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Canada's “Rock to Road”
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Focus on motor graders Volvo/Champion
Champion Compact graders offer a tight turning radius of 5029 mm. Volvo Construction Equipment Group has introduced its new Champion Series VI 700 and Compact motor graders. The Series VI product line includes twenty-three models from 80 hp to 235 hp and machine weights ranging from 4273 kg to 19 388 kg. High-torque engines, available in either variable horsepower or standard power in the Series VI 700 graders, deliver up to 53 per cent net torque rise for maximum high-load performance. The 700 models are equipped with the Champion 8400 transmission which provides 8 forward and four reverse evenly-stepped speeds up to 44.8 km/h. By optimizing weight placement over the drive wheels and over a long blade base, and by putting more engine power to the ground, the new Series VI graders offer industry leading pull-down pressure, according to the manufacturer. Champion Series VI 700 AWD models (716A VHP, 726A VHP and 736A VHP) have a revolutionary all-wheel-drive system that delivers maximum power with maximum precision, states Volvo. The Champion AWD system provides even distribution of power through independent variable displacement pumps and high torque motors at each front wheel. If traction differs on either side, the system ensures that optimum pulling power is still achieved. Speed sensors on each front wheel control the relative front-to-rear wheel speed. Exclusive creep mode on AWD models provide infinite speed selection from 0-3.2 km/h. Also exclusive on Champion AWD graders is a new system that gives the operator the ability to switch to the patented creep mode for low-speed, fine grading applications. Creep mode, which provides infinite speed selection, disengages the rear drive and front-wheel drive only. This puts power where it is most effective for fine grading and allows the moldboard to be navigated around the tightest corners without the rear wheel "scuffing" the final grade. Champion’s moveable blade control system (MBCS) allows the operator to accurately position the blade on either side of the grader at any angle up to 90 degrees for bank-sloping and to 21 degrees downward for ditching, making it simple and easy to cut an exact profile. Available in either full height or low profile configurations, the cab on each Series VI machine is said to offer excellent climate control, convenient operating controls and 360 degree visibility. The front frame and rear cowling are sloped downward to open up the operator’s line of sight. The 360 degree visibility gives clear views around the grader to see the road and attachments, the blade and the area around the front wheels to see grade stakes. The new hydrostatic-drive Champion Compact grader models, with machine weights ranging from 4273 kg for the 80 hp C50A to 7205 kg for the 110 hp C86A, have been designed to carry out a wide range of tasks in areas where larger graders can’t go. One of the most important features of the Compact graders, according to the manufac-turer, is their ability to maneuver in tight situations and work into corners because of a minimum turning radius of 5029 mm. The compact models are equipped with a simple, robust, trunnion-mounted blade control system with dual-cylinder, direct-acting circle turn system. Hydraulic controls include detent-style float valves and twin-flow hydraulics for improved blade mobility, precision and reach. The new models also feature an adjustable pedestal and twin flow hydraulics plus dual-lever speed and directional controls for easy operation of the hydrostatic transmission. The control pedestal and console are similar to the design of the larger grader cabs. John Deere
New John Deere 770C grader features a 155 hp Deere Powertech 8.1 litre diesel and a Deere directdrive countershaft transmission. Available from John Deere is the C-Series motor grader line that offers six models ranging in net horsepower from 140 to 205. Improvements over previous models include a new transmission, emissions-certified and fuel-efficient engines, easy-to-use gear selector and extra horsepower in the all-wheel-drive machines. The C-series lineup includes four variable horsepower graders - the 670CH (140/155 hp), the 672CH (150/160 hp), the 770CH (155/170/185 hp) and the 772CH (170/185/ 200 hp or 185/205 hp when all-wheel drive is engaged). The other models offered are the 670C (140 hp) and the 770C (155 hp). According to the manufacturer, the most significant improvement to the C-series motor graders is the new Deere electronically controlled powershift transmission. Built specifically for the C-Series graders, the Powershift Plus™ direct-drive countershaft transmission delivers smooth shifts between eight forward and eight reverse gears. Travel speeds for 700 models are identical in forward and