Electric Subsurface Safety Valve Using Annulus Pressure Actuation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing surface-controlled subsurface safety valves (SCSSVs) face challenges such as limited tool sizes, high costs, reliability issues due to harsh environments, and the need for hydraulic fluids, which are problematic in deepwater and corrosive offshore hydrocarbon production wells.
Innovation Solution
The development of an electrically surface-controlled subsurface safety valve (ESCSSV) that uses well pressure to actuate a moveable piston structure without hydraulic control lines, featuring a simpler design with optional electromagnet redundancy, thinner tool walls, and lower operating temperatures, allowing for fail-safe operation by closing automatically in case of electrical disconnection.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If hydraulic control lines are used to actuate the safety valve, then the valve can be controlled from surface, but the system becomes complex and unreliable in harsh environments
Solution Approach 1:
The patent removes hydraulic control lines and associated hydraulic fluid from the system, extracting the problematic components that caused reliability issues and complexity. The valve is actuated directly by well pressure acting on a piston, eliminating the need for external hydraulic control infrastructure.
Solution Approach 2:
The safety valve uses well pressure itself to actuate the valve mechanism through a piston, making the system self-service. The pressure already present in the wellbore is utilized to control the valve without requiring separate hydraulic control lines or external fluid systems.
2Reliability
If the safety valve is set deep in the production well (1,000 feet or more), then it can protect against production mishaps, but the tool wall thickness and operating temperature requirements increase
Solution Approach 1:
The patent changes the operating parameters of the valve by designing it to function at lower temperatures and with thinner wall thicknesses. The electric actuation mechanism and pressure-operated piston allow the valve to be set deeper in the well where temperature and pressure conditions are more extreme, while maintaining reliability through simplified construction.
3Ease of operation
If hydraulic fluids are used for valve actuation, then surface control is achieved, but the system becomes problematic in deepwater and corrosive environments
Solution Approach 1:
The patent replaces the hydraulic fluid-based mechanical control system with an electric actuation system. An electric motor or electromagnet positioned at the surface can send electrical signals downhole to actuate the valve, eliminating the need for hydraulic fluids that are problematic in deepwater and corrosive environments.
Solution Approach 2:
The patent introduces an electrical signal as an intermediary between surface control and downhole valve actuation. Instead of directly transmitting hydraulic pressure from surface to downhole, electrical signals serve as the mediator that triggers the downhole piston mechanism, allowing control without physical hydraulic connections.
4Ease of operation
If a complex hydraulic control system is used, then valve actuation is achieved, but the cost and manufacturing complexity increase
Solution Approach 1:
The patent segments the valve actuation function into two independent parts: an electric actuation mechanism at the surface and a simple pressure-operated piston at the downhole valve. This segmentation allows each component to be manufactured separately using simpler, less expensive processes, eliminating the need for complex integrated hydraulic control systems.
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 ESCSSV provides increased reliability and safety by eliminating hydraulic control lines, ensuring the valve remains closed in case of damage, and can operate at virtually unlimited water depths with reduced costs and complexity, maintaining wellbore fluid containment.
Implementation Method 1
differential pressure across a piston to move the bore flow management actuator between a flow state and a closed state
Implementation Method 2
an electromagnet assembly configured to hold the bore flow management actuator in the flow state
Data Source
AI summary
Provided is an electrically surface-controlled subsurface safety valve (ESCSSV). The ESCSSV, in one example, includes an outer housing comprising a central bore extending axially through the housing that is configured to convey production fluids there through. The ESCSSV, in this embodiment, further includes a valve closure mechanism disposed proximate a downhole end of the central bore, and a bore flow management actuator disposed in the central bore and configured to move between a closed state and a flow state to engage or disengage the valve closure mechanism to determine a flow condition of the production fluids through the central bore. The ESCSSV, in this embodiment, additionally includes an electric valve assembly fluidically coupled to the bore flow management actuator and configured to select between a section pressure or the annulus pressure to control the bore flow management actuator and determine the flow condition of production fluids through the central bore.