Subsea Actuator Spring Release for Fail-Safe Valve Closure
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Subsea oil and gas operations rely on costly and complex umbilicals for hydraulic fluid supply, which can be expensive and prone to failures, necessitating a solution to reduce costs and complexity while maintaining fail-safe valve operation.
Innovation Solution
A subsea actuator design featuring a motor, biasing element, and holding element that allows for fail-safe operation by pre-tensioning a spring or polymer element to ensure valve closure upon loss of input force, eliminating the need for external hydraulic power and simplifying the umbilical system.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If hydraulic fluid supply through umbilical is used to operate subsea valves, then reliable fail-safe operation is achieved, but system complexity and cost increase significantly
Solution Approach 1:
The patent extracts the hydraulic power supply function from the umbilical system and relocates it to a local hydraulic power unit positioned near the subsea installation. This eliminates the need for expensive and complex umbilical hydraulic lines while maintaining reliable fail-safe valve operation through local hydraulic actuation.
Solution Approach 2:
The patent introduces a hydraulic power unit as an intermediary component between the control system and the valves. This intermediary generates and supplies hydraulic fluid locally, replacing the umbilical hydraulic supply and reducing system complexity while preserving fail-safe operation capabilities.
2Ease of operation
If umbilical is used for hydraulic fluid supply, then valve operation is controlled, but cost and installation complexity increase
Solution Approach 1:
The patent segments the control system into separate functional modules: a control module for valve operation and a local hydraulic power unit for fluid supply. This segmentation allows valve control to be maintained while eliminating the complex umbilical installation, as the hydraulic power unit operates independently near the subsea installation.
Solution Approach 2:
The local hydraulic power unit provides self-service by generating and supplying its own hydraulic fluid locally without requiring external umbilical supply. This enables autonomous operation of the hydraulic actuation system, simplifying installation while maintaining full valve control capability.
3Reliability
If external hydraulic power supply is used, then actuator operation is reliable, but system cost increases
Solution Approach 1:
The patent extracts the hydraulic power generation function from the external supply system and places it locally at the subsea installation. This eliminates the need for expensive external hydraulic power supply infrastructure while maintaining reliable actuator operation through local hydraulic power generation.
Solution Approach 2:
The local hydraulic power unit serves multiple functions: it provides hydraulic power for actuator operation, supplies fluid for fail-safe valve closure, and operates independently without external infrastructure. This multi-functionality maintains reliability while reducing system complexity and cost.
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 actuator design reduces costs by eliminating the need for umbilicals, ensures reliable fail-safe operation of subsea valves, and allows for standardized and adaptable control systems, enhancing operational efficiency and safety.
Implementation Method 1
a first biasing element; wherein the first biasing element and the stem are releasably connected via the force transmitting arrangement, such that when the first biasing element and the stem are released from each other, the first biasing element is configured to be pre-tensioned
Data Source
AI summary
The following invention relates to a subsea actuator (16′; 16″) for actuating a subsea rotating component (81; 181); comprising: a first biasing element (82; 182); a motor (85; 185); a holding element (83; 100, 183) configured to receive an input force; a rotatable stem (80′, 80″, 250, 84; 80; 200) operatively connectable to the component; a force transmitting arrangement (84, 80′, 80″; 83, 84; 183′, 195, 201; 84, 99, 86, 101, 83) connectable to the first biasing clement (82; 182) and the holding element (83; 100, 183); a first connection which in a first mode is configured to lock the stem (80′, 80″, 250, 84; 80; 200) in a rotatable engagement with the motor (85; 185) and in a second mode is configured to unlock the stem (80′, 80″, 250, 84; 80; 200) from the rotatable engagement with the motor (85; 185) and allow the stem (80′, 80″, 250, 84; 80; 200) to be influenced by the first biasing element (82; 182); wherein the first biasing element (82; 182) and the stem (80′, 80″, 250, 84; 80; 200) are releasably connected via the force transmitting arrangement (84, 80′, 80″; 83, 84; 183′, 195, 201; 84, 99, 86, 101, 83), such that when the first biasing element (82; 182) and the stem (80′, 80″, 250, 84; 80; 200) are released from each other, the first biasing element (82; 182) is configured to be pre-tensioned to a position representing a first pre-tensioned position of the actuator (16′; 16″) without operating the stem (80′, 80″, 250, 84; 80; 200); the holding element (83; 100, 183) is configured to exert a holding force on the force transmitting arrangement (84, 80′, 80″; 83, 84; 183′, 195, 201) and the first biasing element (82; 182) in the first pre-tensioned position; and wherein, when the first biasing element (82; 182) and the stem (80′, 80″, 250, 84; 80; 200) are connected and the first biasing element (82; 182) is pre-tensioned, the first connection is in the first mode such that the motor (85; 185) is configured to operate the stem (80′, 80″, 250, 84; 80; 200) to a position representing a second pre-tensioned position of the actuator (16′; 16″); wherein, in the second pre-tensioned position, upon loss of input force to the holding element (83; 100, 183), the holding element (83; 100, 183) is configured to release its holding force on the force transmitting arrangement (84, 80′, 80″; 83, 84; 183′, 195, 201; 84, 99, 86, 101, 83) and the first biasing element (82; 182), thereby the first connection is unlocked to its second mode, such that the pre-tensioned first biasing element (82; 182) is released and rotates the stent (80′, 80″, 250, 84; 80; 200) to a position representing a release position of the actuator (16′; 16″).