Consumable Downhole Tool Removal via Thermal Combustion

Solution Overview

Problem

Conventional methods for removing disposable downhole tools from well bores are time-consuming and expensive, often requiring milling or drilling, and alternative methods like using explosives can yield inconsistent results, necessitating a reliable and efficient method for tool removal without mechanical intervention.

Innovation Solution

A consumable downhole tool made of materials that burn away when exposed to heat and oxygen, such as magnesium, combined with a torch using a flammable non-explosive fuel like thermite to create molten plasma, which compromises the structural integrity of the tool, allowing it to fall away without the need for milling or drilling.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If conventional milling or drilling methods are used to remove disposable downhole tools, then the tools can be removed from the well bore, but the operation becomes time-consuming and expensive

Engineering Contradiction:

Core Design Contradiction:

ReliabilityVSLoss of time

Solution Approach 1:

The patent replaces mechanical removal methods (milling or drilling) with a chemical/thermal system. A torch assembly generates intense heat that consumes the downhole tool through combustion, converting the mechanical removal process into a thermal-chemical process. This substitution eliminates the need for complex mechanical retrieval operations while achieving reliable tool removal.

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

Solution Approach 2:

The patent changes the physical state and chemical properties of the downhole tool by exposing it to extreme temperatures. The tool material undergoes phase changes and chemical reactions (combustion) when exposed to the torch, transforming from a solid structural material into consumed ash and gases. This parameter change enables the tool to be eliminated without mechanical intervention.

Inventive Principle:

Principle #35Parameter changes

2Productivity

If explosives are used to fragment the downhole tool, then removal time is reduced, but the results are inconsistent

Engineering Contradiction:

Core Design Contradiction:

ProductivityVSReliability

Solution Approach 1:

The patent replaces the explosive mechanical fragmentation method with a controlled thermal-chemical combustion process. Instead of using high-speed shock waves from explosives, the torch assembly provides sustained thermal energy that systematically consumes the tool material through oxidation reactions, producing more consistent and predictable results.

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

Solution Approach 2:

The patent converts the potentially harmful uncontrolled explosive fragmentation into a beneficial controlled combustion process. By using the torch to generate controlled heat and oxygen supply, the tool is consumed in a predictable manner through oxidation, transforming the harmful random fragmentation into a useful controlled consumption process that reliably removes the tool.

Inventive Principle:

Principle #22Blessing in disguise (Convert harm into benefit)

3Reliability

If complex retrieval operations are used to remove downhole tools, then tools can be recovered, but device complexity and operational costs increase

Engineering Contradiction:

Core Design Contradiction:

ReliabilityVSDevice complexity

Solution Approach 1:

The patent extracts the tool removal function from complex mechanical retrieval operations. Instead of using complex equipment to physically retrieve and extract the tool, the system extracts the tool material itself through combustion, converting it into ash and gases that naturally fall to the bottom of the well bore. This eliminates the need for complex retrieval machinery and operations.

Inventive Principle:

Principle #2Taking out (Extraction)

Solution Approach 2:

The downhole tool is designed with consumable material that can be consumed by the torch assembly. The tool essentially serves itself by being consumed through the combustion process, eliminating the need for external retrieval equipment. The tool's own material becomes the fuel for its removal, creating a self-service removal mechanism.

Inventive Principle:

Principle #25Self-service

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

This method enables cost-effective and time-efficient removal of downhole tools by ensuring consistent structural failure and elimination of the need for surface intervention, reducing operational complexity and costs associated with conventional retrieval methods.

Implementation Method 1

a torch with a fuel load that produces the heat and source of oxygen when burned

Methodology Applied

Scientific EffectCombustion: Combustion

Implementation Method 2

the fuel load comprises thermite

Methodology Applied

Scientific EffectThermal energy production: Exothermic Reaction

Implementation Method 3

the magnesium metal is converted to magnesium oxide when exposed to heat and a source of oxygen

Methodology Applied

Scientific EffectOxidation: Oxidation

Data Source

PatentUS8291970B2Consumable downhole tools

Publication Date: 2012.10.23

AI summary

A downhole tool having a body or structural component comprises a material that is at least partially consumed when exposed to heat and a source of oxygen. The material may comprise a metal, such as magnesium, which is converted to magnesium oxide when exposed to heat and a source of oxygen. The downhole tool may further comprise a torch with a fuel load that produces the heat and source of oxygen when burned. The fuel load may comprise a flammable, non-explosive solid, such as thermite.