Subsea Valve Actuator Visual Indicator Pressure Compensation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Subsea valve actuators with manual override and visual position indicators have complex mechanical structures that risk seawater ingress and pressure differential issues, requiring multiple penetrations into the actuator housing.
Innovation Solution
A subsea valve actuator design with a visual valve position indicator externally mounted on the override shaft, enclosed in a fluid-filled, pressure-compensated indicator mounting enclosure, reducing mechanical complexity and eliminating the need for additional housing penetrations, using a carrier in rotary-to-linear motion conversion engagement with the override shaft for fluid communication and pressure compensation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If a separate indicator shaft with pinion and reduction gears is used to achieve visual position indication, then the valve position can be monitored remotely, but the mechanical structure becomes complex and synchronization between valve movement and indicator reading becomes difficult
Solution Approach 1:
The patent combines the indicator shaft with the override shaft into a single shared shaft. The visual indicator is mounted directly on this shaft, eliminating the need for separate pinion and reduction gear mechanisms. This merging of functions reduces mechanical complexity while maintaining accurate position indication, as the indicator moves directly with the shaft that also controls the valve.
Solution Approach 2:
The patent extracts the unnecessary intermediate transmission components (pinion and reduction gears) from the system. By directly mounting the visual indicator on the override shaft, the design removes complex mechanical transmission elements while preserving the essential function of position indication, thereby simplifying the overall mechanical structure.
2Ease of operation
If multiple penetrations into the actuator housing are made for override shaft and indicator shaft, then manual override and visual indication are achieved, but the risk of seawater ingress and pressure differential issues increases
Solution Approach 1:
The patent merges the override shaft and indicator shaft into a single shared shaft that passes through the actuator housing only once. This eliminates the need for separate penetrations for each function, reducing the number of sealing points and thereby improving reliability by minimizing opportunities for seawater ingress and pressure differential problems.
Solution Approach 2:
The single shared shaft serves multiple functions: it enables manual override of the valve and simultaneously provides the rotational movement for the visual position indicator. This multi-functionality allows both manual operation and visual indication to be achieved through a single penetration point, enhancing seawater protection and pressure integrity.
3Device complexity
If the indicator is mounted externally on the override shaft without pressure compensation, then the structure is simpler, but the indicator is exposed to seawater and pressure differentials affecting operation
Solution Approach 1:
The patent nests the visual indicator mounting within a pressure-compensated enclosure that is itself nested within the actuator housing structure. The indicator shaft passes through this enclosure, which is filled with pressure-compensating fluid. This nested arrangement protects the indicator mounting from seawater and pressure differentials while maintaining a relatively simple overall structure.
Solution Approach 2:
The patent introduces a pressure-compensated fluid enclosure as an intermediary between the external environment and the indicator mounting. This intermediary enclosure, filled with pressure-compensating fluid, mediates the exposure to pressure differentials and prevents seawater ingress to the indicator components, ensuring reliable operation without significantly increasing structural complexity.
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 provides a reliable, non-complex mechanical structure that protects the indicator from seawater and pressure differentials, ensuring accurate valve position monitoring and manipulation without additional housing penetrations, enhancing operational reliability and accessibility in subsea environments.
Implementation Method 1
enclosed in a fluid-filled, pressure-compensated indicator mounting enclosure
Implementation Method 2
using a carrier in rotary-to-linear motion conversion engagement with the override shaft
Data Source
AI summary
A subsea valve actuator is disclosed, comprising an override shaft (6) reaching from inside a fluid filled and pressure compensated actuator housing (1) to the exterior thereof via a bearing and sealing arrangement (7), wherein a visual valve position indicator (14) is arranged exterior to the actuator housing. The visual indicator (14) is pivotally mounted to the override shaft and guided non-rotatably to be forced in axial displacement on the override shaft when the override shaft is rotated, wherein the mounting of the visual indicator (14) on the override shaft (6) is encased in a fluid filled, pressure compensated indicator mounting enclosure (19) surrounding the override shaft (6) in sealing (26) relation outside of the actuator housing (1).