Roadheaders are underground crawler-type excavating machines with a boom-mounted cutting drum used for tunneling and mining operations. They can be fitted with various excavation attachments, including shovels, conveyors, booms, and roof bolters.
Roadheaders may feature one of two types of cutting drums, which are used to cut through hard rock and soil. Longitudinal drums are conical heads, fitted with metal teeth, which rotate parallel to the boom's axis. Conversely, transverse drums rotate perpendicular to the boom's axis and may include multiple cylindrical cutting heads.
A longitundinal (left) and transverse roadheader.
Image credit: Sanyi | MEKTUNNEL