Spring-Loaded Equalization Valve for Subsea Cap Pressure Management
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Hydraulically-actuated valves used in subsea hydrocarbon drilling operations for pressure equalization are complex, large in form factor, and complicate the coupling process due to high pressure differentials, making them difficult to maneuver and increasing the distance required for connector placement, which complicates 'wet parking' and requires excessive force for actuation.
Innovation Solution
A high-pressure cap with an equalization valve that includes a sleeve and valve body with retention pins, a valve spring, and o-rings, allowing pressure equalization without displacing fluid when opening, reducing the force required and enabling a smaller form factor, allowing the valve to be positioned closer to the hub, facilitating easier coupling and reduced height of the cap.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a hydraulically-actuated valve is used for pressure equalization, then the valve can effectively equalize pressure across the high-pressure cap, but the valve becomes complex and large in form factor, making it difficult to maneuver the running tool and complicating connector placement
Solution Approach 1:
The patent replaces the complex hydraulically-actuated valve system with a simple mechanical spring-loaded poppet valve. The spring-loaded mechanism uses elastic potential energy stored in the valve spring to overcome the pressure differential, eliminating the need for hydraulic actuation systems. This substitution dramatically reduces the valve's form factor and complexity while maintaining pressure equalization functionality.
Solution Approach 2:
The patent changes the actuation mechanism from hydraulic pressure-driven to spring-force-driven. The valve spring is pre-compressed to store mechanical energy, and when the running tool actuates the valve, this stored energy is released to move the poppet and equalize pressure. This parameter change from hydraulic to mechanical energy storage simplifies the system architecture.
2Reliability
If a hydraulically-actuated valve is used, then pressure equalization can be achieved, but the valve height increases, requiring connectors to be placed at a greater distance from the hub, which complicates wet parking
Solution Approach 1:
The spring-loaded mechanical valve eliminates the need for extensive hydraulic piping and actuation mechanisms that would increase the cap's height. The compact spring and poppet assembly fit within a much smaller envelope, reducing the overall height of the high-pressure cap and allowing connectors to be placed closer to the hub, thereby facilitating wet parking operations.
3Reliability
If a hydraulically-actuated valve is used, then pressure equalization can be achieved, but a large amount of force is required to displace seawater and move the valve from closed to open position
Solution Approach 1:
The valve spring is pre-compressed during valve assembly to store elastic potential energy. This beforehand cushioning of spring force is designed to exactly counterbalance the maximum pressure differential that may occur during operation. When the running tool actuates the valve, this pre-stored spring energy is released to move the poppet, requiring minimal additional force from the running tool and eliminating the need to displacet large volumes of seawater.
Solution Approach 2:
The patent replaces the hydraulic force system with a spring-based mechanical force system. The spring's elastic properties provide the necessary actuation force, which is more efficient than hydraulic systems in this application because it directly converts stored mechanical energy into valve movement without requiring the displacement of large volumes of fluid.
4Reliability
If the high-pressure cap is designed with a large form factor valve, then pressure containment and relief can be achieved, but the overall cap height increases and complicates the coupling process
Solution Approach 1:
The compact spring-loaded poppet valve design maintains full pressure containment and relief functionality while occupying minimal space within the cap. The spring mechanism provides reliable pressure equalization without requiring the extensive internal volume needed for hydraulic systems, thereby maintaining a compact cap height that facilitates the coupling process.
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 minimizes the form factor and force needed to open the equalization valve, allowing for closer connector placement and easier maneuvering, reducing the overall height of the high-pressure cap and simplifying the coupling process while maintaining a pressure-tight seal.
Implementation Method 1
the valve includes a spring-loaded poppet wherein the spring-loaded poppet includes a spring and a poppet, and the spring biases the poppet from an initial closed position to an open position
Data Source
AI summary
A cap for protecting a sealing surface of a hub of a subsea device includes an equalization valve and a fluid conduit. The equalization valve includes a valve body having a pressure equalization conduit, a sleeve disposed about the valve body and having a port allowing fluid communication across the sleeve, and a valve spring configured to bias the sleeve to a closed position. The sleeve is configured to move to an open position in response to a force that depresses the sleeve and causes the valve spring to compress and the port is fluidly isolated from the pressure equalization conduit in the closed position and is in fluid communication with the pressure equalization conduit in the open position. In the open position, an interior environment of the subsea device is in fluid communication with the environment outside the cap through the equalization valve.