FIELD: oil and gas.
SUBSTANCE: invention relates to a plug for long-term preservation of the wellhead tree of an underwater oil and gas well. The plug includes the upper bushing. It also includes a plug, with at least one lifting device attached to it, installed in the upper bushing. It includes a hydraulic control unit mounted on the upper bushing and connected to the internal cavity of the plug by pipelines. It also includes a bottom bushing. Also, it includes at least one piston having a protrusion, at the end of which there is a recess with the ability to supply liquid into it upon command from the hydraulic control unit, and at least one segment. The upper bushing and the lower bushing are designed in such a way that when the upper bushing is connected to the lower bushing, a cavity is formed between them, in which at least one piston is placed with the possibility of axial movement, having a surface interacting with at least one segment installed in a groove in the bushing bottom with the possibility of predominantly radial movement. The other end of the segment has a profile that interacts with a counter profile on the well head. The piston moves due to the supply of fluid into the cavity formed by the upper and lower bushings, upon command from the hydraulic control unit.
EFFECT: reliable fixation of the plug on the wellhead tree of an underwater oil and gas well, as well as the use of the plug when carrying out work using a robotic method.
4 cl, 6 dwg
