Improved Downhole Tool Liner

Abstract

A liner insertable into the central bore of a downhole tool includes a resilient material rolled into a substantially cylindrical shape. The outside diameter of the liner is variable to allow the liner to be inserted into a narrowed bore of the downhole tool near the box end or pin end. Once past the narrowed bore, the outside diameter of the liner self-expands within the central bore of the downhole tool. The outside diameter of the liner may expand to contact the inside surface of the central bore. In selected embodiments, a transmission line may be routed between the central bore and the outside diameter of the resilient material. The liner may be effective to protect the transmission line from materials traveling through the central bore.

Description

FEDERAL RESEARCH STATEMENT [0001] This invention was made with government support under Contract No. DE-FC26-97FT343656 awarded by the U.S. Department of Energy. The government has certain rights in the invention.BACKGROUND OF INVENTION [0002] 1. Field of the Invention [0003] This invention relates to oil and gas drilling, and more particularly to apparatus and methods for reliably transmitting information along downhole drilling strings. [0004] 2. Background of the Invention [0005] In the downhole drilling industry, MWD and LWD tools are used to take measurements and gather information with respect to downhole geological formations, status of downhole tools, conditions located downhole, and the like. Such data is useful to drill operators, geologists, engineers, and other personnel located at the surface. This data may be used to adjust drilling parameters, such as drilling direction, penetration speed, and the like, to accurately tap into an oil, gas, or other mineral bearing rese...

AI Technical Summary

Benefits of technology

[0015] In selected embodiments, the outside diameter of the resilient material expands to contact the inside surface of the central bore. In other embodiments, a transmission line is routed between the central bore and the outside diameter of the resilient material. The resilient material may keep the transmission line in contact with the inside surface of the central bore. The resilient material may also be effective to protect the transmission line from materials traveling through the central bore.

[0016] In certain embodiments, a channel is formed in the resilient material to accommodate the transmission line. In other embodiments, the resilient material includes two mating surfaces that come together to form the cylindrical shape. Movement between these mating surfaces is effective to cause a change in diameter of the resilient material. In selected embodiments, the mating surfaces are sealed together to prevent substances from leaking into or out of the liner. In certain embodiments, once the resilient material has expanded within the central portion of the downhole tool, the resilient material is maintained in place by shoulders in the central bore.

[0018] In selected embodiments, the method includes expanding, by the resilient material, the outside diameter of the resilient material to contact the inside surface of the central bore. In other embodiments, the method includes routing a transmission line between the central bore and the outside diameter of the resilient material. The resilient material may maintain contact between the transmission line and the inside surface of the central bore. The resilient material may also protect the transmission line from materials traveling through the central bore.

[0019] In selected embodiments, the method may include forming a channel in the resilient material to accommodate the transmission line. In other embodiments, the resilient material includes two mating surfaces that mate together to form the cylindrical shape. The diameter of the resilient material may be varied by moving the mating surfaces with respect to one another. In selected embodiments, the method may further include sealing the mating surfaces to one another to prevent substances from leaking into or out of the liner.

Problems solved by technology

Nevertheless, data gathering and analysis represent only certain aspects of the overall process.

However, most traditional methods are limited to very slow data rates and are inadequate for transmitting large quantities of data at high speeds.

Nevertheless, many of these efforts have been largely abandoned or frustrated due to unreliability and complexity.

For example, one challenge is effectively integrating a transmission line into a downhole tool, such as a section of drill pipe.

In some cases, milling or forming a channel in the wall of the downhole tool to accommodate the transmission line may excessively weaken the wall.

Nevertheless, routing the transmission line through the central bore may expose the transmission line to drilling fluids, cements, wireline tools, or other substances or objects passing through the central bore.

This can damage the transmission line or cause the transmission line to interfere with objects or substances passing through the central bore.

Moreover, in directional drilling applications, downhole tools may bend slightly as a drill string deviates from a straight path.

This may cause the transmission line to deviate away from the inside surface of the central bore, thereby worsening the obstruction within the central bore.

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