External Slip Expansion Slots Retainer Mechanism

Solution Overview

Problem

Existing packer assemblies and external slips face challenges in easy installation and retrieval without breaking into segments, and in providing a uniform grip in wellbore applications, especially due to issues with premature expansion from fluid flow or debris.

Innovation Solution

The design incorporates an external slip with expansion slots and a retainer mechanism that allows for controlled radial expansion, preventing premature expansion and ensuring a uniform grip without segmenting, facilitated by a wedge system that engages with the slip to maintain a seal and allow for easy installation and retrieval.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If traditional external slips are used, then installation and retrieval are simple, but premature expansion occurs due to fluid flow or debris causing non-uniform grip

Engineering Contradiction:

Improvegrip uniformityVSAvoidpremature expansion

Core Design Contradiction:

ReliabilityVSObject-affected harmful factors

Solution Approach 1:

The slip body is divided into multiple segments separated by expansion slots, allowing controlled radial expansion. The segments can expand independently to accommodate irregularities in the wellbore while maintaining uniform grip, preventing premature expansion caused by fluid flow or debris.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The slip transitions from a static structure to a dynamic one with movable segments that can expand and contract. The expansion slots enable the segments to move radially outward when needed for gripping, and return to their original position for retrieval, providing adaptive response to wellbore conditions.

Inventive Principle:

Principle #15Dynamics

2Reliability

If expansion slots are added to prevent premature expansion, then grip uniformity improves, but device complexity increases

Engineering Contradiction:

Improvegrip uniformityVSAvoidslip structure

Core Design Contradiction:

ReliabilityVSDevice complexity

Solution Approach 1:

The slip body is divided into multiple segments separated by expansion slots, allowing controlled radial expansion. The segments can expand independently to accommodate irregularities in the wellbore while maintaining uniform grip, preventing premature expansion caused by fluid flow or debris.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The slip body is designed as a flexible structure with expansion slots that allow it to deform radially. This flexibility enables the slip to expand uniformly around the wellbore while maintaining structural integrity, achieving reliable grip without complex mechanical components.

Inventive Principle:

Principle #30Flexible shells and thin films

3Reliability

If the slip is designed to expand radially for better gripping, then grip uniformity improves, but the slip may break into segments during setting

Engineering Contradiction:

Improvegrip uniformityVSAvoidslip integrity

Core Design Contradiction:

ReliabilityVSStability of the object's composition

Solution Approach 1:

The slip body is divided into multiple segments separated by expansion slots, allowing controlled radial expansion. The segments can expand independently to accommodate irregularities in the wellbore while maintaining uniform grip, preventing premature expansion caused by fluid flow or debris.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The expansion slots are pre-positioned and sized to allow controlled expansion during the setting process. This preliminary design ensures that the slip expands in a controlled manner rather than breaking apart, maintaining structural integrity while achieving the desired grip uniformity.

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

This solution enables efficient and cost-effective setting and retrieval of packer assemblies with improved grip uniformity, preventing premature expansion and maintaining the integrity of the slip during deployment and retrieval processes.

Implementation Method 1

a wedge capable of, in a set position, (i) engaging the internal surface of the slip; and (ii) transferring a force to the slip in a direction capable of expanding the slip radially outward

Methodology Applied

Scientific EffectMechanical Force: Mechanical Force

Data Source

PatentUS10196870B2External slip having expandable slots and a retainer

Publication Date: 2019.02.05 HALLIBURTON ENERGY SERVICES INC

AI summary

An external slip includes a slip body comprising a wall having internal and external surfaces. The internal surface includes a ramp portion, and a plurality of teeth is disposed on the external surface of the wall of the slip body. A plurality of expansion slots extends through a thickness of the wall, at least one extending from a first end of the wall toward a second end of the wall but not reaching the second end. At least another of the plurality of expansion slots extends from the second end toward the first end of the wall but does not reach the first end. An installation slot extends through a thickness of the wall along a length of the wall, and a retainer is coupled to first and second gap ends of the wall across a gap created by the installation slot.