DEVICE FOR RESTORATION OF DEFECTIVE SECTIONS OF PRODUCTION STRINGS OF OIL AND GAS WELLS WITH CONTROLLED CONE-TRANSFORMER

摘要

FIELD: oil and gas industry.;SUBSTANCE: device comprises a plaster in the form of a smooth metal branch pipe with elastic sealing rings outside, and an expanding mandrel made in the form of cone-transformer formed by cone-shaped sectors located in the grooves of the body conical part configured for longitudinal movement. The vertex of the cone-transformer body is directed to the side opposite to the working stroke of the expanding mandrel which provides the smoothest expansion of the plaster. The device is provided with a counter-return device for preventing backward stroke. A block of power reinforced collars is used as a piston driving the cone-shaped sectors. To control geometry of the cone-transformer, the latter is equipped with a deblocking mechanism.;EFFECT: emergency situations are prevented when eliminating a leakage from production strings in case of expanding mandrel jamming, reliability and efficiency of device operation is increased.;3 cl, 10 dwg