Road graders are also commonly known as graders and they are large wheeled vehicles that are mainly used in road construction to either smooth roads or uniformly spread tar, concrete and gravel. A road grader has six wheels with tandem drive and a set of blades between the front and middle wheels. A single drive axle with roller chains drives the rear wheels. The blades are hydraulically powered and can be raised to a precise height, which allows the required amount of material to be deposited. The blade can also be set at a specific angle. The blade performs actions such as left lift/drop, right lift/drop, circle left/right and blade rotate. The width of an average blade is about 12 feet which is about the standard width of a highway driving lane. A ripper may also be provided at the rear to dig up small stones and loose gravel.
The width of the blade width, the engine horsepower, the vehicle weight and the grader’s maximum speed classify road graders. Road graders commonly are used to build roads on highways, forests, airports and rocky terrains. After the land has been excavated by a bulldozer, the road grader is then used to smooth, even and flatten it out. These graders are also used to level out the land on building sites before construction begins.
The typical roadway grader weighs about 15 tons and the vehicle is approximately 28 feet long and 8 feet wide. In terms of power, roadway graders usually range from about 150-180 in horsepower. Some older model road graders may be lighter in weight and be less powerful, but overall, road graders haven’t changed much over the past 50 years.
The operator of the grader sits atop of the vehicle in an enclosed cabin. Considerable skill is needed in operating a grader and experienced operators employ skills like leaning to counter the pull of the blade. Most operators grade by feel because the grading zone is below the grader body. Because road graders are extremely heavy and can be very dangerous so it’s imperative that only skilled, qualified and certified people operate them.