Two new rubber-tired rollers have lots of horsepower, refined hydrostatic drive, innovative steering and adjustable operating weights
With operating weights that can be adjusted from approximately 10 to 30 tons, the new BW24RH and BW27RH pneumatic (rubber-tired) rollers are suited to a wide range of compaction chores, says Bomag, including base preparation, soil and asphalt finishing, soil stabilization and chip/seal resurfacing. Bomag has designed these machines to meet two specific operating-weight classes, 25 and 30 tons, but the new models have the flexibility, depending on ballast loading, to operate from around 9.5 to 26.5 tons (BW24RH) and from 14.5 to 30 tons (BW27RH).
To achieve the correct operating weight for the application, the rollers can be ballasted with water, sand, steel shot or scrap steel. Both have a 124-cubic-foot ballast compartment, which has a large opening on either side of the machine to facilitate ballast removal. The units also can be "pre-ballasted" by attaching individual weights under the frame. With maximum ballast, the BW24RH tops out at 52,911 pounds, and the BW27RH at 59,525 pounds. These weights provide a maximum middle-wheel load of 6,614 and 7,441 pounds, respectively.
The new rollers are fitted with eight, 11.00-20 18PR tires that provide total-width coverage of 83.4 inches, allowing for a 2-inch tire-track overlap. An automatic inflation system controls tire pressure, which the operator can easily regulate from the cab, even when the machine is working. According to Bomag, the tires provide a kneading action that results in highly uniform compaction and a dense finish at the surface.
Both new machines feature a hydrostatic drive system that uses two hydraulic motors to power the four rear wheels. The machines' hydrostatic pump powers the motors, which, in turn, work through gearing to power the wheels. Two working ranges allow top speeds of 4 and 12 mph, respectively. The rollers are powered by Deutz BF-4M 2012 diesel engines, rated at 99 and 131 horsepower, respectively.
New for these machines is a two-point-oscillation steering system, which allows the inside and outside front-tire pairs to turn at different rates. Much like a spilt drum on a tandem roller, says Bomag, the steering system provides smooth transitions and reduces the potential for damaging the mat surface. And to minimize the potential for material pickup on the tires, a corrosion-resistant, 106-gallon water tank supplies a pressurized spray system.
|Width across tires (in.)||80.4|
|Total rolling width (in.)||83.4|
|Overall height (in.)||121.7|
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