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

FIELD: mining.

SUBSTANCE: invention relates to equipment for sealing of mouth of inclined wells of superviscous oil (SVO) during their operation and repair in order to ensure safety, prevention and elimination of oil and gas manifestations (OGWI), including equipped with two-row string. Ram preventer comprises upper and lower flanges rigidly connected to the housing, the housing is equipped with a vertical circular axial channel, side horizontal channels are arranged symmetrically relative to the axial channel, in the first horizontal channels there installed are ram blocks, in which there are tube rams equipped with elastic seals, and manual control drives of rams, which include driving rods of rams, having threaded connections for interaction with covers screwed into the casing. Chamber cavities of ram blocks in cross section have rectangular shape, and elastic seals are arranged in slots made in tube rams. Upper and lower parts of the axial channel of the housing are equipped with conical mounting surfaces. Upper conical surface is made tapering from top to bottom, in it replaceable sealing bushing, made in form of two semi-rings equipped with external circular recesses. Bottom conical surface is tapered from bottom to top, in it replaceable centralizer, which inner diameter depends on diameter of pipe string, lowered into inclined well. In upper flange there are second horizontal channels of round shape in cross section, outer side thrusts are screwed into the horizontal channels of the upper flange in tight design and interact with sliding cylindrical slides arranged in the horizontal channel. Sliding sliders are equipped with key and shaped slots, and upper flange is equipped with keys, installed in key slots of sliding slides, with the possibility of radial movement within the key slots and fixation of sliders by shaped slots for external circular recesses of upper replaceable sealing bushing, preventing axial movement of replaceable sealing bushing upwards. Lower end of centralizer is located below lower end of lower flange. Elastomer seals of preventer are made of heat-resistant rubber. Lower flange is replaceable and equipped with two L-shaped grooves arranged symmetrically relative to each other, each L-shaped groove is made of interconnected vertical short and horizontal long sections. In lower part of external side of preventer is two guide pins with possibility of axial and radial movement of pins in corresponding L-shaped slots with subsequent fixation on end of horizontal long sections of L-shaped slots with locking screws.

EFFECT: ram preventer achieves operational reliability, safe operation at well head of inclined wells in case of OGWI occurrence, provides for high-quality sealing of pipe string, reduced duration of SVO well repair, tightness of ram preventer in case of steam emission at temperature up to plus 300 °C.

3 cl, 4 dwg