Shock-resisting downhole screw type pulse generator

Abstract

The invention provides a shock-resisting downhole screw type pulse generator which comprises an outer shell, a lock nut, a gland nut, an upper thrust bearing, a lower thrust bearing, a flexible rod, a stator rubber tube, a hollow rotor, a movable valve disk and a fixed valve disk. The flexible rod is arranged on the inner side of the outer shell and comprises a disk-shaped structure; a plurality of tap holes are formed in the disk-shaped structure; the lower thrust bearing is arranged below the disk-shaped structure; the upper thrust bearing is arranged on the disk-shaped structure; the gland nut is arranged on the upper thrust bearing; the lock nut is arranged on the gland nut; the hollow rotor is arranged on the inner side of the stator rubber tube; the lower end of the flexible rod is fixed to the hollow rotor; and the movable valve disk is located below the hollow rotor. The interval between the movable valve disk and the fixed valve disk of the shock-resisting downhole screw type pulse generator can be adjusted, and installation and adjustment of the whole machine are facilitated.

Description

technical field [0001] The invention belongs to the technical field of petroleum, in particular to an anti-shock downhole screw pulse generator. Background technique [0002] During the directional drilling process of oil drilling, the downhole motor provides the rotary power for the drill bit, and the drill string is stationary relative to the well wall. The contact pressure of the drill string to the well wall increases the axial frictional resistance and the rotational torque of the drill string. When the friction of the drill string accumulates to a certain value, the gravity (weight on bit) of the downhole drilling tool assembly cannot be effectively transmitted to the drill bit, and normal drilling cannot be performed. At the same time, the strength of the drill string may be damaged, resulting in downhole accidents. [0003] During drilling, the pressure fluctuation inside the drill string can provide vibration for the drill string, so that the static friction betwee...

AI Technical Summary

Problems solved by technology

However, due to the direct frictional contact between the fixed valve disc and the movable valve disc in the conventional screw-type pulse generator, the valve disc is usually made of high hardness and brittle materials such as cemented carbide or ceramics, which has the following disadvantages: 1. The rotor Lack of radial mechanical limitation, while rotating in the stator housing, it rotates along the central axis, which drives the uneven radial contact impact between the valve discs and shortens the service life

2. The rotor lacks axial mechanical restrictions, and will generate periodic vibration along the axis under the action of periodic pressure changes, thereby driving uneven radial impact between the valve discs and shortening the service life

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