Fracturing Valve Piston Mechanism for Wellbore Flow Access
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing down-hole valve subassemblies for well fracturing suffer from restricted fluid flow and well bore constriction due to progressively decreasing diameters, limiting production and requiring costly and time-consuming drill-outs for access.
Innovation Solution
A fracturing valve apparatus with a tubular valve body, piston valve, and ball seat sub-assembly that allows for increased fluid flow by moving the piston valve from a raised to a lowered position under downward force, using ratchet rings or fingers for holding mechanisms, and a removal tool for easy disassembly, enabling higher flow rates and full well access.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of operation
If progressively smaller diameter valve seats are used in successive valve subs, then the ball valve mechanism can selectively close individual stages, but the fluid flow rate becomes increasingly restricted
Solution Approach 1:
The valve subassembly is divided into separate functional components: a ball valve mechanism for selective closure and a piston valve mechanism for flow control. This segmentation allows the ball valve to provide stage isolation while the piston valve with its larger opening maintains high flow capacity when open.
Solution Approach 2:
The piston valve dynamically changes the flow path from a restricted state (when closed) to an open state with significantly increased flow capacity. The piston moves between positions to either block or fully open the flow path, providing dynamic flow control without the permanent restriction of progressively smaller valve seats.
2Reliability
If ball valve seat mechanisms are left in the well bore, then stage isolation is maintained, but the well bore is constricted preventing full production and conventional tool access
Solution Approach 1:
The ball and ball seat components are extracted from the well bore after the fracturing operation is complete. The system is designed to allow retrieval of these components through the tubing, eliminating the permanent obstruction they would otherwise create and restoring full well bore access for production and conventional tool operations.
Solution Approach 2:
The ball valve seat mechanism is temporarily deployed during the fracturing operation to provide stage isolation, then subsequently recovered and removed from the well bore. This temporary deployment and recovery approach maintains isolation reliability during operation while eliminating well bore constriction afterward.
3Ease of operation
If drill-outs are performed to remove balls and seats, then full production access is achieved, but the process is costly and time consuming
Solution Approach 1:
The mechanical drill-out process is replaced with a simpler mechanical retrieval system. Instead of using drilling equipment to remove the ball and seat, a retrieval tool is deployed through the tubing to mechanically extract these components, significantly reducing the time and cost required while achieving the same goal of restoring full well bore access.
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 solution enhances fluid flow rates and allows for full well access without the need for costly drill-outs, enabling efficient fracturing and production operations.
Implementation Method 1
The ball seat sub-assembly is configured to move the piston valve from the raised position to the lowered position when downward force is applied to the ball seat sub-assembly
Implementation Method 2
injecting pressurized fracturing fluid into the tubing string wherein the fracturing fluid moves the ball through the tubing string into the apparatus until the ball is seated on the ball seat sub-assembly
Data Source
AI summary
Apparatus and methods are provided for fracturing a well in a hydrocarbon bearing formation. The apparatus can include one or more valve sub-assemblies assembled into a tubing string inserted into an unlined well. The valve sub-assembly can include a sliding piston initially pinned in place to seal off ports that provide communication between the interior of the tubing string and a production zone of the formation. A ball can be inserted into a tubing string and moved along the tubing string by injected pressurized fracturing fluid until the ball sits on a valve seat of a valve sub-assembly coupled to the sliding piston to close off the tubing string below the valve. The force of the fluid forces the piston downwards to shear off the pins and open the ports. Fracturing fluid can then exit the ports to fracture the production zone of the formation.