A subsea energy storage installation comprises a pumped-storage system having pumping and hydropower generation components for, selectively, converting electricity into potential energy by expelling water from within a tank into the surrounding sea and for generating electricity from an incoming flow of water re-entering the tank under hydrostatic pressure. The tank comprises at least one elongate rigid pipeline that may be lowered to the seabed as part of a towable unit or laid on the seabed as a pipe string launched from a surface vessel.

A long steel pipe for reel-lay installation formed of electric resistance welded (ERW) steel pipes and having high buckling resistance and a method for producing the long steel pipe for reel-lay installation are provided. The long steel pipe is formed by successively butt-joining longitudinal ends of the ERW steel pipes by girth welding so that girth welds are formed. The ERW steel pipes are successively butt-joined in the pipe longitudinal direction such that the 0 o'clock cross-sectional position or the 6 o'clock cross-sectional position of one of adjacent ERW steel pipes faces an area from the 2 o'clock cross-sectional position to the 4 o'clock cross-sectional position or an area from the 8 o'clock cross-sectional position to the 10 o'clock cross-sectional position of the other of the adjacent ERW steel pipes.

A process for the manufacture, assembly and continuous construction of tubular sections made of steel or polymer in individual pipelines with gradual movement that is designed to mechanize and automate a process substantially eliminating or mitigating existing inefficiencies and risks, considerably reducing the time vessels need to be moored at piers while paying extremely expensive daily rates, increasing the quality of welds, inspections and the entire process The process including inside the manufactured unit one or more weld cabins and a series of support devices with synchronized driven and free wheels that carry the pipe segments while simultaneously enabling movement of the entire stalk without external interference, following the joining of several pipe segments (welded together), of variable length, in which the embodiments provided in the present invention enable each stalk to be approximately 1.2 km long or longer.

A process for the manufacture, assembly and continuous construction of tubular sections made of steel or polymer in individual pipelines with gradual movement that is designed to mechanize and automate a process substantially eliminating or mitigating existing inefficiencies and risks, considerably reducing the time vessels need to be moored at piers while paying extremely expensive daily rates, increasing the quality of welds, inspections and the entire process The process including inside the manufactured unit one or more weld cabins and a series of support devices with synchronized driven and free wheels that carry the pipe segments while simultaneously enabling movement of the entire stalk without external interference, following the joining of several pipe segments (welded together), of variable length, in which the embodiments provided in the present invention enable each stalk to be approximately 1.2 km long or longer.

A method of positioning an end of a pipeline on a subsea structure includes the steps of: (a) providing a channel on the subsea structure, the channel having an open end adjacent to a receptacle on the subsea structure, (b) providing a pipeline, (c) attaching a connector to an end of the pipeline, (d) laying the end of the pipeline with the connector attached into the channel, and (e) pulling the pipeline end along the channel such that the connector exits the open end of the channel and is received by the receptacle. A channel is used in the method and a subsea structure is used wherein the channel is provided on the upper surface of the subsea structure.

A method of positioning an end of a pipeline on a subsea structure includes the steps of: (a) providing a channel on the subsea structure, the channel having an open end adjacent to a receptacle on the subsea structure, (b) providing a pipeline, (c) attaching a connector to an end of the pipeline, (d) laying the end of the pipeline with the connector attached into the channel, and (e) pulling the pipeline end along the channel such that the connector exits the open end of the channel and is received by the receptacle. A channel is used in the method and a subsea structure is used wherein the channel is provided on the upper surface of the subsea structure.

The present invention is a hydraulic excavation and delivery device capable of hydraulically removing soil overburden from a buried structure, like a pipeline, and delivering an article, such as an electro-mechanical connector for attachment to the buried structure. Hydraulic excavation is achieved by directing a stream of fluid at soil adjacent to and inside an open bottom region of the device to simultaneously dislodge adjacent soil, suspend dislodged soil in the accumulating fluid and form a pit that the device may fit within. Delivery of article is achieved by: (1) loading an article into the tool; (2) advancing the device toward the buried structure by deepening the pit without significant failure (slumping or sagging) of the pit walls until a portion of the buried structure is exposed and within the device; (3) landing the device on the exposed portion of the structure; (4) fixing the article to the exposed portion of the structure; and (5) releasing the article from the device.

The present invention is a hydraulic excavation and delivery device capable of hydraulically removing soil overburden from a buried structure, like a pipeline, and delivering an article, such as an electro-mechanical connector for attachment to the buried structure. Hydraulic excavation is achieved by directing a stream of fluid at soil adjacent to and inside an open bottom region of the device to simultaneously dislodge adjacent soil, suspend dislodged soil in the accumulating fluid and form a pit that the device may fit within. Delivery of article is achieved by: (1) loading an article into the tool; (2) advancing the device toward the buried structure by deepening the pit without significant failure (slumping or sagging) of the pit walls until a portion of the buried structure is exposed and within the device; (3) landing the device on the exposed portion of the structure; (4) fixing the article to the exposed portion of the structure; and (5) releasing the article from the device.

The present invention is a hydraulic excavation and delivery device capable of hydraulically removing soil overburden from a buried structure, like a pipeline, and delivering an article, such as an electro-mechanical connector for attachment to the buried structure. Hydraulic excavation is achieved by directing a stream of fluid at soil adjacent to and inside an open bottom region of the device to simultaneously dislodge adjacent soil, suspend dislodged soil in the accumulating fluid and form a pit that the device may fit within. Delivery of article is achieved by: (1) loading an article into the tool; (2) advancing the device toward the buried structure by deepening the pit without significant failure (slumping or sagging) of the pit walls until a portion of the buried structure is exposed and within the device; (3) landing the device on the exposed portion of the structure; (4) fixing the article to the exposed portion of the structure; and (5) releasing the article from the device.

It is described a method of laying a pipeline (1) on a seafloor (2), wherein the method comprises the steps of: —bringing the pipeline to an offshore location using a vessel, —laying the pipeline on the seafloor using the vessel, —defining a first zone (10) surrounding at least a first part length (1′) of the pipeline when laid subsea, wherein the first part length is uncovered, —defining a second zone (20) extending from the first zone, —monitoring the second zone for vessels approaching the first zone, —analysing vessels detected during said monitoring of the second zone, for the purpose of determining whether the vessels can cause harm to the first part length of the pipeline, —for each vessel monitored in the second zone and considered to be able to cause harm to the first part length of the pipeline, informing the vessel about the first zone and/or requesting the vessel not to enter into the first zone.