Dry tree subsea well communications methods using variable tension large offset risers

摘要

Disclosed are methods to counter buoyancy and install variable tension risers using a weighted chain ballast line. An example of an apparatus used in conjunction with the embodiments includes compliant variable tension risers to connect deep-water subsea wellheads to a single floating platform. The variable tension risers allow several subsea wellheads, in water depths from 4,000 to 10,000 feet, at lateral offsets from one-tenth to one-half of the depth, to tie back to a single floating dry tree semi-submersible platform.