Subsea Control Module With Hydraulic Accumulators for Autonomous Safety
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional subsea control systems for offshore oil and gas operations rely on surface-based hydraulic lines for pressure control, leading to reliability issues and unavailability of subsea equipment during initial pressurization, and are compromised by communication faults, lacking autonomous control capabilities.
Innovation Solution
A subsea control module with redundant electronics and dump valves, capable of independent operation and SIL3 certification, allows for safe isolation and pressure management without surface intervention, using hydraulic accumulators for quick repressurization and communication redundancy.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If surface-based hydraulic lines are used for pressure control, then subsea equipment can be controlled from the surface, but reliability decreases and equipment becomes unavailable during initial pressurization
Solution Approach 1:
The patent applies preliminary action by pre-pressurizing hydraulic accumulators at the subsea control module before operation begins. This allows the system to have immediate hydraulic availability without waiting for surface pressurization, eliminating the initial pressurization delay and improving reliability during critical startup phases.
Solution Approach 2:
The patent introduces hydraulic accumulators as intermediaries between the surface hydraulic system and subsea valves. These accumulators store pressurized hydraulic fluid locally, acting as a buffer that maintains system operation even when surface hydraulic lines are unavailable or undergoing pressurization, thereby improving reliability and reducing downtime.
2Extent of automation
If centralized surface control is used, then control logic can be centrally managed, but autonomous control capability is lost and communication faults compromise safety
Solution Approach 1:
The patent segments the control system into distributed subsea control modules that each possess independent processing capabilities. Each module can execute control logic locally without continuous surface communication, enabling autonomous operation while maintaining the ability to receive high-level commands from the surface when available. This segmentation provides fault tolerance and maintains safety during communication outages.
Solution Approach 2:
The subsea control modules are designed to be self-sufficient with onboard processors that can independently execute control algorithms and make safety decisions. The modules monitor their own hydraulic accumulators and can autonomously activate valves or initiate safety procedures without surface intervention, embodying the self-service principle to maintain operational independence and safety.
3Reliability
If hydraulic lines are depressurized for safety, then safety valves can be activated, but equipment becomes unavailable and downtime increases
Solution Approach 1:
The patent pre-pressurizes multiple hydraulic accumulators before safety events occur. When a safety activation is required, the system can immediately draw from these pre-charged accumulators to activate safety valves without depressurizing the entire hydraulic line. This preliminary preparation maintains equipment availability while ensuring safety functions can be executed instantly when needed.
Solution Approach 2:
The patent extracts the safety function from the main hydraulic line by providing dedicated hydraulic accumulators specifically for safety valve actuation. This separation allows safety operations to be performed independently without affecting the main production hydraulic system, enabling safety activations without causing widespread equipment shutdown and minimizing downtime.
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
Enables reliable and autonomous control of subsea equipment, maintaining safety and process functions even with communication loss, and reduces downtime by allowing instantaneous or delayed valve activation and rapid line repressurization.
Implementation Method 1
using hydraulic accumulators for quick repressurization
Data Source
AI summary
The present invention relates to a smart subsea control module for controlling subsea equipment independent of equipment located above the surface of the sea, and particularly for independently managing control and safety strategies according to a programmed logic.