BOP FOR A WELL WITH A DOUBLE-ROW PIPE STRING Russian patent published in 2023 - IPC E21B33/06 

FIELD: oil and gas industry.

SUBSTANCE: equipment for sealing the mouth of oil and gas wells, in particular preventers for a well with a double-row pipe string, during their operation and repair (in the absence of both pipe strings in the well) in order to ensure safety, prevention and elimination of oil and gas water vapor ingress (OGWVI), protection of subsoil and environment. A BOP for a well with a double-row pipe string contains upper and lower flanges rigidly connected to a housing equipped with a vertical round axial channel. In the housing, relative to the axial channel, the upper and lower rows of lateral horizontal channels are symmetrically located, in each of which, with the possibility of longitudinal movement, ram blocks are installed, in which pipe rams are located, equipped with elastic seals, and manual ram control drives, including ram drive rods. Pipe rams with elastic seals are placed in the ram blocks of the upper side horizontal channels to seal a pipe string with a smaller outer diameter. Pipe rams with elastic seals are placed in the ram blocks of the lower side horizontal channels to seal a pipe string with a larger outer diameter. The BOP is fixed on the wellhead flange and is configured to be placed below the preventer in the wellhead flange of the pipe holder, equipped with two eccentrically located vertical holes of larger and smaller diameters, providing fastening of the upper ends of pipe strings lowered into the well with larger and smaller outer diameters. The BOP is equipped with shut-off valves, which consist of two pipes: a larger and a smaller diameter, hydraulically connected to each other by a hollow sleeve, plugged on both sides. The smaller diameter pipe is equipped with a centralizer at the bottom and a ball valve at the top. The larger and smaller diameter pipes are equal to the corresponding diameters of the pipe columns of larger and smaller outer diameters lowered into the well. A larger diameter pipe is sealed with ram blocks of the lower row, and a smaller diameter pipe is sealed with ram blocks of the upper row. The height between the upper and lower ram blocks is no more than 1.1 times greater than the outer diameter of the hollow sleeve. At the upper ends of the upper pipe rams there are semi-circular recesses in which the centralizer of the branch pipe of a smaller diameter shut-off valve is installed.

EFFECT: expansion of the technical capabilities of a blowout preventer (BOP) for a well with a double-row pipe string in the absence of both pipe strings in the well, as well as a reduction in the duration of sealing of the wellhead and guaranteed safety of work at the wellhead for maintenance personnel in the event of an OGWVI.

1 cl, 6 dwg