Boom Crane
Boom Crane
a slewing wall-bracket crane with a stationary or movable boom. The boom frame is anchored in upper and lower supports and is most frequently in the form of a triangulated truss, with guide pulleys for a hoisting rope fastened to its upper end. It also has mechanisms for lifting and rotating loads. Boom cranes with a movable boom are equipped with a mechanism for changing the boom. The lifting capacity of boom cranes is usually not great (less than 5 tons); because of this only small plants and shops are equipped with them.