Direct electric pipeline heating

• Main Authors: BASS; RONALD MARSHALL, LANGNER; CARL GOTTLIEB
• Format: Patent
• Language: English
• Published: 07.11.2000
• Edition: 7
• Subjects: BLASTING; EARTH DRILLING; EARTH DRILLING, e.g. DEEP DRILLING; ELECTRIC HEATING; ELECTRIC LIGHTING NOT OTHERWISE PROVIDED FOR; ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR; ELECTRICITY; ENGINEERING ELEMENTS AND UNITS; FIXED CONSTRUCTIONS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVEFUNCTIONING OF MACHINES OR INSTALLATIONS; HEATING; JOINTS OR FITTINGS FOR PIPES; LIGHTING; MEANS FOR THERMAL INSULATION IN GENERAL; MECHANICAL ENGINEERING; MINING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR ASLURRY OF MINERALS FROM WELLS; PIPES; SUPPORTS FOR PIPES, CABLES OR PROTECTIVE TUBING; THERMAL INSULATION IN GENERAL; WEAPONS

A system for direct electric heating of a subsea pipeline is disclosed in the form of a pipe-in-pipe flowline having an electrically conductive outer carrier pipe and an electrically conductive inner pipe or flowline arranged longitudinally, substantially concentrically within the outer pipe. An annulus is defined between the inner and outer pipes and a pipe insulating joint assembly structurally joins, but electrically insulates, the inner and outer pipes at a first end of the subsea pipeline. A power input provided on the surface facilities is electrically connected across the inner and outer pipes at the first end of the pipeline, and an electrical pathway completes the circuit by connecting the inner and outer pipes at the second end of the pipeline.