Dual barrier open water completion

摘要

A method of completing a subsea borehole including connecting a first vessel to a subsea wellhead assembly via a riser. A borehole is drilled with a drill string communicated to the subsea wellhead assembly through the riser. A lower completion assembly is run on a service string into the borehole through the riser. At least two barrier valves of the lower completion assembly are set with the service string in order to form a mechanical barrier to fluid flow with each of the at least two barrier valves. The riser is disconnected from the subsea wellhead assembly. An upper completion string is run through open water to the borehole and connected to the lower completion assembly. An lower completion assembly for a subsea borehole is also included.

主权项

1. A method of completing a subsea borehole comprising:
connecting a first vessel to a subsea wellhead assembly via a riser; drilling a borehole with a drill string communicated to the subsea wellhead assembly through the riser; running a lower completion assembly on a service string into the borehole through the riser, the lower completion assembly including a tubular string having an uphole end portion spaced from the wellhead assembly and, at least two barrier valves arranged within the tubular string; setting the at least two barrier valves arranged within the tubular string of the lower completion assembly with the service string prior to running an upper completion string in order to form a mechanical barrier to fluid flow with each of the at least two barrier valves; disconnecting the riser from the subsea wellhead assembly; running the upper completion string through open water to the borehole; and connecting the upper completion string to the lower completion assembly.