US 12,123,521 B2 · Subsea installations comprising corrosion-resistant flowlines

Abstract

A method of installing a subsea tie-in conduit comprises unspooling or manufacturing a steel rigid lined pipeline aboard an installation vessel and launching the pipeline progressively into water. A distal end of the tie-in conduit is coupled to a proximal end of the pipeline above the surface and is then launched into the water coupled to the pipeline. The suspended weight load of the pipeline is supported by an A&R wire connected to the proximal end of the pipeline, defining a load path that bypasses the tie-in conduit. A proximal end of the tie-in conduit may be suspended from that wire. The tie-in conduit is of composite or flexible pipe, hence being pliant relative to the lined rigid pipeline and maintaining its internal corrosion resistance. After landing on the seabed, the tie-in conduit may be deflected relative to the pipeline for connection to a subsea connection point.

Claims27

Dependent claims

A method of installing a subsea tie in conduit, the method comprising:

unspooling or manufacturing a rigid pipeline aboard an installation vessel;
launching the pipeline progressively from the vessel into water;
coupling a distal end of the tie in conduit to a proximal end of the pipeline aboard the vessel, the tie in conduit being pliant relative to the pipeline;
and
before landing the proximal end of the pipeline on the seabed, launching the tie in conduit fully into the water coupled to the pipeline, while supporting a suspended weight load of the pipeline along a load path that substantially bypasses the tie in conduit.

2 more elements

Dependencies are inferred from the claim text.

Subsea installations comprising corrosion-resistant flowlines

Life of this patent

Subsea installations comprising corrosion-resistant flowlines

Life of this patent

Abstract

Claims27