Making subsea pipelines ready for electrical heating
AssigneeShell Oil Company
InventorsFrans F. Kopp, Ronald M. Bass
Life of this patent
Estimating the term…
Abstract
Apparatus and method are provided for connecting electrical power for heating subsea pipelines after the pipeline is deployed. Electrical connections may be made subsea using wet-mateable connectors. The electrical power may be supplied from a boat or may be supplied from a host structure. A Remotely Operated Vehicle may be used to make the subsea electrical connections. Single Heated Insulated Pipes, Pipe-in-Pipe, heat tracing and other configurations for heating may be employed. The deployment of cables and other equipment for heating may be delayed until a need or potential need for heating or the probable locations of impediments to flow are identified in the subsea pipeline.
Claims43
Apparatus for electrically heating a segment of a subsea pipeline, the segment having a first end and a second end, comprising:
- an inner pipe and an outer concentric pipe forming an annulus in the segment to be heated;
- electrical connections between the inner and the outer concentric pipe at the first and second ends of the segment;
- a midline connector having electrical connections to the inner and to the outer concentric pipe, the midline connector being disposed at a selected location intermediate the first and second ends;
- and
- a wet-mateable electrical connector electrically connected to the midline connector.
Apparatus for electrically heating a segment of a subsea pipeline, the segment having a first end and a second end, comprising:
- a flowline pipe covered with a layer of electrical insulation so as to insulate the pipe from surrounding seawater in the segment;
- electrical connectors to the pipe at the first and the second end of the segment;
- and
- a wet-mateable connector connected to at least one of the electrical connectors to the pipe.
Apparatus for electrically heating a segment of a subsea pipeline, the segment having a first end and a second end, comprising:
- a flowline pipe covered with a layer of electrical insulation so as to insulate the pipe from surrounding seawater in the segment;
- electrical connectors to the pipe at the first and the second end of the segment;
- a wet-mateable connector connected to at least one of the electrical connectors to the pipe;
- and
- a toroidal transformer disposed at a selected location intermediate the first end and the second end and having an electrical cable, the cable being attached to the wet-mateable connector.
A method for electrically heating a selected segment of a subsea pipeline, the segment having electrical conductors for supplying electrical power for heating the segment, comprising:
- electrically connecting a wet-mateable connector to at least one electrical conductor used for supplying power to the segment before the pipeline is deployed;
- deploying the pipeline and after the pipeline is deployed forming an electrical circuit including the step of connecting the wet-mateable connector;
- providing a source of power;
- and
- connecting the source of power to the circuit and applying electrical power to heat the selected segment of the pipeline.
A method for electrically heating a selected segment of a subsea pipeline, the segment having a first end and a second end, an inner pipe and an outer concentric pipe forming an annulus in the segment, electrical connections between the inner and the outer concentric pipe at the first and second ends of the segment, and a midline connector having electrical connections to the inner pipe and to the outer concentric pipe, the midline connector being disposed at a selected location intermediate the first and second ends, and a wet-mateable electrical connector electrically connected to the midline connector, comprising:
- providing a source of electrical power at a selected voltage;
- lowering the source of power to the vicinity of the wet-mateable electrical connector;
- connecting the source of power to the wet-mateable connector and applying electrical power to heat the selected segment of the pipeline.
A method for electrically heating a selected segment of a subsea pipeline, the segment having a first end and a second end and a flowline pipe being covered with a layer of electrical insulation so as to insulate the pipe from surrounding seawater, electrical connectors to the pipe at the first end and the second end of the segment and wet-mateable connectors connected to the electrical connectors to the pipe, comprising:
- providing a source of electrical power at a selected voltage;
- lowering the source of electrical power to the vicinity of at least one of the wet-mateable connectors;
- and
- connecting the source of power to the wet-mateable connectors and applying electrical power to heat the selected segment of the pipeline.
A method for electrically heating a selected segment of a subsea pipeline, the segment having a first end and a second end and a flowline pipe being covered with a layer of electrical insulation so as to insulate the pipe from surrounding seawater, electrical connectors to the pipe at the first end and the second end of the segment and a toroidal transformer around the flowline pipe at a selected location intermediate the first end and the second end of the segment, the toroidal transformer having a wet-mateable connector, comprising:
- providing a source of electrical power;
- electrically inter-connecting the electrical connectors to the pipe at the first end and the second end;
- lowering the source of electrical power to the vicinity of the toroidal transformer;
- and
- connecting the source of power to the wet-mateable connector of the toroidal transformer and applying electrical power to heat the selected segment of the pipeline.
Dependencies are inferred from the claim text.