A hydraulic excavator is a machine that is used to dig holes and trenches. Equipped with a hydraulically operated arm and bucket, the hydraulic excavator is often used to dig basements, ponds, ditches and is even used in strip mining. While this excavator can be mounted on a truck chassis, the most common type is equipped with tracks. The tracked hydraulic excavator is able to work on soft and uneven ground where a wheeled vehicle might become stuck.
Though most often equipped with a large bucket, the hydraulic excavator can also be fitted with a large air hammer used to break up concrete. Other options include tree trimming attachments and powerful hammers that can drive pilings into the ground. Some of these machines are even equipped with large drills that can create holes in concrete and road ways. The hydraulic excavator is one of the most versatile pieces of heavy equipment found on any job site.
The hydraulic excavator uses a diesel engine in most applications to power a hydraulic pump. This pump feeds large hydraulic cylinders used to operate the boom as well as the dipper arm and bucket. The boom is the largest part of the excavator and rises up out of the body of the machine. The dipper arm is the smaller arm that is connected on one end to the boom and at the other end to the bucket or attachment.
Many people misidentify a hydraulic excavator with a crane. Both units use tracked undercarriages to move around the job site, but this is where the similarity ends. The hydraulic excavator uses a boom for reach and completes its work with a bucket or some other attachment. A crane has a large boom which is open and hollow with a cable running through it. The crane uses this cable to move materials and the boom serves to give the crane its height..
While these excavators are found on job sites all around the world, they are unable to travel any great distance unaided. The machines must be delivered to the job site by tractor trailer or in some remote locations, by helicopter. The track drive system is only used to move the machine around while on the job site. The excavator moves at a very slow pace and the tracks serve as a working platform more than a drive system. The huge steel tracks are a fine supporter of the machine's weight and make the excavator extremely stable while working.