Mechanically Modified Filter Cake for Wellbore Sealing

Solution Overview

Problem

Current drilling technologies face challenges in forming an optimized filter cake that reduces permeability and prevents differential sticking, leading to increased drilling time and costs due to premature filter cake formation and imperfections in encapsulated delivery systems.

Innovation Solution

A downhole tool with a compression device that applies mechanical pressure to the wellbore sidewalls using extendable support members and rotatable compression surfaces, which can break encapsulated particles and compress the filter cake, reducing its permeability and enhancing sealing properties.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If polymeric additives are used to form a filter cake, then fluid loss control is improved, but the filter cake permeability may be insufficiently reduced and differential sticking occurs

Engineering Contradiction:

Improvefluid loss controlVSAvoiddifferential sticking

Core Design Contradiction:

ReliabilityVSObject-affected harmful factors

Solution Approach 1:

The patent applies mechanical compression to change the physical state and density of the filter cake, transforming it from a loose, high-permeability structure to a compact, low-permeability structure. This parameter change in density and permeability prevents differential sticking while maintaining fluid loss control.

Inventive Principle:

Principle #35Parameter changes

Solution Approach 2:

The patent replaces the chemical mechanism (polymeric additives forming filter cake) with a mechanical mechanism (compression device applying lateral force) to achieve the desired filter cake properties. The mechanical compression device physically densifies the filter cake to reduce permeability and prevent sticking.

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

2Stability of the object's composition

If drilling fluid density is increased to provide hydrostatic pressure, then wellbore stability is improved, but the risk of differential sticking increases

Engineering Contradiction:

Improvewellbore stabilityVSAvoiddifferential sticking

Core Design Contradiction:

Stability of the object's compositionVSObject-affected harmful factors

Solution Approach 1:

The patent applies local mechanical compression to the filter cake at the wellbore wall, creating a zone of reduced permeability precisely where needed. This localized treatment allows the use of appropriate drilling fluid density for wellbore stability without the harmful effect of differential sticking in the compressed zone.

Inventive Principle:

Principle #3Local quality

3Manufacturing precision

If encapsulated particles are used for localized application, then precision is improved, but premature breaking and reliability issues occur

Engineering Contradiction:

Improvelocalized application precisionVSAvoidpremature breaking

Core Design Contradiction:

Manufacturing precisionVSReliability

Solution Approach 1:

The patent introduces a mechanical compression device as an intermediary that applies controlled lateral force to break encapsulated particles at the intended location and time. This intermediary mechanism ensures particles break only when needed, preventing premature breaking while achieving localized application precision.

Inventive Principle:

Principle #24Intermediary (Mediator)

Solution Approach 2:

The encapsulated particles are prepared in advance with a controlled breaking mechanism, and the compression device is positioned and activated preliminarily to ensure breaking occurs at the precise moment and location needed, preventing premature activation while ensuring reliable breakdown when required.

Inventive Principle:

Principle #10Preliminary action

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 results in a less permeable filter cake, reducing the likelihood of differential sticking and increasing drilling efficiency by quickly sealing the wellbore and maintaining a stable drilling environment, thus reducing downtime and costs.

Implementation Method 1

A downhole tool with a compression device that applies mechanical pressure to the wellbore sidewalls using extendable support members and rotatable compression surfaces, which can break encapsulated particles and compress the filter cake, reducing its permeability and enhancing sealing properties.

Methodology Applied

Scientific EffectMechanical pressure: Compression

Implementation Method 2

A downhole tool with a compression device that applies mechanical pressure to the wellbore sidewalls using extendable support members and rotatable compression surfaces, which can break encapsulated particles and compress the filter cake

Methodology Applied

Scientific EffectMechanical force: Mechanical Force

Data Source

PatentUS9140075B2Mechanically modified filter cake

Publication Date: 2015.09.22 M I LLC(US)

AI summary

A down hole tool including a compression surface, a compression surface axis, and at least one support member configured to attach the compression surface to a well drilling tool assembly, wherein the extendable support member is extendable by an extension force provided to the support member. The down hole tool is rotable relative to an axis of the well drilling tool assembly, and as the well drilling tool assembly rotates, the at least one compression device exerts a lateral force along a sidewall of a wellbore. Also, a method of forming filter cake comprising releasing a drilling fluid and contacting the drilling fluid with a mechanical pressure on the sidewall of the wellbore and the drilling fluid.