Saipem Limited

Pasquale Brando

Giovanni Rosa

Antonio Silvestri

Giuseppe Daghetti

Claudio Morelli

A semi-submersible pipelaying watercraft is disclosed, which is particularly suitable for operating under particularly hostile marine environments, said watercraft comprising a composite ramp of special construction for launching the pipe to be laid, a system for determining the craft's position and a control system, governed by electronic computers for automatically positioning the craft. An internal inclinable ramp is coactively combined with an external ramp and the internal ramp is equipped with a locking system and with a displacing system, hydraulic controls being provided for moving both the internal and external ramps. The electronic computers are two and one of them makes the calculations for determining the design parameters, whereas the other computer receives the actual data provided by the several sensors mounted aboard and processes them.

Semi-submersible pipelaying craft equipped for laying pipes on sea beds,

This invention relates to an improved method for rapidly laying a pipeline in deep water by an anchored floating means. The rapid laying is obtained by varying the forces exerted by winches mounted on the floating means in such a manner as to impart a rapid movement to the floating means, in the longitudinal direction of laying, for a distance equal to the length of the piece of pipe added to the free end of the pipeline to be laid. Before termination of the rapid movement there is applied to the floating means a compensating force, whose direction, sense and intensity are such that, together with the forces exerted by the winches, said compensating force opposes moment by moment the central elastic force which induces a damped oscillatory motion in the floating means. This oscillation is thus eliminated or drastically and rapidly dampened.

Method for rapidly laying a pipeline in deep water by an anchored laying

A closed end of a pipeline submerged in water to a depth of upwards of about 125 meters if lifted to the surface and recovered by exerting a pull on said end by means of a capstan mounted on a floating pontoon and having an adjustable tension, and by simultaneously exerting a lift on said pipeline at said end and at least one point spaced from said end by means of a set of cranes mounted on said pontoon, at least one of said cranes being mounted for movement on said pontoon and adapted to exert a lift at said end of the pipeline, and at least one other crane being fixed to said pontoon and adapted to exert a lift at said end and at the point spaced from said end of the pipeline, so that the length of the pipeline between said point and said end may be removed from the balance of the pipeline.

Process and system for lifting submarine pipelines

A catamaran, adapted for use in laying a submerged pipeline, is provided with a slidable support for the pipeline, including a slightly inclined ramp integral with the awning deck of the catamaran for carrying out the operations for building the pipeline, a moveable stinger extending from the rear end of the catamaran, and an intermediate pipeline supporting element having its bow end hinged to the stern end of the ramp and its stern end pivotally hooked to the front end of the stinger. The stern end of the intermediate pipeline supporting element may be raised or lowered so that its angle of inclination may be varied and it may be locked in position at a selected angle of inclination through a castle-shaped member located abaft the catamaran and including two side frames fixed to the awning deck of the catamaran so that they straddle the intermediate pipeline supporting element and their lower ends are submerged. The frames are provided with vertically spaced pairs of opposed holes for the reception of check pins extending through holes located in the sides of the intermediate pipeline supporting element at its stern end.

Growing community of inventors

San Donato Milanese, Italy

Pasquale Brando