Downhole Stress Test Tool Fluid Isolation

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Existing methods for hydraulic fracturing in geological formations face issues such as premature pump module failure due to contamination from formation or drilling mud fluids, inadequate viscosity leading to high leak-off rates, and adverse reactions between fluids and formations, which hinder accurate stress testing and increase exploration costs.

Innovation Solution

A downhole tool with a container to store and transport a specifically selected fracturing fluid, isolated from other fluids, which is more viscous than formation or drilling mud fluids, allowing for reliable pump operation and effective pressure build-up, while avoiding adverse reactions with the formation.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If formation or drilling mud fluids are used for hydraulic fracturing, then the pump module operates, but the pump module fails prematurely due to contamination

Engineering Contradiction:

Improvepump module reliabilityVSAvoidfluid contamination

Core Design Contradiction:

ReliabilityVSObject-generated harmful factors

Solution Approach 1:

The system separates the fracturing fluid from formation and drilling mud fluids by using a dedicated container and pump assembly. The fracturing fluid is stored in a separate container and pumped through a separate pathway, isolating it from contaminants in the wellbore environment. This segmentation prevents contamination of the fracturing fluid while allowing the pump module to operate reliably.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The container and pump assembly act as an intermediary system between the fracturing fluid source and the formation. This intermediary protects the fracturing fluid from direct contact with formation fluids and drilling mud, preventing contamination while still enabling the hydraulic fracturing function to be performed.

Inventive Principle:

Principle #24Intermediary (Mediator)

2Loss of energy

If less viscous fluids are used for hydraulic fracturing, then fluid flow is easier, but leak-off rate increases

Engineering Contradiction:

Improvefluid leak-offVSAvoidfluid pumping

Core Design Contradiction:

Loss of energyVSEase of operation

Solution Approach 1:

The system changes the viscosity parameter of the fracturing fluid by selecting fluids with higher viscosity than traditional drilling mud or formation fluids. This increased viscosity reduces the leak-off rate into the formation while the dedicated pump assembly compensates for the higher pumping requirements, maintaining effective fluid delivery to the formation for stress testing.

Inventive Principle:

Principle #35Parameter changes

3Reliability

If standard fluids are used for hydraulic fracturing, then the procedure is simple, but adverse reactions occur with the formation

Engineering Contradiction:

Improvestress testing accuracyVSAvoidadverse formation-fluid reactions

Core Design Contradiction:

ReliabilityVSObject-affected harmful factors

Solution Approach 1:

The system applies local quality by selecting fracturing fluids with specific properties tailored to the formation type and stress testing requirements. Different fracturing fluids can be used for different formation conditions, and the fluid selection is localized to the specific wellbore environment and formation characteristics, preventing adverse reactions while maintaining testing accuracy.

Inventive Principle:

Principle #3Local quality

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

The solution enhances the reliability and lifespan of pump modules, reduces fluid leak-off, and enables accurate stress testing with improved pressure differentials, thereby reducing exploration costs and enhancing the accuracy of stress measurements.

Implementation Method 1

pump configured to pump the fracturing fluid into the first and second packers to inflate the first and second packers and to pump the fracturing fluid into the annular region to induce a fracture of the geological formation

Methodology Applied

Scientific EffectHydraulic pressure: Pressure Increase

Implementation Method 2

first and second packers selectively inflatable to form a sealed annular region around the downhole tool... pump configured to pump the fracturing fluid into the first and second packers to inflate the first and second packers

Methodology Applied

Scientific EffectFluid pressure expansion: Pressure Increase

Data Source

PatentUS8146416B2Methods and apparatus to perform stress testing of geological formations

Publication Date: 2012.04.03 SCHLUMBERGER TECH CORP

AI summary

Example methods and apparatus to perform stress testing of geological formations are disclosed. A disclosed example downhole stress test tool for pressure testing a geological formation comprises first and second packers selectively inflatable to form an annular region around the tool, a container configured to store a fracturing fluid, wherein the fracturing fluid is different than a formation fluid and a drilling fluid, a pump configured to pump the fracturing fluid into the first and second packers to inflate the first and second packers and to pump the fracturing fluid into the annular region to induce a fracture of the geological formation, and a sensor configured to detect a pressure of the fracturing fluid pumped into the annular region corresponding to the fracture of the geological formation.