Trenchers are a type of construction equipment specifically designed for the excavation of terrain for the purpose of constructing a trench. These earthen depressions are characterized with measurements that are deeper than its width, and are primarily used for the burial of infrastructure such as pipelines, utility mains, drainage and sewer systems, and power and telephone lines. Placing these components subsurface protects them from severe weather and misfortune, while also contributing to a better surface aesthetic.
Ground-based versions are either trencher machines which are for trenching-only operations, or attachments for skid-steer or other multi-use utility vehicles. To excavate trenches on the sea floor, trenching operations are conducted by a trenching barge (in shallow waters) or by remotely-monitored vehicles, linked to a surface vessel, which crawl the ocean floor (in deeper waters).
While there are several methods to construct a trench, there are two primary mechanisms which are commonly utilized by trenching equipment. Wheel trenchers implement a series of excavating buckets placed around the circumference of a driven wheel. Ladder trenchers place excavation buckets around the periphery if a roller chain. Ladder trenchers are capable of significantly larger and deeper trenchers, but the maintenance and expense of ladder trenchers is considerably more.
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