Hydrostatically Insensitive Plug Assembly for Wellbore Operations
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current plug assemblies for wellbore operations face challenges in selectively sealing the casing during cementing operations and pressure testing, requiring lengthy and costly processes for reestablishing fluid communication after integrity testing.
Innovation Solution
The proposed plug assembly includes a plug unit with a longitudinal bore and a valve unit featuring one-way valve sub-assemblies and a shearable external sleeve, allowing for selective sealing and fluid communication by adjusting pressure differentials to open or close fluid paths, facilitating efficient cementing and pressure testing without the need for lengthy plug removal or perforation operations.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a plug assembly is used to seal the casing during pressure testing, then casing integrity can be tested, but reestablishing fluid communication requires lengthy and costly plug removal or perforation operations
Solution Approach 1:
The plug assembly incorporates a dynamic sleeve that can move between positions to selectively open or close fluid pathways. The sleeve is actuated by pressure differentials created during testing operations, transforming the static plug into a dynamic device that can reversibly control fluid flow without removal or permanent modification
Solution Approach 2:
The system utilizes pressure differential as a control parameter to trigger sleeve movement. By changing the pressure state during testing, the plug assembly transitions between sealed and open configurations, enabling reversible sealing without mechanical intervention
2Reliability
If a plug assembly is used to seal the casing during pressure testing, then casing integrity can be tested, but plug removal or perforation operations are costly
Solution Approach 1:
The dynamic sleeve mechanism allows the plug to reversibly seal and open, eliminating the need for expensive removal operations or perforation workovers. The same device that provides sealing can be actuated to restore flow, reducing operational costs
Solution Approach 2:
The plug assembly is self-actuating through pressure differentials created during normal testing operations. The system uses the testing process itself to trigger the opening mechanism, eliminating the need for separate expensive intervention operations
3Adaptability or versatility
If a shearable external sleeve is used to control fluid pathways, then selective sealing and fluid communication can be achieved, but the device complexity increases
Solution Approach 1:
The external sleeve acts as an intermediary element between the pressure differential and the internal valve components. It translates pressure changes into mechanical movement that controls fluid pathways, providing a simple interface for complex functionality
Solution Approach 2:
The valve unit is segmented into modular components (external sleeve, internal valve elements, shearable connections) that can independently function. This segmentation allows each component to perform a specific function while maintaining overall system versatility
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 cementing operations and pressure testing by allowing selective sealing and fluid communication, reducing the need for costly plug removal and perforation processes, thereby enhancing operational efficiency and reducing costs.
Implementation Method 1
a biasing member disposed within the plug assembly and configured to bias the external valve sleeve towards the open position
Implementation Method 2
a first one-way valve sub-assembly providing pressure communication from the exterior of the plug assembly above the plug unit to the valve chamber
Data Source
AI summary
A plug assembly having valve chamber chargeable with pressure from above or below the plug assembly. The charged chamber is used to selectively move an external sleeve to open fluid communication between the tubular above and below the plug assembly.