IMPROVED WELL SEALING Russian patent published in 2023 - IPC E21B33/04 

FIELD: well.

SUBSTANCE: means for sealing the annular space in a well. In particular, a well is claimed comprising an inner casing pipe (14), an outer casing pipe (16), a clamping device (22) and a seal (10) for sealing the annular space in the well formed between the outer surface of the inner casing (14) and the outer casing (16). In this case, the inner casing pipe (14) contains: a central longitudinal axis passing along the longitudinal axis of the inner casing pipe (14), and an outer clamping surface (15), which is configured to be secured and clamped in the outer casing pipe (16). Moreover, the clamping device (22) contains: a pressure sleeve (20); and pressure ring (18). The pressure ring (18) and the pressure sleeve (20) have axially opposite conical annular surfaces such that the relative axial movement between the pressure sleeve (20) and the pressure ring (18) towards each other results in a decrease in the inner diameter of the pressure sleeve (20) to deform the wall of the outer casing pipe (16) inward to create a clamping force that grips the inner casing pipe (14) of the well. The seal (10) contains: a flexible metal sealing edge (12) protruding radially in the outer direction in the direction from the central longitudinal axis of the inner casing pipe (14), from the supporting surface of the inner casing pipe. In this case, the supporting surface has a reduced diameter in relation to the diameter of the pressing surface of the inner casing pipe, the metal sealing edge (12) has a peripheral sealing surface for sealing in relation to the inner surface of the outer casing pipe (16). The pressure ring (18) is configured to create a radial force sufficient to deform the pressure sleeve (20) and the outer casing pipe (16) inward to bend the sealing edge (12). In this case, the sealing edge (12) protrudes towards the annular space being sealed, and the angle (θ) of the protrusion is formed between the pressure surface (27) of the sealing edge (12) and the supporting surface (29) of the inner casing pipe (14). Angle (θ) of the protrusion of the sealing edge (12) is configured to decrease when the sealing edge (12) is bent inward under the action of the clamping force, and increase to the side when the sealing edge (12) is actuated by the pressure in the annular space acting on the pressurized surface (27), which is distributed in such a way as to press the sealing surface (26) against the inner surface of the outer casing pipe (16).

EFFECT: technical result is to increase the reliability of sealing the annular space at high pressure in the well.

15 cl, 5 dwg