Scrapers are used to move large amounts of materials, very fast. As we all know time is money! The faster (and safer) that we can move the materials into the locations that we need them, the better off we are. You will see many varieties of scrapers from several manufacturers on the large dirt jobs. They will have 1 engine (sometimes called single barrel) and others may have 2 engines! (sometimes called double barrel).
In construction, a wheeled tractor-scraper is a piece of heavy equipment used for earth-moving. The rear part of the scraper has a vertically movable hopper with a sharp horizontal front “cutting edge” which can be raised or lowered. The cutting edge slices into the soil, like a carpenter’s plane cutting wood, and fills the hopper. When the hopper is full it is raised, closed, and the scraper can transport its load to the fill area where it is dumped. With a type called an “elevating scraper” or a “self-loading” scraper, a paddle wheel helps move material from the cutting edge into the hopper.