Intermediate support device for ultra-deep drilling borehole

Abstract

The invention discloses an intermediate support device for ultra-deep drilling borehole, comprising a pre-buried barrel buried in the wall of the borehole; the pre-buried barrel is disposed along the radial direction of the borehole, and both ends thereof are connected with the inside and outside of the borehole wall; one end of the pre-buried barrel towards the inner cavity of the borehole is provided with a connecting flange; the connecting flange is connected with an oil cylinder support; a hydraulic cylinder is disposed on the oil cylinder support; a barrel-shaped piston shoe is coaxiallydisposed in the pre-buried barrel; an O-shaped sealing ring is disposed between the outer circumference of the piston shoe and the inner wall of the borehole; and the outer end of the piston shoe is provided with a plugging flange. The invention solves the instability problem of the borehole, which makes it possible that the drilling construction method can be used in deep well more than 700 meters after solving the instability problem; and through adding the layers of the intermediate supports, the vertical stability problem of drilling 1000-meter deep well is solved.

Description

Technical field: [0001] The invention relates to an intermediate support device for an ultra-deep drilling shaft. Background technique: [0002] If the vertical instability of the wellbore in ultra-deep drilling (above 700 meters) occurs, there will be two consequences. One is that the wellbore wall will be close to the side of the drilling well after the wellbore becomes unstable, causing the deformation of the wellbore structure, which will cause the destruction of the wellbore and the mud outside the wellbore. The wellbore is filled with water from the formation and the formation, causing the wellbore to collapse, resulting in catastrophic consequences; another situation is that the wellbore is dumped on the side of the well without causing damage to the wellbore. The effective circle diameter of the shaft is greatly reduced, the hoisting sectional area of ​​the wellbore cannot meet the design requirements, the wellbore cannot meet the use requirements, and the wellbore b...

AI Technical Summary

Problems solved by technology

[0004] Usually, the method to solve the vertical instability is to increase the principal moment of inertia of the cross-section centroid of the wellbore structure to achieve the purpose of enhancing the vertical stiffness of the wellbore. , the drilling diameter becomes correspondingly larger, which increases the cost of the entire wellbore

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