Flow Diversion Valve for Downhole Tool Assembly

Abstract

A casing removal system includes a flow diversion valve. The flow diversion valve includes a flow switch that engages an upper end of an inner casing. When the flow switch engages the upper end of the inner casing, the flow diversion valve opens and at least a portion of the fluid flow through the casing removal system exhausts to the annulus. The remaining fluid flow below the flow diversion valve is insufficient to operate a mud motor that drives a casing cutter. In other embodiments, when the flow switch is not engaged with the inner wall of casing, the flow diversion valve prevents fluid flow to components that are downhole of the valve and when the flow switch is engaged with the inner wall of casing, the flow diversion valve allows for fluid flow to components that are downhole of the valve.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS[0001]This application claims the benefit of U.S. provisional patent application No. 62 / 891,451, filed Aug. 26, 2019, which is incorporated by reference for all purposes.BACKGROUND OF THE DISCLOSURE[0002]Well bores may be lined with one or more casings. Casings are installed to provide structure and geotechnical support for the wellbore, to facilitate fluid flow through the wellbore, and for many other reasons. Over the course of a wellbore's operational lifetime, and at the end of the wellbore's operational lifetime, it may be desirable to remove a casing. Casing removal involves gripping the casing with a spear and applying a removal force on the casing. If the removal force is insufficient to remove the casing, the casing may be cut to reduce the length of the casing to be removed, and therefore reduce the total strength of the connection holding the casing in the wellbore.SUMMARY[0003]In one representative embodiment, a flow diversion valve...

AI Technical Summary

Benefits of technology

[0003]In one representative embodiment, a flow diversion valve is comprised of housing with upper and lower ends configured for coupling to another downhole tool to form a downhole tool assembly. The housing having defined through it a flow path and actuatable valve interposed in the flow path to control fluid flow from the lower end of the housing. The flow diversion valve has least one moveable actuation member that extends beyond the outer diameter of the housing under the influence of a biasing force and is configured to be the moved at least partially inwardly with respect to the housing against the biasing force when the flow diversion valve passes from a first casing to a second casing that has an inner diameter smaller than the inner diameter of the first casing. Movement of the actuating member changes the rate of fluid flow existing the flow diversion valve.

Problems solved by technology

If the removal force is insufficient to remove the casing, the casing may be cut to reduce the length of the casing to be removed, and therefore reduce the total strength of the connection holding the casing in the wellbore.

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