reverse, from 3.5 km/h to 41.5 km/h. Also, drawbar pull is nearly the same in both directions, providing enough power for backing up inclines and getting out of trouble spots. The C-Series motor graders are equipped with John Deere-built, 6-cylinder Powertech™ turbocharged diesel engines that are designed for lighter, better horse power-to-weight ratio and improved fuel efficiency. The deep-skirt design makes the engine quieter, with less vibration, states the manufacturer. The 600 C-Series models are powered by 6.8 litre displacement Powertech engine while the 700 C-Series machines use the 8.1 litre Powertech engine. All C-Series graders, except the 670C, are equipped with a waste-gate turbocharger that delivers high-torque and superior lugging ability and provides improved performance at lower engine rpm settings and at higher altitudes. The closed-centre hydraulic system has its own separate oil lubrication, filtration and cooling system to prevent cross con-tamination. The main hydraulic valve is isolation-mounted on top of the mainframe in front of the cab, protecting it from damage and making it easier to service. The graders feature a planetary axle with fully modu-lated, inboard, wet multi-disk brakes. Right-and left-side brakes function independently. If a failure should occur on one side, the opposite side is still functional. An eight-way adjustable fabric-covered seat with armrest tilt and lumbar support tops the list of improved operator comforts. Engine sideshields taper inward, providing a better view of the ripper. The sloped hood improves rear visibility for work in crowded jobsites. A new shifter with U-shaped pattern makes gear changes easier. Komatsu Komatsu's new 19 000 kg GD750A-1 grader has four-wheel-drive and a 225 hp turbocharged diesel engine. Earlier this year, Komatsu America in troduced the new 19 000 kg GD750A-1 motor grader to North America. The four-wheel- drive machine features an articulated frame and moldboard geometry that enables the operator to position the blade 90 degrees to the right or left. It has a maximum cutting depth of 685 mm, a maximum lift above ground of 420 mm and a blade tip range of 46 degrees forward and 7.5 degrees backward. The new model is powered by a 225 hp, turbocharged Cummins M11-C diesel engine. Design features include Komatsu’s torque converter with lockup direct-drive technology, load-sensing hydraulics, elec-tronic monitoring system and human-first engineered design. The GD750A-1 has a full powershift transmission with integral free-wheeling stator type torque converter and lockup. With a top speed of 48 km/h, the grader features eight forward and four reverse speeds. One of the machine’s key features, according to Komatsu, is the torque converter with lockup direct drive. By multiplying engine torque and delivering it to the power train when required, torque converters can decrease the need for shifting and increase tractive effort. An operator can simply select a gear range and work right down to zero km/h with full hydraulic response. The torque converter feature also allows the operator to run the machine smoothly by using only a brake pedal. Komatsu says this function will assist tasks such as fine grading because the operator will be able to better concentrate on moving the blade. In addition, the torque converter with lockup direct drive gives the operator the benefit of a torque converter to start with heavy loads without stalling the engine and the benefit of a direct drive with the converter lockup at higher speeds. When the GD750A-1 is in the upper gear ranges, it automatically goes into direct drive. An added benefit, says the manufacturer, is better fuel efficiency. The ergonomically-designed cab offers improved visibility of the blade, front tire, tandem tires and rear ripper from both the front and side windshields which extend all the way down the side of the door. Control levers are configured to industry standards and all the gauges are positioned in front of the operator. The load-sensing hydraulics with variable displacement system eases operation and provides ‘feather-touch’ response. The braking system has three safety levels that ensure braking even if the engine is dead. There are the standard foot-operated, sealed oil disc brakes which are hydraulically- actuated on four tandem tires. Secondly, if the operator encounters a dead engine there is a nitrogen accumulator safety system that backs up the power. Finally, if for any reason the first two braking systems fail, the operator still has the parking brake which is activated automatically. The GD750A-1 is equipped with an elec-tronic self-diagnostic system that minimizes unplanned downtime by monitoring and tracking the operating condition of the machine and providing diagnostic data to ensure optimum performance. By Andy Bateman, Engineering Editor Aggregates
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