Grader

A early towed grader in unrestored condition

A grader, also commonly referred to as a road grader, a blade, a maintainer or a motor grader, is an engineering vehicle with a large blade used to create a flat surface. Typical models have three axles, with the engine and cab situated above the rear axles at one end of the vehicle and a third axle at the front end of the vehicle, with the blade in between.

History

The first graders were basically a wide board attached to a set of shafts and pulled by a team or pair of horses to level land out.

The early Iron framed graders were still pulled by horses, before tractors started to be used in the late 1890s, followed by the crawler tractor in the 1920s, and re invention of the self propelled machine by removing the front axle of a tractor and boltring a long frame with the axle on abd a blade under neath, adjusted by a hand wheel.

Usage

Aveling Barford grader in S.E. Davis and Sons yard

In civil engineering, the grader's purpose is to "finish grade" (refine, set precisely) the "rough grading" performed by heavier construction plant such as motor scrapers and bulldozers.

Graders can produce inclined surfaces and surfaces with cambered cross-sections for roads. In some countries they are used to produce drainage ditches with shallow 'v'-shaped cross-sections on either side of highways.

Graders are commonly used in the construction and maintenance of dirt roads and gravel roads. In the construction of paved roads they are used to prepare the base course to create a wide flat surface for the asphalt to be placed on. Graders are also used to set the ground to finish grade prior to the construction of large buildings.

UK Usage

In the UK most graders are employed in opencast sites and quarries for roadway maintenance. A few are coming back into usage for roadway construction, with some contractor. Several were seen recently on the M1 motorway widening works, in Derbyshire. This in part may be due to the use of rubber tyres instrad of tracks and the ability to not need a low loader to re locate over the sections with tarmac surfaces laid, and to profile the batters down to the drainage channels quickly.

Allen of Oxford graders were widely used for airfield construction during the second world war for obtaining a finishing level, prior to grass seeding.

USA/Canadian

In some locales such as Canada and places in the United States, graders are often used in municipal/residential snow removal. In scrub-land and grassland areas of Australia and Africa, graders are often an essential piece of equipment on ranches, large farms and plantations to make dirt tracks where the absence of rocks and trees means bulldozers are not required. A more recent innovation is the outfitting of graders with GPS technology, such as manufactured by Topcon Positioning Systems, Inc., Trimble Inc., for precise grade control and (potentially) "stakeless" construction.

Capacities range from a blade width of 2.50 to 7.30 m and engines from 93–373 kW (125–500 hp).

Education

• In the USA, The National Association of Heavy Equipment Training Schools (NAHETS), established 2002, uses grader training schools and curriculum as a method to test and train users in the ability of grader use.
• UK Training certification by CITB (Construction Industry Training Board), Based at Birch Newton in Norfolk, An old RAF base from the 2nd WW. To operate plant on construction site generally a CPCS card is required in the UK to prove competence, and a understanding of H&S

Some other grader-producing companies

A J&F Howard towed grader sn 294

• ACCO (Italy) - Worlds biggest grader
• Adams (taken iver by Wabco in 1955)
• Akerman (Sweden)
• Allis-Chalmers
• Astarsa (Argentina) - licensed Caterpillar
• Austin-Western
• Aveling-Austin UK built licensed Austin-Western models
• Aveling-Barford
• Blaw-Knox (UK)
• BLH - took over Austin-Western
• Caterpillar
• Case CE
• Champion (Taken over by Volvo)
• CIMT (France ?)
• Clark Equipment Company tookover BLH
• Conarg (Argentina)
• Fiat-Allis succesort to Allis-Chalmers grader line
• Frisch (Germany)
• Galion
• Galion-Wakefield (UK)
• Grosspal (Argentina)
• Grove ? in USA ?
• Hanomag (Germany)
• Henschel (Germany)
• Hidro-Grubert (Argentina)
• Hitachi Construction Machinery (Europe)
• Hough
• J&F Howard
• Huber-Warco
• Ingersoll-Rand
• John Deere
• KLIA (Argentina)
• Kockum Landsverk Industria Argentina
• Komatsu
• LeTourneau Inc. (USA) - electric drive mining graders
• Lokomo (Finland)
• Merex (Argentina)
• Moncalvi (Italy)
• New Holland
• O&K (Germany)
• Pauny (Argentina)
• Richier (France)
• Rotania (Argentina)
• SIAM (Argentina) - Wabco licensed
• Terex
• Ursus-Peroni (Italy)
• Vacini became Sicom (Italy)
• Volvo Construction Equipment
• Wagner (USA)
• Wakefield (UK)
• Western
• Zanello (Argentina)

See also

• UK Operators CITB / CPCS Training / competency cards - http://www.citb.org.uk/cardschemes/whatcardschemesareavailable/cpcs/

• National Association of Heavy Equipment Training Schools—U.S. educational organization

References/sources

• The History of Road Building Equipment (book), published by KHL group