CASING HEAD Russian patent published in 2009 - IPC E21B33/03 

FIELD: mining.

SUBSTANCE: invention refers to mining and can be implemented as control head at operation of oil and gas wells for sealing well head, for hanging stalk pipe string, for control over well operation mode, for shutting off and directing withdrawn production into manifold, and also for performing various process operations. The casing head consists of a cylinder case with upper and lower connecting flanges and with two upper and two lower side branches with connecting flanges for installation of gates, of a tube holder installed in the axial channel of the case, of an assembly for fastening and sealing tube holder in the axial channel of the case; also the casing head consists of a transition flange assembled on the cylinder case. Over the tube holder in the axial channel of the case there is installed a shutoff ball element with pass through axial and blind side channels, axes of which are mutually perpendicular, and also with upper and lower seats with packs located on spherical working surface of the seats. The unit of control over the shutoff ball element is made in form of a connected to it shaft, the axis of which is perpendicular to axes of pass through and blind side channels and passes through their cross point. Circular grooves are made on spherical working surfaces of the upper and lower seats; internal diametre of these grooves exceeds external diametre of seats packs made in form of gasket rings installed correspondingly above and below the said circular grooves. A groove is made on external cylinder surface of the upper seat; from one side this groove is connected with a channel for lubricant supply, made in the cylinder case of the tube head, while from the other side this groove is connected with the circular groove located on spherical surface of the seat by means of radial channels cut in the seat. The shutoff ball element has channels arranged along the axis of the pass through axial channel; also, when the shutoff ball element is open, holes of the said channels coincide with the circular grooves on working spherical surfaces of the seats, while one of these channels is connected with an additional channel made in the shutoff ball element. Its axis is perpendicular to the axis of the pass through axial channel. The shaft of the unit of control over the shutoff ball element is made in form of two coaxial shafts, ends of which have grooves; between ends of the shafts there is located a disk equipped with mutually perpendicular lugs made on its end surfaces for interacting with grooves of shafts. The said shafts and disks are made with axial grooves for communication with the additional channel of the shutoff ball element.

EFFECT: upgraded reliability of production tree.

2 dwg