A thermally-insulated subsea pipe, comprising a rigid inner flowline pipe 12; wet insulation 16 disposed around the flowline pipe; spaced-apart bridge structures 22 that extend radially from the flowline pipe toward the wet insulation to hold the wet insulation apart from the flowline pipe, thus defining an annular space 20 between the flowline pipe and the wet insulation; and dry insulation 24 disposed between the bridge structures in the annular space. Aspects include the bridge structures bonded to the wet insulation, for example by welding, and so may be of the same material as the wet insulation or a compatible material that permits welding. The wet insulation may be selected from, or comprise: syntactic foam; polyurethane; polypropylene; or other polymers. The dry insulation is selected from or comprises: a microporous material; an aerogel; Izoflex (RTM); Rockwool (RTM); or a polymer foam.
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