FIELD: oil and gas industry.
SUBSTANCE: invention relates to a device for sealing the mouth of oil and gas wells with an inclined mouth and a two-row pipe string. The proposed device for sealing the running of a two-row pipe string into an inclined well contains a preventer (1) with lifting lugs (2 ', 2' ') and a cast bottom flange (3), and equipped with a replaceable ring (5). In this case, the replaceable ring is installed under the lower flange with the possibility of hermetically sealed fastening with a bolted connection (7). The bottom flange (3) of the BOP (1) is equipped with a metal ring (6), which is sealed to the support flange (8) of the wellhead assembly. The replaceable ring (5) is made with annular grooves with the possibility of installing sealing metal rings (9). The device is also equipped with a pipe hanger for the first row of the pipe string, and the lower flange of the pipe hanger is attached from below to the support flange of the wellhead. At the same time, threaded holes are diametrically made in the pipe holder from above with a connecting and sealing size corresponding to the connecting and sealing size of the bottom flange of the preventer. In addition, the device is equipped with centralizers (16', 16''), installed in the device before attaching the preventer to the support flange (8) of the wellhead assembly or pipe hanger. The inner diameters of the centralizers depend on the diameters of the double-row pipe string, which is lowered into the deviated well, and the lower and upper ends of the centralizers are equipped with chamfers. The inner surfaces of the metal O-rings are fitted with 5mm high temperature FRM O-rings. Additionally, the device is equipped with two slings of different lengths for mounting the preventer on the support flange of the wellhead and the pipe hanger. In this case, the difference between the length of the lines depends on the distance between the lifting lugs of the preventer. To seal the internal space of the first and / or second row of pipe strings, a shut-off element is used.
EFFECT: increases reliability and expanding technological capabilities of the device when carrying out sequential trips with two pipe strings in an inclined well with ability to adjust the angle of inclination of the preventer when installing it on the support flange of the wellhead in an inclined well.
1 cl, 4 dwg
