BILGE KEEL OF SEMI-DISPLACEMENT SHIP (VERSIONS) Russian patent published in 2013 - IPC B63B3/44 B63B39/06 

FIELD: transport.

SUBSTANCE: invention relates to ship building. Proposed keel is available in three versions. In compliance with first version, bilge keel comprises wall formed by longitudinal sheet (strip) or section links arranged at hull bilge curves, one on every side. Liner (for example, rod of tubular, bar, bulb iron or corner sections) are welded to wall free edge. Bow end of bilge keel features gradual decrease in wall height, said wall being composed of strip with rounded free edge of increased height exceeding that of wall at keel midsection by 1.3-2.1 times. Wall free edge liner extends toward fore body in the limits of keel wall constant height. In compliance with second version, bilge keel differs from known designs in that keel end wall comprises reinforcement in fore body free edge zone composed of a streamlined part rigidly jointed to keel wall with lined free edge. In compliance with third version, bilge keel free wall edge liner is located primarily in the limits of its constant height. Note here that at front parts of tubular, bar or bulb iron sections or directly at keel wall plate, longitudinal strips are arranged perpendicular to keel wall on length of about 0.7-2.0 of keel wall height, strip width making 0.1-05 of wall height.

EFFECT: reduced vibrations, higher efficiency of pitch damping.

3 cl, 5 dwg