Device for coupling a barge unit to a pusher-tug for sea transport

摘要

A device for coupling a barge unit to a pusher-tug for sea transport, comprising guiding rollers mounted on the barge on a line perpendicular to the plane of symmetry of the pusher-tug. Two coupling cables pass on the rollers and the cables are connected at one end to shock absorbers at the stern portion of the tug and at opposite ends to hydraulic power devices at the bow portion of the tug. The cable has an inclination angle alpha 1 with respect to the symmetry plane of the tug at the connection with the shock absorber and an inclination angle alpha 2 at the connection with the hydraulic power devices. The angles are selected such that for a preload in the cable equal to force P developed by the hydraulic power devices, the difference between P cos alpha 1 and P cos alpha 2 is at least equal to one-half of the force tending to separate the tug and the barge. Each shock absorber has a stroke equal to the difference in the length of the cable at extreme positions of the tug as determined by the pitching and heaving amplitude of the tug.