Slip stop friction sub

Abstract

A device, system, and / or method for hanging a casing in a borehole operation are provided. A gripping feature may be included on an inner surface of a larger casing. Then, a smaller casing is positioned within the larger casing, and the outer diameter of the smaller casing or the hanging mechanism is expanded to contact the larger casing's gripping feature. The result is a secure engagement between the two casings. This gripping feature may comprise grooves cut into the inner surface of the larger casing wherein the grooves may have a groove density, an uphole groove angle, a downhole groove, an orientation, and other features that improve the engagement between the two casings.

Description

FIELD OF THE INVENTION[0001]The invention relates to borehole casings and liners, and the invention specifically relates to liners that are securely hung from other casings or liners.BACKGROUND OF THE INVENTION[0002]A casing is a pipe that is inserted into a borehole and is typically cemented in place. Casings often extend all the way back to the wellhead and may have various diameters and lengths for a variety of reasons. Casings maintain the stability of the borehole and provide a controlled space for production equipment to operate, for example, to extract natural resources from the earth. Casings also protect the environment from the production equipment and related byproduct inside of the casings. In one example, environmental regulations mandate the preservation of fresh water zones, and casings protect the fresh water zones from production materials. Casings also provide a location to install a blowout preventer, which is a large valve that serves as a fail-safe against catas...

AI Technical Summary

Benefits of technology

The invention provides a device, system, and method for hanging a casing in a drilling operation that ensures a secure engagement between the casing and another casing or liner, preventing movement. This is achieved through the use of gripping features, such as grooves, on the inner surface of the other casing or liner that securely fit into the outer surface of the smaller casing. This friction fit creates a secure engagement that cannot be easily moved or separated.

Problems solved by technology

However, the setting sequence may also introduce some problems.

The sub-optimal engagement and resulting consequences may place unforeseen stress on equipment that results in damaged assets, a loss of well control, a redesign of the drilling operation and well, a completion / workover, an intervention, or a modification of directional or bottom hole locations.

However, the complex nature of these devices adds cost, and the device relies on moving spring-biased gripping features, which increase the chances of failure.

However, again, if the moving parts of this type of liner hanging mechanism fail, then the liner will fall down the bore hole.

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