A long reach excavator is an excavator with an extremely long boom and stick attached, or what is commonly called the arm. Used to dig very deep holes and trenches, many long reach excavator jobs entail digging a river or lake bottom while the excavator is sitting on a barge or floating platform. Commonly equipped with an over-sized counterweight to offset the leverage of the long reach boom and stick, the long reach excavator is also used to reach heights with jackhammer attachments as well as other implements. When fitted with a mechanical thumb attachment, the long reach machine is used to lift poles, pipes and other materials to extreme heights.
An excavator is a track-equipped machine that has a bucket attached to a boom and stick to dig holes and trenches. Much like a backhoe on tracks, the excavator is a common sight on many construction sites. While perfectly equipped to dig large basement holes and trenches, the excavator is limited in the depth it can dig by the size of the boom and pick it is equipped with. The boom is the main part of the machine's arm, while the pick extends down from the boom and attaches to the bucket. Hydraulic cylinders power the movements of all three components: the boom, the pick and the bucket.
Creating a long reach excavator is more involved than simply bolting a longer boom and pick onto a typical excavator. Longer hydraulic cylinders must also be installed to allow for the additional reach and movement the longer components allow the long reach excavator to make. The long reach excavator must also be equipped with an over-sized counterbalance to offset not only the weight of the much heavier boom and pick assembly, but also to counterbalance the added leverage the long reach excavator adds when the bucket is full. Failure to add the additional counterbalance could result in the excavator being toppled over when attempting to raise the loaded bucket.
Transportation to and from the job site is made much more difficult with a long reach excavator. The added length of the boom and pick commonly require the entire assembly to be removed from the excavator and hauled in a separate truck. Often, the counterweight must also be shipped separately due to its extreme weight. These transportation issues, coupled with the rare instances that a long reach excavator is required on a job site, are often a deciding factor behind a company's logic for renting the machine only when needed rather than purchasing the excavator outright.