Abstract:
Tong apparatus operated oleopneumatically for lifting a submerged pipeline either directly by a frogman or by an operator on a pontoon or vessel. The apparatus includes a pair of jaws controlled by a double acting cylinder with two pistons. The cylinder has a body pivotally connected to the upper end of one jaw and has an active chamber wherein a first piston with a wide cross-section slides, while a second piston having a small crosssection is pivotally connected to the upper end of the other jaw and slides coaxially as to the first piston in a second active chamber provided by the wide cross-section of the said first piston. With the present invention small quantities of oil are used in causing the jaws to approach and to grasp and lift the pipeline. The relatively wide shifting required for approaching the jaws to the pipeline to be grasped and lifted is obtained by acting oleopneumatically into the said second active chamber against the piston having a small cross-section, which involves the use of a small quantity of oil. The pipeline grasping operation, which requires a relatively small shifting and small oil consumption, is then carried out by acting oleopneumatically into the first said active chamber against the said first piston having a wide cross-section.
Abstract:
This invention relates to an apparatus for supporting pipes suspended over depressions in the sea bed, including those situated at great depth, and to the method for installing it on the sea bed. The apparatus according to the invention consists of a completely recoverable service module and a support mobile which serves to support the pipe and remains fixed on the sea bed, said modules being connected together in such a manner that they can be separated by simple controls from the depot ship. The method according to the invention comprises in turn a number of operating steps, through which the entire apparatus is initially lowered and positioned on the sea bed and the service module is then recovered by the depot ship.
Abstract:
Improved apparatus is provided for forming or erecting concrete loaded supporting means for supporting undersea pipelines at all depths and in the presence of undulating sea beds characterized by providing suspendable service module or frame means provided with pumpable concrete carrying means, vertical articulated positioning arm means mounted at one end to one end of the service module means with the one end thereof having means for releasably engaging concrete receiving pipe support module means, means for actuating the articulated positioning arm to place the support module beneath the undersea pipe to be supported, means operatively associated with the vertical articulated positioning arm and the concrete carrying means for transferring cement from the concrete carrying means to the support module.
Abstract:
For lifting from deep sea beds a pipeline trunk, a device is disclosed which is composed by a compact framework of square outline which supports a sealing and pulling head and paired jaw assemblies having sloping surface seats to engage the outer surface of the pipe to be lifted, said jaws being actuated by hydraulic and pneumatic motive means so as to grip the pipe surface firmly. A pipe-cutting device is also provided, which has two discrete cutting units, and the sealing and pulling head is removable from said frame and can be both slid and rotated as to position it correctly coaxially with the pipe trunk.