Downhole Stinger Actuation for Leak-Resistant Safety Valve Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing methods for delivering hydraulic control to downhole tools through tubing strings face issues with hydraulic pressure leakage and improper sealing, especially when a control line is damaged or cannot be run outside the tubing, necessitating a new control line to be run down the tubing string.
Innovation Solution
A stinger system is used that allows for the actuation of downhole tools using pressure communicated via control lines, where the stinger is removably disposed in the tubing and includes a stinger with a body and a piston, which is movable in response to pressure differentials, mechanically operating the tool without the need for hydraulic seals.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a control line is run outside the tubing string, then hydraulic control can be delivered to downhole tools, but the control line may become damaged or inoperable
Solution Approach 1:
The control line is nested inside the tubing string rather than running outside it. The stinger assembly with control line is deployed through the tubing string to the downhole tool, protecting the control line from external damage while maintaining hydraulic control capability.
2Adaptability or versatility
If a new control line is run down the tubing string, then a new surface-controlled subsurface safety valve can be controlled, but the system complexity increases
Solution Approach 1:
The control system is segmented into a reusable downhole tool and a disposable/replaceable stinger assembly. The stinger containing the control line can be independently deployed and retrieved, simplifying the process of replacing or upgrading control lines without affecting the main downhole tool.
Solution Approach 2:
The stinger acts as an intermediary component between the control line and the downhole tool. It provides a standardized interface that simplifies connection and disconnection, reducing overall system complexity while enabling flexible control line management.
3Reliability
If hydraulic seals are used to prevent leakage, then sealing can be achieved, but leakage and sealing issues still occur
Solution Approach 1:
The hydraulic seal interface is extracted and relocated to the stinger-tool connection point rather than requiring seals along the control line path. This concentrates the sealing requirement to a single, easily accessible interface, improving reliability and reducing leakage risks.
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 system effectively controls downhole tools by reducing the need for hydraulic seals, minimizing leakage, and allowing operation at greater depths with reduced complexity and component length, while being insensitive to hydrostatic pressures.
Implementation Method 1
The actuator has a second key disposed on the stinger. The second key is movable with the actuator between first and second positions. The second key is configured to engage the first key of the tool and is configured to move the operator at least from the first state to the second state.
Data Source
Figure 1A
Figure 1B
Figure 2
AI summary
A system used downhole in tubing is operable with pressure communicated via at least one control line. The system includes a tool and a stinger. The tool disposed with the tubing has a tool bore for passage of tubing flow. The tool has an operator movable between operable states, and the operator has a tool key disposed in the bore. The stinger removably disposed in the tubing is configured to insert into the tool bore. The stinger has an actuator in communication with the at least one control line. Actuated by the control line, a stinger key disposed on the stinger is movable with the actuator between positions. In this way, the stinger key is configured to engage the tool key and is configured to move the tool's operator at least from the one state to another.