Method and apparatus for controlling well pressure while undergoing subsea wireline operations

摘要

The disclosure defined by this invention is a method and assembly for conducting wireline operations in a deep, subsea location, which includes providing a rig on the surface of a body of water, having a riser extending from the rig floor to the floor of the deep body of water; an annular preventer positioned on the end of the riser on the sea floor; a plurality of blowout preventers positioned below the riser to prevent a blowout into the riser; and, a wireline subsea blowout preventer control head assembly. A lubricator is lowered into the riser, with the control head assembly attached thereto, and wherein the wireline tool is disposed within the control head assembly. The lubricator is position within the annular preventer. Wireline operations may then be conducted. If a blowout occurs during wireline operations, any pressure would be prevented from entering the riser, and would be contained by the control head assembly. Thereafter, the assembly and lubricator is rigged down.