Actuator Assist Apparatus for Subsea Depth Compensation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional hydraulic accumulator systems experience efficiency loss in subsea environments due to increased external hydrostatic pressure, leading to a reduced ratio between working pressure and minimum operating pressure, necessitating increased accumulator capacity and space requirements, which becomes unmanageable at depths of 2000 meters or greater.
Innovation Solution
An actuator assist apparatus with a housing and a piston member, featuring a force application arrangement that stores and releases energy to assist the actuator in extending, thereby increasing the working pressure ratio, reducing the required supply pressure, and decreasing the minimum operating pressure below hydrostatic pressure, thus reducing the need for accumulator capacity and space.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If accumulator capacity is increased to maintain operation at greater depths, then reliability is improved, but volume and weight increase significantly
Solution Approach 1:
The system is divided into two functional parts: the actuator for normal operation and the actuator assist apparatus for depth compensation. This segmentation allows the accumulators to be reduced in size while maintaining overall system reliability through the combined action of both components.
Solution Approach 2:
The actuator assist apparatus acts as an intermediary device between the reduced-capacity accumulators and the actuator. It receives hydraulic fluid from the accumulators and amplifies the available pressure through its piston mechanism, providing the necessary force assistance without requiring large accumulator volumes.
2Reliability
If accumulator capacity is increased to provide required operation and safety factors, then reliability is improved, but device complexity increases
Solution Approach 1:
The actuator assist apparatus serves multiple functions: it amplifies pressure, provides force assistance during actuator operation, and maintains reliability safety factors. This multi-functionality consolidates what would otherwise require multiple separate systems into a single integrated device.
3Power
If supply pressure is increased to maintain working pressure ratio, then actuator performance is improved, but loss of energy increases
Solution Approach 1:
The actuator assist apparatus operates periodically, engaging when pressure assistance is needed and disengaging when normal actuator operation suffices. This periodic engagement reduces continuous energy loss while maintaining actuator performance when required.
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 assist apparatus reduces the quantity of accumulators needed, minimizing space, weight, and operational costs, while ensuring efficient and reliable operation in subsea or downhole environments by lowering the minimum operating pressure and reducing lifting equipment requirements.
Implementation Method 1
The actuator assist apparatus may comprise a spring arranged to apply a force which assists in urging the actuator to the extended configuration
Implementation Method 2
fluid pressure in the first fluid chamber may urge the actuator assist apparatus towards the first, primed, configuration
Data Source
AI summary
An actuator assist apparatus for use with an actuator has a housing and a piston member slidably disposed in the housing. The piston member divides the interior of the housing into a first fluid chamber and a second fluid chamber. The actuator assist apparatus is configurable between a first, primed, configuration and an activated configuration. A force applicator is configured to store energy when the apparatus is in the primed configuration and release the energy to move the piston member relative to the housing. Movement of the piston member applies a force which assists in urging the actuator towards an extended configuration, thereby reducing the minimum operating pressure of the actuator.