Segmented Fin Centralizer for Wellbore Alignment and Flow

Solution Overview

Problem

Existing centralizers in subterranean wellbores often obstruct fluid flow, cause differential sticking, and result in incomplete cement seals due to channeling flow and limited contact points, making it difficult to maintain liner alignment, especially in curved or horizontal sections.

Innovation Solution

A centralizer apparatus with discrete fin modules arranged in a stack that transitions between a screw-state and a fanned-out-state, utilizing a screwing action to reduce sticking and enhance fluid flow, and a fanned-out configuration to support and mix cement effectively, providing multiple contact points for improved alignment and cement displacement.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Stability of the object's composition

If traditional centralizers are used to maintain liner alignment, then alignment is improved, but fluid flow is obstructed causing higher pumping pressures

Engineering Contradiction:

Improveliner alignmentVSAvoidpumping pressure

Core Design Contradiction:

Stability of the object's compositionVSLoss of energy

Solution Approach 1:

The centralizer is divided into multiple discrete fin modules (e.g., 4-12 modules) stacked around the liner, each module independently contributing to alignment while allowing fluid to pass through the gaps between modules. This segmentation maintains alignment functionality while reducing flow obstruction compared to a solid traditional centralizer.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The fin modules are designed to be rotatable relative to each other, transforming from a static structure to a dynamic one. When drilling fluid flows through the annular space, it exerts torque on the fins, causing them to rotate and align with the flow direction, thereby reducing resistance and pumping pressure while maintaining alignment capability.

Inventive Principle:

Principle #15Dynamics

2Stability of the object's composition

If traditional centralizers with limited contact points are used, then alignment is maintained, but differential sticking occurs due to channeling flow

Engineering Contradiction:

Improveliner alignmentVSAvoiddifferential sticking

Core Design Contradiction:

Stability of the object's compositionVSReliability

Solution Approach 1:

The centralizer is divided into multiple discrete fin modules (e.g., 4-12 modules) stacked around the liner, each module independently contributing to alignment while allowing fluid to pass through the gaps between modules. This segmentation maintains alignment functionality while reducing flow obstruction compared to a solid traditional centralizer.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The fin modules are designed to be rotatable relative to each other, transforming from a static structure to a dynamic one. When drilling fluid flows through the annular space, it exerts torque on the fins, causing them to rotate and align with the flow direction, thereby reducing resistance and pumping pressure while maintaining alignment capability.

Inventive Principle:

Principle #15Dynamics

3Stability of the object's composition

If traditional centralizers are used in curved or horizontal wellbore sections, then alignment is attempted, but the centralizer presents difficulties due to gravity and geometry

Engineering Contradiction:

Improveliner alignmentVSAvoiddeployment difficulty

Core Design Contradiction:

Stability of the object's compositionVSEase of operation

Solution Approach 1:

The fin modules are designed to be rotatable relative to each other, transforming from a static structure to a dynamic one. When drilling fluid flows through the annular space, it exerts torque on the fins, causing them to rotate and align with the flow direction, thereby reducing resistance and pumping pressure while maintaining alignment capability.

Inventive Principle:

Principle #15Dynamics

Solution Approach 2:

The centralizer's geometry is changed from a static fixed configuration to a dynamic adjustable configuration. The fin modules can rotate to different angular positions, allowing the centralizer to adapt its orientation and contact points with the wellbore wall, facilitating deployment in curved and horizontal sections where gravity and wellbore geometry present challenges.

Inventive Principle:

Principle #35Parameter changes

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 apparatus reduces differential sticking, facilitates efficient fluid flow, and ensures a complete cement seal by maintaining tubular alignment and promoting cement mixing and reinforcement, even in challenging wellbore orientations.

Implementation Method 1

rotating the centralizer causes the fin modules to align into a screw-shaped state... The screw-shaped state facilitates a larger flow path that can reduce differential sticking

Methodology Applied

Scientific EffectScrew mechanism: Screw

Implementation Method 2

The swirling motion of the discontinuous auger-shaped structure's fin blades can facilitate a larger fluid flow path that also directs the fluid around the entire wellbore

Methodology Applied

Scientific EffectSwirling flow: Vortex Ring

Implementation Method 3

rotating the centralizer fans out the fin blades into multiple high surface area blades, e.g., a fanned-out-state, that can help support and centralize the tubular

Methodology Applied

Scientific EffectMechanical support:

Implementation Method 4

the fin blades can facilitate cleaning by cementing pre-treatments, e.g., by forcing cleaning pills to swirl and scour the mud cake clear before the cement lands

Methodology Applied

Scientific EffectSwirling motion: Vortex Ring

Implementation Method 5

rotating the centralizer in one rotational direction creates a screwing action which can help draw a tubular (e.g., a liner or casing) into the wellbore formation, analogous to a drywall screw

Methodology Applied

Scientific EffectScrew action: Screw

Data Source

PatentUS11131154B2Formation screw and centralizer

Publication Date: 2021.09.28 HALLIBURTON ENERGY SERVICES INC

AI summary

A centralizer apparatus for deployment in a subterranean wellbore, including a tubular adapted to be deployed in the subterranean wellbore such that a long axis of the tubular is parallel to a portion wellbore and a stack of fin modules stacked parallel to the long axis of the tubular. Each one of the fin modules includes a hub having an opening adapted to fit around the outer surface of the tubular, the hub including a stop structure configured to restrict the rotation of adjacent ones of the fin modules in the stack of fin module, and, one or more fin blades projecting from an outer surface of the hub. Rotating the tubular in one rotational direction aligns the fin modules into a screw-shaped state such that the one or more fin blades of adjacently stacked fin modules are progressively offset in a rotational direction perpendicular to the long axis of the tubular. Rotating the tubular in an opposite direction disperses the fin modules into a fanned-out state, such that the one or more fin blades of adjacently stacked fin modules are maximally offset as allowed by the stop structures.