Abstract: A telescopic boom of a crane comprising a base element adapted for support on a turret of the crane, and a plurality of telescopic elements slidably engaged within one another and within the base element. The elements have a polygonal cross-section, each element having a lower or inner compression leg of inverted V-shape which opens downwardly and falls the load. First guide shoes are mounted on each telescopic element on the upper or outer leg thereof, bearing against the surrounding element, and second guide shoes are mounted on each branch of the inverted V-shaped inner leg also bearing against the surrounding element.

Abstract: A high capacity crane which has a wheeled or tracked chassis carrying a support structure rotatable about a vertical axis and including a jib and a counter-jib. An arcuate beam centered on the axis of rotation is anchored to the ground and carries a connector movable along the beam to which connector the counter-jib is in turn anchored.