A system to convey a fluid, in particular a fluid containing hydrocarbons, has a first pipeline, which is made of an electrically conductive material and has an internal diameter; a second pipeline, which is made of an electrically conductive material, has an external diameter smaller than the internal diameter, and is placed inside the first pipeline at a distance from the first pipeline so as to form an annular gap between the first and second pipeline; an electrically conductive layer placed in the annular gap at a distance from the first pipeline; an electrically insulating layer placed between the second pipeline and the electrically conductive layer; and a power source to apply an electrical potential difference between the second pipeline and the electrically conductive layer.

A system to convey a fluid, in particular a fluid containing hydrocarbons, has a first pipeline, which is made of an electrically conductive material and has an internal diameter; a second pipeline, which is made of an electrically conductive material, has an external diameter smaller than the internal diameter, and is placed inside the first pipeline at a distance from the first pipeline so as to form an annular gap between the first and second pipeline; an electrically conductive layer placed in the annular gap at a distance from the first pipeline; an electrically insulating layer placed between the second pipeline and the electrically conductive layer; and a power source to apply an electrical potential difference between the second pipeline and the electrically conductive layer.

A pipe for heating a cryogenic liquefied gas, the pipe having a peripheral wall including a ply of one or more electrically conductive carbon fibers, the ply being configured and electrically connectable to a power supply such that the one or more carbon fibers are heated when power is supplied to the ply.

A pipe for heating a cryogenic liquefied gas, the pipe having a peripheral wall including a ply of one or more electrically conductive carbon fibers, the ply being configured and electrically connectable to a power supply such that the one or more carbon fibers are heated when power is supplied to the ply.

A heated subsea pipe and process for transporting fluids, includes a plurality of pipe sections each having a transport tube for receiving the fluids, an electrically insulating inner layer arranged around the transport tube, a sealing tube made of electrically conductive material arranged around the electrically insulating inner layer, a thermally insulating outer layer arranged around the sealing tube. The transport tube is electrically connected to the sealing tube at each of the two ends of the pipe. The pipe includes two electrical cables connected to an electric generator and, to the transport tube and to the sealing tube of the pipe at a point situated between the two ends of the pipe to produce two parallel electrical circuits each traversed by an electric current for heating the transport tube of the pipe by Joule effect.

A heated subsea pipe and process for transporting fluids, includes a plurality of pipe sections each having a transport tube for receiving the fluids, an electrically insulating inner layer arranged around the transport tube, a sealing tube made of electrically conductive material arranged around the electrically insulating inner layer, a thermally insulating outer layer arranged around the sealing tube. The transport tube is electrically connected to the sealing tube at each of the two ends of the pipe. The pipe includes two electrical cables connected to an electric generator and, to the transport tube and to the sealing tube of the pipe at a point situated between the two ends of the pipe to produce two parallel electrical circuits each traversed by an electric current for heating the transport tube of the pipe by Joule effect.

Disclosed herein is a pipe assembly comprising: a pipe with an electrically conductive wall with a thermally conductive outer coating; a first electrical connector that is arranged in electrical contact with the wall of the pipe; and a second electrical connector that is arranged in electrical contact with the wall of the pipe; wherein the first and second electrical connectors are arranged to support the flow of an electrical current through the wall of the pipe to thereby heat the wall of the pipe; and in use, the pipe is arranged to allow cooling of the outer surface of the wall of the pipe by the surrounding environment of the pipe when the outer surface of the wall of the pipe is hotter than its surrounding environment. Advantageously, embodiments provide an effective, efficient and less expensive technique for heating the pipe in order to remove deposits for the inner walls of the pipes. Applications include the subsea application of cooling oil well products for cold flow.

Disclosed herein is a pipe assembly comprising: a pipe with an electrically conductive wall with a thermally conductive outer coating; a first electrical connector that is arranged in electrical contact with the wall of the pipe; and a second electrical connector that is arranged in electrical contact with the wall of the pipe; wherein the first and second electrical connectors are arranged to support the flow of an electrical current through the wall of the pipe to thereby heat the wall of the pipe; and in use, the pipe is arranged to allow cooling of the outer surface of the wall of the pipe by the surrounding environment of the pipe when the outer surface of the wall of the pipe is hotter than its surrounding environment. Advantageously, embodiments provide an effective, efficient and less expensive technique for heating the pipe in order to remove deposits for the inner walls of the pipes. Applications include the subsea application of cooling oil well products for cold flow.

An assembly comprising an end-fitting and an unbonded flexible pipe comprising several layers. The unbonded flexible pipe has an end-part entering the end-fitting at the front end and the layers of the unbonded flexible pipe being terminated in the end-fitting. The unbonded flexible pipe further comprises a first electrically conductive layer and a second electrically conductive layer, where the first electrically conductive layer is electrically insulated from the second electrically conductive layer. The end-fitting comprises a first electric zone electrically connected with the first electrically conductive layer, and a second electric zone electrically connected with the second electrically conductive layer, the first electric zone is electrically separated from the second electric zone, and the end-fitting comprises a third electric zone, the third electric zone being electrically separated from first electric zone and the second electric zone.

An assembly comprising an end-fitting and an unbonded flexible pipe comprising several layers. The unbonded flexible pipe has an end-part entering the end-fitting at the front end and the layers of the unbonded flexible pipe being terminated in the end-fitting. The unbonded flexible pipe further comprises a first electrically conductive layer and a second electrically conductive layer, where the first electrically conductive layer is electrically insulated from the second electrically conductive layer. The end-fitting comprises a first electric zone electrically connected with the first electrically conductive layer, and a second electric zone electrically connected with the second electrically conductive layer, the first electric zone is electrically separated from the second electric zone, and the end-fitting comprises a third electric zone, the third electric zone being electrically separated from first electric zone and the second electric zone.