PACKING ELEMENT OF WELLHEAD Russian patent published in 2010 - IPC E21B33/06 

FIELD: gas-and-oil industry.

SUBSTANCE: invention refers to cylinder case with central through channel wherein there are installed packing element out of elastic material and hydraulic compensator. The packing element is composed with two circular cylinder components - an external and replaceable internal one arranged coaxially. Also the replaceable component interacts with a centraliser and a cover pressure tight closing the cavity of the case. The hydraulic compensator consists of a working chamber in form of a circular cavity positioned outside the packing element and filled with working fluid; the cavity is communicated with an external source of hydraulic feed via the channel; further, the compensator consists of a cavity hydraulically connected with the wellhead and of a divider between the working chamber and this cavity. The divider corresponds to a cylinder shell out of elastic material with restricting rings out of rigid material outside. Pressure in the working chamber can be controlled due to improved system of hydraulic channels facilitating continuous pressure tightness at the wellhead; the divider compensates excessive loads on internal packing component through which a coupling passes.

EFFECT: increased reliable pressure tightness and wear resistance of disclosed facility.

3 dwg