Retrievable Cement Bushing With Movable Engagement Lugs

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing well completion technologies face challenges in maintaining pressure containment during cementing operations, particularly in preventing cement backup and ensuring reliable sealing and pressure integrity, especially when dealing with differential pressures and axial movements.

Innovation Solution

A retrievable cement bushing system with a body having an internal longitudinal passage, featuring engagement lugs that move radially outward for engagement with a surrounding wall and a sleeve that moves inward to protect the slick joint from loading, ensuring a secure seal and preventing premature release, while allowing for easy retrieval.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If the engagement lug is made movable to engage with the surrounding wall for pressure containment, then the seal integrity is improved, but the device complexity increases due to the movable mechanism

Engineering Contradiction:
Improveseal integrityVSAvoiddevice complexity
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The engagement lug is designed as a movable component that can transition between retracted and engaged positions. This dynamic feature allows the lug to engage with the surrounding wall to provide pressure containment and seal integrity when needed, while potentially being retracted when not required, thus resolving the contradiction between reliability and device complexity.

Inventive Principle:
Principle #15Dynamics

2Reliability

If the sleeve is moved to protect the slick joint from loading, then the reliability is improved, but the ease of operation deteriorates due to additional movement requirements

Engineering Contradiction:
Improveprotection from loadingVSAvoidease of operation
Core Design Contradiction:
ReliabilityVSEase of operation

Solution Approach 1:

The sleeve is configured as a movable component that can shift position to either expose or protect the slick joint from loading forces. This dynamic protection mechanism improves reliability by shielding the slick joint when engaged, while the movement capability allows for operational flexibility, balancing reliability improvement with operational ease.

Inventive Principle:
Principle #15Dynamics

3Reliability

If the engagement lug is held in the radially outward position for engagement, then the pressure containment is improved, but the force required for retrieval increases

Engineering Contradiction:
Improvepressure containmentVSAvoidretrieval force
Core Design Contradiction:
ReliabilityVSForce

Solution Approach 1:

The engagement lug's movable design allows it to be held in the radially outward engaged position during pressure containment operations, providing reliable sealing. The same movability enables the lug to be retracted or disengaged during retrieval, reducing the force required for removal and resolving the contradiction between pressure containment and retrieval effort.

Inventive Principle:
Principle #15Dynamics

Data Source

PatentEP3134606B1Retrievable cement bushing system and methodology
Publication Date: 2020.02.05 SERVICES PETROLIERS SCHLUMBERGER SA
  • EP3134606B1 patent drawingFigure 1
  • EP3134606B1 patent drawingFigure 2
  • EP3134606B1 patent drawingFigure 3

AI summary

A technique facilitates pressure containment with a retrievable cement bushing. The retrievable cement bushing comprises a body having an internal longitudinal passage. Additionally, the retrievable cement bushing comprises an engagement lug which cooperates with a sleeve. The engagement lug is mounted on the body and is movable to a radially outward position for engagement with a corresponding portion of a surrounding wall, e.g an internal packer wall. The sleeve is sized to receive a slick joint therethrough and is movable to a radially inward position relative to the engagement lug so as to hold the engagement lug in the radially outward position. The sleeve protects the slick joint from inwardly directed loading via the engagement lug when the retrievable cement bushing is subjected to differential pressures.