Abstract: A propulsive air stream deflecting apparatus for an air cushion vehicle is provided on the hull of the air cushion vehicle for arcuately deflecting the propulsive air stream from the open rear end of the air duct, mounted to the hull. The deflecting mechanism provides a steering thrust to the air cushion vehicle. The deflecting mechanism is pivotable about a vertical pivot mounted to the hull between a propulsive thrust producing position, where the deflecting mechanism is located away from the propulsive air stream issuing from the rear open end of the air duct, and a forward thrust producing position where the deflecting mechanism fully covers the rear open end of the air duct for deflecting the propulsive air stream to create the forward thrust to the hull.

Abstract: A propulsion air stream deflecting apparatus for an air cushion vehicle having a hull, an air duct mounted on the hull and a propeller fan, includes a plurality of rudders, each mounted on the hull adjacent to the rear open end of the duct for pivotal movement about a vertical axis. The rudders are adapted to close the rear open end of the air duct. A rudder control mechanism is operatively connected to the rudders for controlling the pivotal movement of the rudders to selectively provide a propulsion thrust and a steering thrust to the hull and to provide a closed position in which the rear open end of the air duct is closed by the rudders. A flap is pivotably mounted at the rear end thereof to the duct such that the flap closes an opening, formed at the rear end of the air duct, at a closed position thereof where the inner face of the flap is substantially flush with the inner surface of the air duct.

Abstract: An apparatus for continuous production of seam-welded steel tubing is proposed. The apparatus includes a series of shaping rolls for shaping a strip taken out from a strip coil into a tubular intermediate product, the roll series including a finpass roll group. The tubular product is subjected to seam welding under the action of a seam welder. Before arrival at the welder, a substantial main part of the preformed tubing with exception of opposing edge zones thereof is subjected to heating by a heater compensate for excess compressive stresses induced in the edge zones, while these zones are subjected to cooling by a cooler for avoiding otherwise formation of disadvantageous edge wavings which would otherwise occur.