Expandable Reamer Blades Hydraulic Actuation

Solution Overview

Problem

Conventional methods for enlarging subterranean well bores, such as bi-center and eccentric bits, are limited by non-adjustable pass-through diameters and prone to wobbling, while expandable reamers can be damaged when passing through smaller diameters and face difficulties in removal.

Innovation Solution

An expandable reamer tool with blades that move from a retracted to an expanded position in an acute angle, actuated by hydraulic pressure, featuring a moveable inner sleeve and a seal to facilitate blade extension and retraction, allowing for adjustable clearance and improved stability.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Shape

If conventional bits (bi-center or eccentric) are used to enlarge borehole diameter, then the borehole diameter is increased, but the pass-through diameter is non-adjustable and the tool is prone to wobbling

Engineering Contradiction:

Improveborehole diameterVSAvoidpass-through diameter adjustability

Core Design Contradiction:

ShapeVSAdaptability or versatility

Solution Approach 1:

The reamer tool employs expandable blades that can dynamically change from a retracted state (for passing through smaller diameters) to an expanded state (for enlarging boreholes). This dynamic configuration allows the tool to adapt to different borehole sizes and conditions, resolving the contradiction between achieving enlarged diameter and maintaining pass-through flexibility.

Inventive Principle:

Principle #15Dynamics

2Adaptability or versatility

If expandable reamers are used to enlarge boreholes, then adjustable diameter is achieved, but the blades may be damaged when passing through smaller diameters

Engineering Contradiction:

Improvediameter adjustabilityVSAvoidblade durability

Core Design Contradiction:

Adaptability or versatilityVSReliability

Solution Approach 1:

The reamer tool is designed with blades in a retracted position by default, creating a protective configuration before entering the borehole. The blades only expand when hydraulic pressure is applied after the tool has successfully passed through the smaller diameter section, preventing damage during the transition phase.

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The retracted blade configuration acts as a protective cushion, shielding the cutting elements from damage during initial insertion through smaller diameters. The hydraulic actuation mechanism provides a controlled expansion process that prevents sudden stress on the blades.

Inventive Principle:

Principle #11Beforehand cushioning (Prior cushioning)

3Ease of manufacture

If expandable reamers with fixed clearance are used, then manufacturing is simplified, but removal from the borehole is difficult due to binding

Engineering Contradiction:

Improveclearance fixationVSAvoidtool removal

Core Design Contradiction:

Ease of manufactureVSEase of operation

Solution Approach 1:

The reamer tool employs expandable blades that can dynamically change from a retracted state (for passing through smaller diameters) to an expanded state (for enlarging boreholes). This dynamic configuration allows the tool to adapt to different borehole sizes and conditions, resolving the contradiction between achieving enlarged diameter and maintaining pass-through flexibility.

Inventive Principle:

Principle #15Dynamics

4Productivity

If blades are kept in an expanded position, then borehole enlargement is continuous, but the tool cannot pass through smaller diameter sections

Engineering Contradiction:

Improvereaming efficiencyVSAvoidborehole size compatibility

Core Design Contradiction:

ProductivityVSAdaptability or versatility

Solution Approach 1:

The reamer tool employs expandable blades that can dynamically change from a retracted state (for passing through smaller diameters) to an expanded state (for enlarging boreholes). This dynamic configuration allows the tool to adapt to different borehole sizes and conditions, resolving the contradiction between achieving enlarged diameter and maintaining pass-through flexibility.

Inventive Principle:

Principle #15Dynamics

Applied Scientific Principles

This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.

Function Achieved in This Case

Enables efficient enlargement of well bores with adjustable diameter and reduced risk of damage, facilitating easier removal by allowing blades to retract without binding, thus enhancing operational efficiency and safety.

Implementation Method 1

The blades may be moved from a first radially inward or retracted position to a second radially outward or expanded position by hydraulic pressure within the fluid passageway

Methodology Applied

Scientific EffectHydraulic pressure: Pressure Increase

Data Source

PatentUS9187960B2Expandable reamer tools

Publication Date: 2015.11.17 BAKER HUGHES CO

AI summary

Expandable reamer tools include an outer body, a fluid passageway extending through the outer body, and at least one blade configured to slide relative to the outer body between a retracted position and an expanded position. In some embodiments, the tools may include a formation-engaging surface comprising a gage area. In other embodiments, the tools may include a radially recessed area extending from a back edge of the formation-engaging surface. Methods for removing such expandable reamer tools from a borehole are also disclosed.