DOWNHOLE PIPE DISCONNECTOR Russian patent published in 2024 - IPC E21B17/06 E21B33/14 

FIELD: oil and gas industry.

SUBSTANCE: invention relates to oil and gas industry and can be used for disconnection of bearing string of drill pipes with suspended liner or section of well casing during their lowering and cementing. Disconnector comprises a housing in the form of a pipe with an axial hole and an external stepped surface, the upper stage of which is connected through a sub to the bearing string of drill pipes. Power casing is installed on the housing with the possibility of longitudinal movement and rotation to the right, clockwise, connected to it by shear pins. In the cavity of the power casing there is a collet with elastically deformable blades, on the lower part of which there is a left cylindrical thread interacting with the thread of the funnel coupling. Rod made in the form of a pipe with an axial hole and an external stepped surface is rigidly connected to the lower part of the housing, the lower stage of which interacts with the cylindrical bore of the funnel coupling. On the outer surface of the rod there is a shaped annular groove to accommodate the threaded part of the elastically deformable collet blades after their disconnection from the thread of the funnel coupling. In the cavity of the power casing there is a differential bushing with the possibility of longitudinal movement upwards along the outer surface of the stock, it is connected to the stock by shear pins and forms an annular cavity with its upper step, which is hydraulically connected by a radial hole to the axial hole of the stock. Bushing fixes the left cylindrical thread of the elastically deformable collet blades in the state of interaction with the thread of the funnel coupling. Upper elements of torque transfer to the right, clockwise, from the lower stage of the housing to the power casing and the collet are made in the form of a splined connection with the number of N₁ protrusions and mating grooves of at least three, which are evenly located along the circumference. Lower elements of torque transfer to the right, clockwise, from the power casing to the funnel coupling are made in the form of a tongue-and-groove connection with the number of N₂ studs and mating grooves at least two, which are evenly located along the circumference. Additionally, it contains the unit of mechanical method of disconnection of the left cylindrical threads of the funnel coupling and the elastically deformable collet blades, which comprises a nut connected with power casing to make annular cavity with housing upper stage to accommodate compression spring.

EFFECT: higher reliability.

1 cl, 7 dwg