Submarine device

摘要

The invention discloses a subsea device comprising a can, a string of risers, a blowout preventer and a string of tie-back pipes. The blowout preventer is installed on the can. The top of risers is connected to a rig and its bottom is mounted on the blowout preventer. The upper of tie-back pipes is fixed to the can. The lower of tie-back pipes is mounted to a wellhead in the seabed by a subsea wellhead apparatus and connected to the casings for collecting oil/gas stored in formations by the subsea wellhead apparatus. A passage communicating the blowout preventer with tie-back pipe is jointed on the can. A pipeline, transporting oil/gas, mud and cuttings in drilling process, is divided into two sections, both tie-back pipes and casings, by the wellhead apparatus settled on seabed, thereby ensuring security of the rig in the drilling process and stronger operability of entire production system.

主权项

1. A subsea device used for semi-submersible rig, comprising a buoyancy force adjustable can, a string of risers, a blowout preventer, a string of tie-back pipes, an inject valve fixed on the top of the can, a vent valve fixed on a side of the can, and a buoyancy force adjustment device connected to the inject valve;
the blowout preventer being directly installed on the top of the can, the top of the string of risers being connected to the rig and the bottom of the string of risers being mounted on the blowout preventer; the top of the string of tie-back pipes being fixed to the bottom of the can, the lower end of the string of tie-back pipes being mounted to a wellhead on the seabed through a subsea wellhead apparatus fixed on the seabed and being connected to a formation casing for collecting oil or natural gas stored in formations; and a passage being located in the can to communicate with the blowout preventer and the string of tie-back pipes; wherein the buoyancy force of the can is adjusted with the buoyancy force adjustment device, the inject valve and the vent valve to bear most of the weight of the string of tie-back pipes.