Patent ID: 8052350

Claim:
A marine pipelaying vessel with a pipeline stinger pivotably connected to said vessel and forming a downwardly directed support for pipeline to be laid, wherein said vessel comprises a stinger suspension assembly between said stinger and said vessel from which said stinger is suspended at least during operation, said stinger suspension assembly including a sacrificial stinger impact absorber adapted to absorb impact energy resulting from a violent stinger motion, and wherein said impact absorber has a first connector member and a second connector member for attaching said impact absorber to said vessel and said stinger, respectively, and wherein said first connector member includes a tubular housing and wherein said second connector member includes a piston within said tubular housing, and wherein said first connector member includes an end cap at one end of said tubular housing, said piston being fixed to said end cap via one or more frangible fixations having a load threshold for breaking, said one or more fixations remaining intact during normal operation of the vessel such that the impact absorber functions as a rigid element in the stinger suspension assembly, and wherein a series of sacrificial members is arranged at intervals in the tubular housing, said sacrificial members being embodied as deformable annular members having an opening therein through which said piston extends, and wherein, upon the violent stinger motion causing a load on the one or more frangible fixations above said load threshold, the frangible fixations break, thus releasing the piston, and said sacrificial members being deformed plastically as said piston moves with respect to the tubular housing.