Abstract:
A system and method for securely cradling a subsea pipeline is claimed that lands on one side of the pipeline, is embedded into the sea floor, reaches under the pipeline, positions the cradling structure, and then lifts the pipeline. The system typically comprises a gravity driven pile based device, comprising a pile tower, a roller carriage assembly, and a jacking assembly that engages the roller carriage assembly and pile tower rails.
Abstract:
A method of securing a pipeline to the bed of a body of water includes moving an underwater vehicle selectively, on the bed of the body of water, along the pipeline; transporting a plurality of fastening devices on the underwater vehicle; and driving each fastening device partly into the bed of the body of water, close to the pipeline, by a handling device mounted on the underwater vehicle, to confine the pipeline between the bed of the body of water and the fastening device.
Abstract:
For regulating the lateral buckling of a section of pipe, at least one device permanently applies a force to a point on the section of pipe. The force is preferably applied substantially horizontally and perpendicular to the axis of the pipe. Preferably, two of the devices that apply equal and opposing forces are positioned at a distance from each other along the section of a pipe. Each device comprises a clamp, a cable, a return device and a buoy or a weight.
Abstract:
A flowline for hydrocarbon which is capable of being reeled and which is unreeled for being laid on the seabed using the reeled lay method is comprised of successive pipe sections having opposing ends which are joined by an anchor collar that is butt welded to the opposing ends. The pipe sections have a jacket on the exterior of the pipe sections, but the pipe sections are able to be reeled. Anchor collars are affixed by butt welding between the ends of adjacent pipe sections. Each anchor collar has a fixture or protrusion radially outward which has an outer diameter less than or at least not more than the outer diameter of the pipe section jacket. The flowline has the same inner diameter at the pipe sections and the collar, and the pipe has the same outer diameter as the collar, while the protrusion protrudes outward from the exterior of the collar. The flowline is anchored on the seabed by unreeling it from a spool, applying a clamp to the collar before delivering it to the seabed, and anchoring the clamp to the seabed. The jacket may expose the fixture or protrusion or may initially cover it and be removed to enable the clamping.
Abstract:
Gas Subsea Transmission System (GSTS) is a new method for transferring large quantities of natural gas between marine distances through the oceans. Its purpose is to provide a safer, faster and more financially advantageous alternative to gas transmission via LNG.The GSTS's main part is a Submersible Suspension Pressure-equaliser Pipeline (SSPP). It is a long pipe with a large diameter which has a high capacity of gas transmission. This pipe is kept submersible and suspended in deep waters by its special mooring system. It is made from steel pipe which is reinforced by internal concrete rings.The basic concept of SSPP is to cancel the internal pressure of the gas pipeline with the external hydrostatic water pressure by varying the pipe environment. These conditions lead to the possibility of a large diameter pipeline resulting in efficient, high capacity gas transmission. SSPP mooring system is able to change the pipe level to the right depth base on the changes in gas pressure and equalise the external and internal pressures.The GSTS has offshore stations that separate the SSPP into shorter segments. The pipe can be operated, maintained, installed and inspected from these points. During normal operation, these offshore stations are capable of staying submerged under water. This design feature means that they would be protected from adverse surface conditions.
Abstract:
The bracket comprises an upright tube and a cleat connected to one side of the tube. The cleat has a pair of horizontal, transversely extending horns protruding from the tube. In use, a pair of the brackets are pivotally mounted on the upper ends of the shafts of embedded screw piles bracketing a pipeline. A flexible tie-down strap, having loop ends, extends across the pipeline. The loop ends each releasably engage one of the brackets. Each loop end extends over the bracket tube and is trapped beneath the cleat, so as to bear against the side surface of the tube lower end. The loop end and bracket can readily be engaged or disengaged in the field.
Abstract:
A lower portion of a subsea oil delivery hose is held taut between bouyant devices installed on the hose and a stationary point on the subsea floor. A portion of the lower part of the hose, connected to the stationary point, has a curved portion that is concave in the direction of a wellhead to which the hose is connected.
Abstract:
A method of anchoring a line, such as a pipeline, to a support, and in particular a sea-bed, comprises the steps, at each anchoring point, of drilling holes in the support on both sides of the line, bedding piles in these holes, passing at least one saddle clamp around the line, securing the ends of the saddle clamp to the piles, and injecting a filling material, which may be a settable material, into an inflatable body arranged between the line and the saddle clamp.Devices for carrying out the method are also described.
Abstract:
A new and improved system, apparatus and method for performing operations on the floor of the sea or other underwater locations utilizes a combination of tension devices for maintaining work bodies in desired positions while also permitting viewing of such underwater operations by remote control television camera or other operations.