Abstract: A subsea subterranean well completion has a tubing string with a portion that extends through a region of the completion exposed to temperatures sufficiently low to potentially create wax and/or hydrate deposits within the tubing string during pre-production or shut-down periods. In order to inhibit or remove the formation of these deposits, the well completion is provided with a flow assurance system operative to create a flow of heating fluid which is recirculated through the space between the tubing string portion and the well casing/production riser structure in a manner causing the heating fluid to flow along the outer side of the tubing string portion without previously or subsequently traversing the interior of the tubing string. The heat absorbed by the tubing string inhibits or removes wax and/or hydrate formation in production fluid therein without the previous necessity of using a chemical injection system to inject plug-inhibiting chemicals into the interior of the tubing string.

Abstract: A method and associated apparatus provide enhanced safety in subterranean well completions while permitting other production issues to be addressed efficiently and cost effectively. In a preferred embodiment, a method of producing a subterranean well utilizes an isolation packer having an inner mandrel through which fluid transmission lines and electrical transmission lines may be conveniently installed. A unique configuration of the packer permits a surface controlled subsurface safety valve, fluid property sensors, injection subs, etc., to be installed below the packer with the various lines used therewith extended axially through the mandrel.