Abstract: A crane has a hollow substantially cylindrical load trolley supporting a girder and a support arrangement for the girder. A trolley track device is positioned on the outside of the hollow cylindrical girder for traversing a load along the girder means. A load trolley is supported upon the trolley track with the trolley track being arranged so that a line of action of a load force is applied tangentially to the hollow cylindrical girder. A hogging arrangement is mounted towards the base of the hollow cylindrical girder. The hogging arrangement includes a tensioning member extending the length of the girder.

Abstract: A hydraulically operated crane of either the jib or bridge type with the hoist block supported from a trolley movable along the support structure provided by the jib or bridge. The rope and sheave system to control the lifting and lowering of the hoist block provides a balanced fleet through system and the actuating power for the system is provided by a special hydraulic multiplying linear motor mounted in the jib or bridge. The arrangement of the sheaves is such that movement of the multiplying linear motor causes travel of the hoist rope to be balanced about the hoist block with the rope taken in or let out evenly over the trolley sheaves.