Travel Mode: When the selector switch is moved up to the Travel position, the rotor moves to a factory-calibrated full-up position and remains there. This provides clearance for moving the machine over obstructions or traveling between job sites.

• Manual Mode: In this mode, the operator controls the position of the rotor by using the Raise/Lower switch. A visual depth gauge is positioned on each rotor lift cylinder so the operator can precisely control the cutting depth of the rotor from the operator’s station.

• Automatic Mode: Selecting the Automatic position provides automatic rotor depth control. In this mode, the microprocessor maintains rotor depth at the position set by the operator. Rotor depth is displayed on the LED display panel. The numbers will show in either inches or millimeters.

A plus sign (+) means the rotor is above ground, a minus sign (-) means the rotor is below ground. A scale on the LCD display panel indicates the position of the rotor.

The RM-500 is equipped with four mode steering. The microprocessor processes inputs from sensors on the front and rear wheels along with input from the four mode steering selector switch. It provides simultaneous wheel movement in the crab and coordinated steering modes and automatically realigns the rear wheels to center when the front wheels only steering mode is selected. In the coordinated mode, the inside turning radius is a tight 12 ft. 1 in. (3.7 m).

The rotor drive system operates directly through a Caterpillar powershift transmission and drive axle. The mechanical rotor drive system allows transfer of engine power to the rotor and is sized to handle tough cutting and deep mixing. The On/Off switch on the operator’s console controls the engagement of the rotor transmission.

A choice of three rotor speeds permits working in a wide range of materials, depths and applications. First speed is used primarily for pulverizing the material. Second or third rotor speeds can be used in blending or mixing passes. A three-position, rotor speed selection switch on the operator’s console determines rotor speed.

The rotor is driven on both sides by single strand, high strength drive chains which are contained in heavy-duty chain cases partially filled with oil. A shear disc or optional torque limiter protects the rotor drive components from shock loads.

Three rotors are available for the RM-500:

The universal rotor can be used for either full depth reclamation or soil stabilization and is equipped with 200 point-attack carbide-tipped tools mounted in drive-in, knock-out, bolt-on tool holders and arranged in a chevron pattern for maximum breakout force.

The point-attack type tools have long been the standard selection for reclamation applications. The rotor ends are equipped with triple-tree tool placement that provides optimum tool spacing to clean up loose material and reduces drum wear when maneuvering in the cut. Maximum cutting and mixing depth is 16 in. (41 cm ).

The soil rotor is used for a variety of soil applications and blends additives with cohesive, semi-cohesive or granular materials.

The rotor is equipped with 238 point-attack, carbide tipped tools mounted in drive-in, knock-out, weld-on tool holders and arranged in a chevron pattern for maximum breakout force. Replaceable end rings protect rotor mandrel from wear. The rings are hard-faced for extended service. The rotor has a maximum mixing depth of 20 in. (51 cm).

The combination rotor is designed primarily for use in soil stabilization applications, but also works well for light asphalt reclamation.

The rotor is equipped with 114 point-attack, carbide-tipped tools mounted in drive-in, knock-out, bolt-on tool holders and arranged in a chevron pattern for maximum breakout force. Its design is intended for applications where material gradation is of less importance and where higher working speeds are desired. Replaceable end rings protect rotor mandrel from wear. The rings are hard-faced for extended service. The rotor has a maximum mixing depth of 20 in. (51 cm).

The large, variable-volume mixing chamber is mounted mid-point between the front and rear tires for optimal weight distribution. When the operator uses the automatic depth control system, the microprocessor ensures accurate depth of cut by sensing and responding to surface variations.

The machine is able to work in both forward and reverse due to adjustable front and rear doors on the mixing chamber. The heavy-duty front door is powered with two hydraulic cylinders for raise and lower. The front door raises parallel to the cutting surface to prevent the door from plowing material in harsh soil stabilization conditions. This is practical for peak efficiency on soil stabilization, bio-remediation or during mixing passes on full depth reclamation.

Other options include: a roll over protective structure (ROPS), a falling object protective structure (FOPS), a road operation light package, a warning beacon light, a mirror package, an umbrella, a counterweight kit and a water spray system.

Daily service points are accessible from ground level and are grouped. The one-piece fiberglass hood tilts forward for increased access to the engine and cooling system. Hinged ground level side panels open wide for even greater access to engine components.

The hydraulic rotor hood rotates forward to allow access to the rotor and cutting tools and is held securely in place with a heavy chain. Ground level side access doors on the rotor hood provide convenient access for easy cutting tool removal and replacement.

The rotor drive-chains self-lubricate in sealed chain cases partially filled with oil. A lubrication reservoir for the stub shaft bearing is mounted on the front of the hydraulic tank. The reservoir has two separate chambers providing oil to each stub shaft. Oil level is easily monitored from the operator’s station, providing quick visual verification of sufficient oil levels for each stub shaft.

Other features that make servicing simple include leak-resistant O-ring face seal hydraulic fittings, grouped quick-connect hydraulic test ports, S•O•S ports, visual site gauges and remote grease points.

Hydraulic hoses are held neatly in place with polyurethane routing blocks. The blocks prevent hoses from rubbing against one another, extending the service life and reliability of the hose.

Wiring for the electrical system is protected by nylon-braided wrap. All-weather connectors ensure electrical system integrity. Electrical wiring is color-coded, numbered and labeled with component identifiers to simplify troubleshooting.

Two maintenance-free Caterpillar batteries power the 24-volt electrical system and are specifically designed for maximum cranking power and protection against vibration. The batteries are mounted on the side of the machine and are accessible from ground level.

The machine is Product Link wire-ready. The Caterpillar Product Link System (CPLS) ensures maximum uptime and minimum repair costs by simplifying tracking of equipment fleets. The CPLS provides automatic machine location and hour updates. CPLS can be obtained through a local Caterpillar dealer.

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