Expandable Pack-off Element for Wellbore Liner Sealing
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional liner hanger systems fail to effectively address failures in expandable liners, leading to unisolated annuli and requiring costly sidetrack operations and rig downtime, especially in deviated or horizontal wells where gravity supports liner weight, necessitating a more robust and efficient sealing solution.
Innovation Solution
A downhole tool system with a centralizer and a pack-off element that uses fluid pressure to adjust and seal the liner top to the wellbore wall, eliminating the need for conventional liner hangers and top packers in non-reservoir sections, allowing for quick installation and effective sealing in challenging well geometries.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If conventional liner hanger systems are used, then the system structure is simple, but the system cannot effectively seal the wellbore when expandable liners fail, requiring costly sidetrack operations
Solution Approach 1:
The patent employs dynamically expandable components including an expandable centralizer and an expandable pack-off element that can be actuated from a compressed state to an expanded state through fluid pressure. This allows the system to adapt its configuration based on operational needs, providing reliable sealing when required while maintaining a compact form during transport and installation.
Solution Approach 2:
The system utilizes fluid pressure (pneumatics/hydraulics) to actuate the expandable centralizer and pack-off element. Fluid pressure is supplied through the bore to expand these components, enabling them to contact the wellbore wall and create effective seals without requiring complex mechanical actuation systems.
2Productivity
If conventional liner hanger systems are used, then the equipment cost is lower, but rig non-productive time increases due to failed liner remediation
Solution Approach 1:
The system is designed to remediate liner failures through self-contained operations. The expandable centralizer and pack-off element can be actuated in-situ to restore sealing capability without requiring retrieval of the liner or execution of sidetrack operations, allowing the well to return to productive status quickly.
Solution Approach 2:
The system includes preliminary sealing capability through the pack-off element that can be deployed to seal the annulus above a failed liner. This preliminary action prevents further fluid loss and stabilizes the wellbore, enabling subsequent remedial operations to proceed efficiently without extending rig downtime.
3Adaptability or versatility
If conventional liner hanger systems are used, then the installation process is simpler, but the system cannot effectively operate in deviated or horizontal wells
Solution Approach 1:
The expandable centralizer dynamically adapts to different wellbore geometries including vertical, deviated, and horizontal sections. By expanding to contact the wellbore wall, it provides stabilization and positioning capabilities across various well angles, eliminating the need for gravity-dependent installation methods.
Solution Approach 2:
The system changes its physical parameters (radial dimension) through expansion to adapt to different wellbore conditions. The expandable components can adjust their outer diameter to match the wellbore size, providing effective operation across different well geometries and depths.
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 system provides a simple, robust, and cost-effective solution for sealing the liner top, reducing rig non-productive time and well equipment costs, and effectively operates in deviated or horizontal wells by utilizing fluid pressure to expand and engage the pack-off element with the wellbore wall, thereby ensuring reliable zonal isolation.
Implementation Method 1
the centralizer expandable to contact a wellbore wall and adjust a location of the downhole tool system relative to the wellbore wall based on a first fluid pressure supplied through the bore
Implementation Method 2
the pack-off element expandable to at least partially seal a liner top of the wellbore liner to the wellbore wall based on a second fluid pressure supplied through the bore
Data Source
AI summary
A downhole tool system includes a base tubular that includes a bore therethrough; a centralizer positioned to ride on the base tubular, the centralizer expandable to contact a wellbore wall and adjust a location of the downhole tool system relative to the wellbore wall based on a first fluid pressure supplied through the bore; and a liner top assembly positioned to ride on the base tubular, the liner top assembly including a wellbore liner and a pack-off element, the pack-off element expandable to at least partially seal a liner top of the wellbore liner to the wellbore wall based on a second fluid pressure supplied through the bore.