Earthmoving OverviewEarth-moving equipment is for digging, moving and discarding material, materials such as dirt and soil; rock, gravel and sand; snow; and demolition debris such as concrete, lumber and steel. There are three categories of earth-moving equipment: those that push, those that dig, and those that scoop. Loaders scoop; excavators dig; and dozers push. There are only two types within the three categories of earth-moving equipment: tire and track. Rubber tire earth-moving equipment includes tractors and landscape loaders, backhoes and loaders and wheel skidsteers. Earth-moving equipment on tracks include bulldozers, excavators, mini excavators, drilling rigs and track skidsteers.
How do you know which machine is right for the job?
There are a number of earth-moving machines that can perform several functions. A backhoe can both scoop with the loader implement on the front and dig with the hoe on the back. Both backhoes and front-end loaders are also adept at pushing material, as-well-as scooping, but not with the efficiency nor volume of a dozer. Dozers can dig and scoop at a rudimentary level, but not with any real efficiency.
Understanding the strengths and limitations of each category of earth-moving equipment is crucial. Choosing the right piece of equipment, or not, is the difference between saving time and money and not.
- Digging Equipment - Backhoes and excavators are the most adept at digging trenches and pits. In conjunction with the bucket, the arms and booms of each are designed to dig clean and precise trenches and holes. Excavators are synonymous with pipe: septic systems, water lines, and irrigation pipe, for example. They are also very useful in digging holes, quarry pits for example.
- Scooping Equipment - Loaders and the loader implements on the front of a backhoes are designed to scoop and lift or scoop and push material. Moving, disposing of, and loading material and spoils; loading trucks, trailers and end dumps with material and spoils; and putting the finishing touches on flat work -- when a grader or dozer is not available -- are all strengths of equipment with loader implements.
- Pushing Equipment - Dozers are earth pushers. Dozers are not only the most adept pusher, but the powerful earthmovers. Dozers also have the best traction of any category of equipment. Dozers are used to clear areas of debris, flatten areas, and slope and grade. The weight of a dozer almost makes compaction unnecessary. So powerful are dozers that a dozer the last, best resort when another piece of equipment gets stuck.
Common Types of Earthmoving Equipment
Backhoes are equipped with a scoop bucket on the front end and a boom and digging bucket on the rear. Backhoes can not scoop and move the same volume as front-end loaders, nor dig the same volume as an excavator, but are equally precise with regard to both functions. And, when a job requires both scooping and digging, a backhoe allows an operator to perform both jobs efficiently by eliminating the need to dismount one piece of equipment and crawl into another. Backhoes are the multitasking machines of earth-moving equipment.
Originally designed to function as a miniature loader, equip with a scoop bucket on the front, skidsteers have evolved into the ultimate mini-utility machines. The buckets on modern skidsteers are removable. Detachable implements including digging booms, jackhammers, jumping jacks, forks and blades can be mounted on a skidsteer. Skidsteers are available with rubber tires or rubber tracks. Skidsteers are extremely maneuverable in small spaces and can accelerate to top speed much faster than any other earthmover.
Crawler loaders have the power, purchase and stability of standard dozers, but rather than a blade, crawler loaders have an over-sized scoop bucket on the front and a ripper on the hind end.
An excavator is the most powerful and efficient of the digging earthmovers. In addition to digging greater volumes of material faster, as a track machine, an excavator is exponentially more stable than a backhoe or tractor or skidsteers mounted with a boom-and-bucket implement. The cab of an excavator sits on a turntable meaning an operator can rotate the cab 360 degrees without having to advance or reverse the tracks. The tracks, in combination with the boom, allow an excavator can perform maneuvering feats no other earth-moving equipment can. An excavator can cross a trench with a width just slightly less than the length of the excavator's tracks or summit short slopes with a grade of more than 45 degrees.
A loader can scoop, lift and move greater volumes of material than any other earthmover. Equip with an over-sized, front-end bucket and four equal, over-sized tires, no earthmover can move faster when loaded with material faster on a flat, clean surface.
What separates a tractor from other earthmovers is the power takeoff (P.T.O.), a splined shaft that spins at high rpm. Implements connected to the tractor can be powered by the p.t.o. There are hundreds of p.t.o. driven implements that can be hooked up to a tractor including rock rakes; rotatillers; mowers; seeders; sprayers; lift arms; snow blowers; and plows. Landscape loaders are tractors with arms and a scoop bucked mounted on the front.
A trencher looks like a machine with an over-sized chainsaw bar attached to it. The purpose of the chain and bar is to dig two to six-inch trenches. What makes a trencher more efficient than a mini excavator is the fact that a trencher can dig a very deep trench relative to the width of the cut. Trenchers are ideal for digging waterlines, electric lines, and gas lines -- utilities.
Other Considerations When Renting Earthmoving Equipment
Dimensions of the Equipment and Implements
The size of the equipment is a necessary factor to consider. Equally important is size of the bucket or blade. If a bucket or blade is too large or too small, issues can arise. For example, it is not necessary to have a 2-foot wide backhoe bucket when digging the trench for a 1-inch water pipe. In that case, a mini excavator would be more appropriate. But, a mini excavator will not suffice for 2-foot drainage pipe. It would take an excessive amount of time to dig the trench and the mini excavator could not lift the concrete sections.
The harsher the terrain, the more likely track equipment is required. Rubber tire earth-moving is extremely unstable, particularly when operated horizontal to a slope. Rubber tire equipment is far more stable when driven perpendicular to a slope. Track equipment is considerably more stable than rubber tire equipment regardless of the angle taken to a slope. Track equipment is far safer in that regard.
The larger the piece of equipment, the more powerful the engine is generally a reliable rule of thumb. That is not always the case, however. While having too much power is not a problem, a piece of equipment without adequate power is.