| 摘要 |
<p>A quay side container crane for loading and unloading containers onto and from a ship moored against a quay comprises a boom (8) able to span across the ship, a crab able to travel along that boom, and hoisting means for containers suspended from the crab. The boom is supported by a mobile supporting structure (10) on the quay and by a floating supporting structure (9) on the seaward side of the ship. The land based supporting structure has an extensible tower whereby the boom may be kept horizontal. The floating supporting structure comprises two independently manoeuverable barges (17, 18) able to be secured end to end for travelling and side by side for crane operation. One barge carries a first tower (12) supporting the boom in a manner enabling the boom to move longitudinally of itself relative to the first tower and the other barge carries an auxiliary tower (13) supporting the boom but essentially fixed thereto. The first tower comprises an inner column (28) standing upon a self-aligning thrust bearing which column is kept upright but left free to rotate for slewing of the boom by a surrounding frame (29) supporting the column by means of a plurality of elastomeric energy absorbing buffers which damp out swaying movement of the column.</p> |
