PREVENTER FOR WELLS WITH INCLINED MOUTH Russian patent published in 2020 - IPC E21B33/06 

FIELD: oil and gas industry.

SUBSTANCE: invention relates to sealing equipment for wellheads of oil and gas wells during their operation and repair in order to ensure safety, prevention and elimination of oil, gas and water ingresses (OGWI) at wells with inclined wellhead. Preventer comprises upper and lower flanges rigidly connected to housing, housing is equipped with vertical circular axial channel, relative to axial channel there are symmetrically arranged side horizontal channels, longitudinal axis of the side horizontal channels are located perpendicular to the axis of the vertical channel, in the first horizontal channels made in the housing with the possibility of longitudinal movement, there are installed ram blocks, in which there are pipe dies equipped with elastic seals, and manual control drives of dies, which include driving rods of dies, having threaded connections for interaction with covers screwed into housing. Chamber cavities of ram blocks in cross section have rectangular shape, and elastic seals are arranged in slots made in tube plates. Upper and lower parts of the axial channel of the housing are equipped with conical mounting surfaces. Upper conical surface is tapering from top to bottom, and there is an upper detachable centering sleeve made in the form of two semi-rings equipped with external annular recesses, and the lower conical surface is tapered from bottom to top and a lower replaceable centralizer is installed in it. In upper flange there are second horizontal channels of round shape in cross section, lateral helical thrusts are screwed out from the outside into horizontal channels of upper flange in tight design interacting with sliding sliders of cylindrical shape arranged in horizontal channel. Retractable slides are equipped with key and shaped slots, and upper flange is equipped with keys, installed in key slots of sliding slides, having the possibility of radial movement within key slots and fixation of sliders by shaped slots as outer annular recesses of upper replaceable centering sleeve from axial movement upwards. Angles of inclination of conical mounting surfaces provide distance between lower end of upper replaceable centering bushing and upper end of lower replaceable centralizer, smaller than length of sleeve of sealed pipe string with minimum diameter. Elastic baffles of preventer are made of heat-resistant rubber, and upper replaceable centering bushing and lower replaceable centralizer are made of babbite alloy.

EFFECT: technical result consists in improvement of reliability of work, quality of sealing of pipe string, safety of work in case of OGWI at the head of inclined wells of ultraviscous oil, reducing duration of well repair and providing tightness of preventer in case of steam release.

1 cl, 3 dwg