Threaded Packing Spacer Ring Extrusion Barrier Design

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Existing compression set retrievable packers face issues with extrusion barriers failing due to high flow velocities during fluid replacement, leading to distortion and ineffective sealing, as well as difficulties in removal due to embedded extrusion rings.

Innovation Solution

An extrusion ring is attached to a mandrel end with a gage ring and a softer ring between the extrusion ring and the mandrel, which acts as an extrusion barrier, preventing relative motion and maintaining concentricity, and extends to protect the sealing element from the extrusion ring during setting.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Adaptability or versatility

If a wire mesh ring is made soft to move with the sealing element during setting, then the sealing element can properly engage the surrounding tubular, but the wire mesh is pushed into the extrusion gap by high velocity fluids causing damage and failure

Engineering Contradiction:

Improveability of extrusion ring to move with sealing elementVSAvoidintegrity of extrusion ring under high velocity flow

Core Design Contradiction:

Adaptability or versatilityVSReliability

Solution Approach 1:

The extrusion barrier is divided into two separate components: a soft extrusion ring and a harder backup ring. The soft ring moves with the sealing element during setting while the backup ring remains stationary to resist high velocity fluid forces. This segmentation allows each component to perform its specific function without compromising the other.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The system uses two different materials with contrasting properties: a soft, flexible material for the extrusion ring that can deform and move, and a harder, more rigid material for the backup ring that resists deformation. This composite approach combines the advantages of both material properties in a single extrusion barrier system.

Inventive Principle:

Principle #40Composite materials

2Reliability

If overlapping extrusion rings are used to protect the sealing element ends, then extrusion protection is provided, but the sealing element climbs over the rings during setting causing the extrusion barrier to fail

Engineering Contradiction:

Improveextrusion protection capabilityVSAvoidproper engagement of sealing element

Core Design Contradiction:

ReliabilityVSEase of operation

Solution Approach 1:

Instead of having the extrusion ring extend beyond the sealing element to overlap and protect it (the conventional approach), the backup ring is positioned to extend beyond the sealing element in the opposite direction - away from the sealing element. This inverted positioning prevents the sealing element from climbing over the rings while still providing extrusion protection through the combination of rings.

Inventive Principle:

Principle #13The other way round (Inversion)

3Strength

If the extrusion ring assembly is made stiff to resist high velocity fluids, then the ring can maintain its shape, but the sealing element climbs over the ring during setting preventing the extrusion barrier from engaging the surrounding tubular

Engineering Contradiction:

Improveresistance to high velocity fluid forcesVSAvoidability to move with sealing element during setting

Core Design Contradiction:

StrengthVSAdaptability or versatility

Solution Approach 1:

The extrusion barrier is segmented into a soft extrusion ring that moves with the sealing element and a stiff backup ring that resists fluid forces. This segmentation resolves the contradiction by assigning different mechanical properties to different components based on their specific functional requirements.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The backup ring acts as an intermediary element between the soft extrusion ring and the surrounding tubular. It provides the necessary structural support and resistance to high velocity fluids while allowing the soft ring to perform its extrusion protection function without being compromised by fluid forces.

Inventive Principle:

Principle #24Intermediary (Mediator)

4Reliability

If the extrusion ring extends beyond the sealing element to provide protection, then extrusion barrier function is enhanced, but the ring embeds into the sealing element during setting making removal difficult

Engineering Contradiction:

Improveextrusion barrier effectivenessVSAvoidpacker removal difficulty

Core Design Contradiction:

ReliabilityVSEase of repair

Solution Approach 1:

The backup ring extends beyond the sealing element in the opposite direction from the extrusion ring, creating a configuration where the rings work together without embedding. The extrusion ring protects the sealing element from extrusion while the backup ring provides structural support, and neither embeds into the sealing element during setting or removal.

Inventive Principle:

Principle #13The other way round (Inversion)

Data Source

PatentUS10443343B2Threaded packing element spacer ring

Publication Date: 2019.10.15 BAKER HUGHES CO

AI summary

An extrusion ring is attached at a mandrel end to a gage ring as well as a softer ring that is disposed between the extrusion ring and the mandrel. The softer ring acts as an extrusion barrier along the mandrel. On setting the softer ring protects a free end of an extrusion ring from contact with the sealing element by extending axially at least as far as the extrusion ring and preferably further. The sealing element being softer than the adjacent softer ring allows the extrusion ring to push the softer ring out past the end of the extrusion ring and allows the softer ring to fill a void space adjacent the free end of the extrusion ring and to the sealing element. Relative motion between the rings at the attachment location is prevented.