Excavator
An excavator is an engineering vehicle consisting of a backhoe and cab mounted on a pivot atop an undercarrage with tracks or wheels.
Note: the term excavator is sometimes used as a general term for any piece of digging equipment. Tracked excavators are sometimes called trackhoes.
Excavators are mostly used to dig trenches and holes. They come in a wide variety of sizes. The smaller ones are called "mini-excavators" or "compact excavators". One manufacturer's largest model weighs 79200 kg (174,606 lbs.) and has a maximum bucket size of 4520 litre (5.91 cu yd.). The same manufacturer's smallest mini-excavator weighs 1470 kg (3240 lbs), has a maximum bucket size of 36 L (0.048 cu yd) and the width of its tracks can be adjusted to 89 cm (35 inches). Another company makes a mini excavator that will fit through a doorway with tracks that can be adjusted to only 70 cm (28 inch) wide.
Often the bucket can be replaced with other tools like a breaker, a grapple or an auger. Excavators are usually employed together with loaders and bulldozers.
Most smaller excavators have a small backfill blade. It's a horizontal bulldozer like blade attached to the undercarriage and is used for pushing removed material back into a hole.
Most excavators travel on tracks but others have wheels.
