Differential Slip Mechanism for Oval Casing Engagement
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Casing ovality in wellbore applications can lead to uneven contact of frac plug slips with the casing, resulting in inadequate sealing and potential leaks or blowouts due to insufficient support from some slips.
Innovation Solution
A slip assembly with a mechanism allowing individual slips to move radially outward different amounts, ensuring full engagement with an oval or out-of-round casing, using a cone and setting ring with deformable elements to accommodate varying radial movement and secure contact.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a frac plug is set in an oval section of casing, then the slips may contact the casing unevenly, but this results in insufficient support and potential seal failure
Solution Approach 1:
The slip assembly incorporates a mechanism that allows individual slips to move radially outward by different amounts, transforming the static slip configuration into a dynamic system that can adapt to oval casing geometry. This enables each slip to independently engage the casing at its optimal position, ensuring uniform support and seal integrity even when the casing is out of round.
Solution Approach 2:
The invention applies different radial movement characteristics to individual slips based on their local engagement requirements with the oval casing. Each slip can move radially outward by a different amount, allowing local adaptation to the varying casing geometry around the circumference, thereby ensuring that each slip provides adequate support at its specific engagement point.
2Reliability
If slips are forced radially outward to engage oval casing, then individual slips require different movement amounts, but this increases the complexity of the slip assembly mechanism
Solution Approach 1:
The slip assembly is divided into multiple independent slip units, each capable of radial movement. The segmentation allows each slip to be independently actuated and controlled, with each slip having its own movement mechanism that can be triggered sequentially or simultaneously based on engagement requirements, thereby managing complexity through modular independence.
Solution Approach 2:
The invention changes the radial position parameter of individual slips dynamically during the setting process. By controlling the radial movement distance of each slip independently, the system adapts to the oval casing geometry, allowing slips to engage at different radial positions rather than requiring uniform engagement, thus simplifying the overall mechanism design.
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 slip assembly ensures secure engagement of all slips with the casing, enhancing the seal integrity and preventing leaks or blowouts by allowing differential radial movement to compensate for casing irregularities.
Implementation Method 1
a mechanism which allows different amounts of radial movement of individuals slips to ensure sufficient setting of the individual slips when the surrounding tubing is oval or otherwise out of round
Data Source
AI summary
A technique facilitates operation of a slip assembly, e.g. a frac plug assembly, having a plurality of slips. The plurality of slips may selectively be forced in a radially outward direction via, for example, a cone so as to set the slips against a surrounding casing or other tubing. The slip assembly further comprises a mechanism which allows different amounts of radial movement of individuals slips to ensure sufficient setting of the individual slips when the surrounding tubing is oval or otherwise out of round.