A trencher is piece of construction equipment used to dig trenches, typically for laying pipes or cable, or for drainage. Trenchers may range in size from walk-behind models, to attachments for a skid loader or tractor, to very heavy tracked
Trenchers come in different sizes and may use a different digging implement, depending on the required width and depth of the trench and the hardness of the surface to be cut.
Wheel trenchers may be mounted on tracks or rubber tires, and utilize a number of buckets mounted on a wheel that moves in a circular motion to excavate material. Wheel trenchers are the fastest method of excavating and are cheaper to operate and maintain than chain type trenchers.
A track trencher with a digging chain
A big chainsaw trencher
A chain trencher cuts with a digging chain that is driven around a rounded metal frame, or boom. It resembles a giant chainsaw. This type of trencher can cut ground that is too hard to cut with a bucket-type excavator.
The angle of the boom can be adjusted to control the depth of the cut. To cut a trench, the boom is held at a fixed angle while the machine creeps backward.
A rockwheel is a toothed metal wheel—effectively a giant circular saw. Rockwheels can cut harder ground than a chain trencher, including cutting through solid stone. They are also used to cut
for road maintenance and to gain access to utilities under roads.
The teeth on a rockwheel are removable and made of high strength steel (
, tool steel or high speed steel) or tungsten. When the machine is under heavy use, the teeth may need to be replaced frequently, even daily.
A portable trencher machine in operation
Landscapers and lawn care specialist may use a portable trencher to install landscape edging and irrigation lines. They may also be used to install utility connections just beneath the surface such as coaxial cables. These machines are lightweight (around 200 pounds) and are easily maneuverable compared to other types of trenchers. The cutting implement may be a chain, or a blade similar to a rotary lawn mower blade oriented so that it rotates in a vertical plane.
A trencher may be combined with a drainage pipe or geotextile feeder unit and backfiller, so drain or textile may be placed and the trench filled in one go.