Е. С. Закирова, П. А. Красавин Английский язык для технических вузов
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| EARTHMOVING MACHINERY
A scraper is a heavy earthmoving machine. The rear part has a vertically moveable hopper (also known as the bowl) with a sharp horizontal front edge. The hopper can be lowered and raised. Scrapers can be very efficient on short distances where the cut and fill areas are close together and have sufficient length to fill the hopper. Most often, scrapers are large and powerful wheeled machines. But some scrapers are tracked heavy machines. The tracks give them excellent ground hold and mobility through a very rough surface. A bulldozer is a machine equipped with a substantial metal plate (known as a blade) used to push large quantities of soil, sand, or other material. Bull- dozers are also used to loosen densely-compacted materials with a claw-like device (known as a ripper) placed at the rear. There are two types of bulldozer: crawler bulldozer (crawler dozer) and wheeled bulldozer (wheel dozer). 190 A grader is a construction machine with a long blade used to create a flat surface, to finish the “rough grading” performed by scrapers and bulldozers. Graders are commonly used in the construction and maintenance of roads or in the preparation of the base for a wide flat surface for the asphalt to be placed on or to finish grade prior to the construction of large buildings. A more recent innovation is the outfitting of graders with GPS technology. Excavators tracked or wheeled are heavy construction machines the parts of which are boom, sticks, bucket and cab on a rotating platform (known as the “house”). Excavators are also called diggers, mechanical shovels, or 360-de- gree excavators (sometimes abbreviated simply to 360). Terex TS-14b scraper in Hudson, Ohio A bulldozer, Hainan, China A modern road grader |