The closed chock is made according to the standard of ISO 13729. The type of the mooring chock is normally applied for the ship which uses wire ropes. The radius of the surface was designed based on the bending ratio of rope through the chock of not less than twelve times the wire rope diameter. The foundation of the closed chocks shall be determined by considering the actual load direction. The foundation and welding connections to the hull shall be guaranteed reliable transmission of the maximum loading to hull construction without any plastic deformation or cracks. The ISO13729 chocks can also be classified into two types by its installation site including deck-mounted closed chock and bulwark mounted one.
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