WELLHEAD PACKER Russian patent published in 2024 - IPC E21B33/12 

FIELD: oil industry.

SUBSTANCE: invention relates to the oil industry and is intended for temporary shutting off of a well shaft during insulation works during operation and overhaul of wells, and survey of formations. Wellhead packer includes a hollow shaft with a sealing element outside, a lower support, a lower sub with a lower radial hole below the sealing element, structural elements covering the holes and made with possibility of destruction at a certain excess pressure inside the hollow shaft. Sealing element is made in the form of a self-sealing collar, which does not pass from top to bottom, above which there is an upper sub with an upper radial hole. Upper and lower holes are closed by upper and lower structural elements, respectively, lower of which is made with possibility of destruction by excess pressure, which is 10-15 % more than for upper one, which are used to equalize pressure in order to exclude spillage and for transfer to transport position of sealing collars by means of pumping to below-packer area. Below the lower sub inside the hollow shaft there is a valve seat for a ball dropped from the wellhead, and the lower support is made in the form of a streamlined nozzle located from below on the extension and made with possibility of interaction with the well bottom, and unit of centralisers, made with possibility of interaction with upper end of narrowing of wellbore in case of its presence and exclusion of excessive axial displacement of packer at pressure drop, by means of resting on beginning of filtering part of string, which diameter is less than production string.

EFFECT: simplification of design and increase of its reliability due to exclusion of movable precisely adjusted parts.

1 cl, 5 dwg