COMBINED PREVENTOR FOR REPAIR WORKS IN OIL AND GAS WELLS USING COIL TUBING

摘要

The proposed utility model relates to the oil and gas industry and is designed to seal the wellhead of oil and gas wells in order to prevent gas and oil water seepage during repair work using coiled tubing (or otherwise a continuous pipe installation, or otherwise a flexible pipe). The objective of the proposed technical solution is to improve the reliability of prevention the occurrence of gas and oil water showings (open flowing) during repair work in wells using coiled tubing (coiled tubing), as well as sealing the wellhead in the area of the preventer when the tool is pulled to the surface. The technical result consists in the development of a reliable combined preventer that allows it to work as standard wedge and shear / blind dies due to the working fluid supplied to the channels for closing the dies, as well as overlapping the internal channel of the blowout preventer when removing the tool used in the repair of wells dinners, to the surface. In other words, the design of the preventer provides an additional "barrier" to prevent the occurrence of open flowing of the well in the absence of coiled tubing in the area of action of the preventer ram. The set task and technical result are achieved by the fact that the reverse a valve, the closing mechanism of which is a flap (or otherwise a flap check valve). Before running the tool into the well, the valve leaf is in a closed position, which reduces the risk of open flowing of the well when installing the tool in the lubricator (since in this case, the closed buffer valve of the Christmas tree, as well as the closed valve of the valve type of combined preventer). When running the tool into the well, the check valve closing mechanism is in the open position due to the supply of low-viscosity oil hydraulic pressure. In this case, the prevention of open flowing of the well is carried out by the sealing device located under the injector, as well as by closing the pipe / wedge rams. In the event of complications that can lead to open flowing of the well, prevention is carried out by closing the shear / blind dies. After carrying out repair work and lifting the tool on a coiled tubing to the surface, and when it passes through the check valve, the valve mechanism closes due to the release of the hydraulic pressure of the oil (in this case, the buffer valve of the Christmas tree, which is closed immediately after extraction tool, as well as the closed valve of the wing-type combination BOP).