Apparatus for leveling subsea structures

Abstract

A leveling apparatus is lowered onto a structure, such as a subsea template, having one or more latching receptacles secured thereon and through which a pile has been driven into the ocean floor. The apparatus engages the open end of the pile and releasably latches onto the receptacle. The apparatus has a lift frame at its upper end, a landing ring below the lift frame, a cylinder frame below the landing ring, and a latch frame below the cylinder frame. The lift frame is connected to the latch frame by vertical stabilizer columns secured to the lift frame and connected at their lower ends to latches in the latch frame. The landing ring is slidably mounted on the stabilizer columns and hydraulic lift cylinders secured to the cylinder frame have their rod ends secured to the housing of the latch frame. When the apparatus is suspended by rigging, the landing ring and lift frame are spaced vertically apart and after the landing ring has been engaged on the pile, the rigging goes slack, and the upper lift frame moves vertically downward. The hydraulic cylinders are extended until the latches travel past a load shoulder in the receptacle and are then retracted to positively lock the latches on the receptacle load shoulder. Continued retraction raises the receptacle and connected structure to a desired position so the structure may be secured to the pile. The apparatus is removed by extending the cylinder rods to raise the lift frame and release the latches or by tugging on the lift frame with the rigging.