Abstract: External heating assembly 1 is usable to heat subsea flowline 100 and remediate a blockage in subsea flowline 100 and comprises a predetermined set of heaters 10; one or more conductive layers 20 configured to uniformly distribute heat over an exterior of subsea flowline 100; one or more insulating layers 30 adapted to shield subsea flowline 100, the predetermined set of heaters 10, and conductive layers 20 from ambient seawater temperature; an anchor; and a strength member. The predetermined set of heaters 10 may comprise one or more mineral insulated cables capable of reaching very high temperatures with very little power and minimal controls.

Abstract: External heating assembly 1 is usable to heat subsea flowline 100 and remediate a blockage in subsea flowline 100 and comprises a predetermined set of heaters 10; one or more conductive layers 20 configured to uniformly distribute heat over an exterior of subsea flowline 100; one or more insulating layers 30 adapted to shield subsea flowline 100, the predetermined set of heaters 10, and conductive layers 20 from ambient seawater temperature; an anchor; and a strength member. The predetermined set of heaters 10 may comprise one or more mineral insulated cables capable of reaching very high temperatures with very little power and minimal controls.

Abstract: Coiled tubing may be placed inside a subsea flowline, such as with a subsea insertion tool, to remediate blockages in the flowline subsea. In embodiments, the subsea insertion tool is used to unspool a length of coiled tubing string from a coiled tubing reel and insert the unspooled coiled tubing string subsea into flowline to where a jetting nozzle is positioned proximate a blockage in flowline 120. Fluid is provided, e.g. pumped, from chemical pumping unit 80 to coiled tubing string 100 through to jetting nozzle 110 to remediate the blockage in flowline 120.

Abstract: External heating assembly 1 is usable to heat subsea flowline 100 and remediate a blockage in subsea flowline 100 and comprises a predetermined set of heaters 10; one or more conductive layers 20 configured to uniformly distribute heat over an exterior of subsea flowline 100; one or more insulating layers 30 adapted to shield subsea flowline 100, the predetermined set of heaters 10, and conductive layers 20 from ambient seawater temperature; an anchor; and a strength member. The predetermined set of heaters 10 may comprise one or more mineral insulated cables capable of reaching very high temperatures with very little power and minimal controls.

Abstract: Fluid charging system can provide a higher inlet pressure than the ambient pressure for pumps intended to operated and comprises one or more subsea fluid reservoirs; one or more charge pumps configured to provide an output pressure higher than ambient pressure; various fluid conduits in fluid communication with the subsea fluid reservoirs and charge pumps; and various valves. Fluid is provided to a bladder at a first fluid pressure and fluid charging system used to provide protection for the subsea fluid reservoir and inlet conditions of the subsea pump. A second valve is used to protect the subsea fluid reservoir from pressure leaking back and a feedback loop used to protect inlet conditions of the subsea pump by setting the feedback loop valve to open near the maximum inlet condition.

Abstract: Dynamic/static sealing of coiled tubing subsea for pipeline and well access with hydrostatic conditions up to 10,000 feet water depth while maintaining wellbore or pipeline pressures up to 10,000 psi may be achieved using a system comprising a subsea fluid source which utilizes a riserless open water coiled tubing system and an open water coiled tubing sealer to control hydrostatic pressure and wellbore/pipeline pressures.