Optical Feedthrough for Subsea Christmas Tree Monitoring

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Conventional subsea Christmas trees lack comprehensive condition monitoring capabilities, leading to uncertainties in production process optimization and impending failure prediction due to limited sensor data and potential sensor inaccuracies.

Innovation Solution

A method and system utilizing an optical feedthrough module to communicate optical signals with optical sensors within the Christmas tree assembly, enabling the determination of health metrics and identification of problem conditions through a condition monitoring unit.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If conventional sensors are used in Christmas tree assemblies, then the system structure remains simple, but measurement precision and reliability of condition monitoring deteriorate due to sensor failures and inaccuracies

Engineering Contradiction:
Improvesensor accuracyVSAvoidsystem structure
Core Design Contradiction:
Measurement precisionVSDevice complexity

Solution Approach 1:

The patent replaces conventional electrical sensors with optical sensors that use light-based measurement principles. Optical sensors measure physical quantities such as pressure, temperature, and displacement by detecting changes in optical properties (refractive index, light absorption, interference patterns) rather than using electrical signals, thereby eliminating electrical interference and improving measurement precision while maintaining structural simplicity

Inventive Principle:
Principle #28Mechanics substitution (Replace mechanical system)

Solution Approach 2:

The patent changes the operating parameter domain from electrical to optical by using light wavelength, intensity, or phase as the measurement parameter. This parameter change enables sensors to operate in environments with electrical interference and provides immunity to electromagnetic noise, thereby improving reliability without significantly increasing system complexity

Inventive Principle:
Principle #35Parameter changes

2Reliability

If comprehensive sensor monitoring is implemented, then reliability of condition monitoring improves, but device complexity increases due to additional sensors and data processing requirements

Engineering Contradiction:
Improvecondition monitoring reliabilityVSAvoidsensor network complexity
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The patent employs optical sensors that can simultaneously measure multiple parameters (pressure, temperature, displacement, vibration) using a single integrated optical platform. The optical detection system processes different physical quantities through a unified optical pathway and signal processing architecture, enabling comprehensive monitoring while reducing the number of separate sensor systems required

Inventive Principle:
Principle #6Universality (Multi-functionality)

Solution Approach 2:

The patent introduces an optical interface or transducer as an intermediary that converts various physical parameters into optical signals for unified processing. This intermediary optical system acts as a common language converter, allowing different measurement types to be transmitted and processed through a single optical communication channel, thereby reducing data processing complexity while maintaining comprehensive monitoring capability

Inventive Principle:
Principle #24Intermediary (Mediator)

3Measurement precision

If optical sensors are used within pressure boundary, then measurement precision improves, but device complexity increases due to optical feedthrough requirements

Engineering Contradiction:
Improveparameter measurement accuracyVSAvoidoptical feedthrough module
Core Design Contradiction:
Measurement precisionVSDevice complexity

Solution Approach 1:

The patent employs thin optical windows or membranes made of transparent materials (such as sapphire, quartz, or specialized polymers) that seal the pressure boundary while allowing optical signals to pass through. These thin film structures maintain pressure containment integrity while being optically transparent across the required wavelength range, enabling sensor placement inside the pressure boundary without complex feedthrough mechanisms

Inventive Principle:
Principle #30Flexible shells and thin films

Solution Approach 2:

The patent uses optical coupling methods where the actual physical quantity inside the pressure boundary is copied or replicated as an optical signal that can be transmitted through the boundary. Rather than physically passing electrical connections through the pressure boundary, the system creates an optical copy of the measurement data that can be transmitted through transparent barriers, simplifying the interface between pressurized and unpressurized zones

Inventive Principle:
Principle #26Copying

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

Enhances the monitoring of subsea hydrocarbon production by providing accurate health metrics and predictive maintenance, optimizing operations and extending component lifespan.

Implementation Method 1

an optical feedthrough module operable to communicate through a pressure boundary of the Christmas tree assembly at least one optical signal with a plurality of optical sensors

Methodology Applied
Scientific EffectOptical signal transmission: Light

Data Source

PatentEP2329101B1Optical sensing system for wellhead equipment
Publication Date: 2018.06.13 FMC TECHNOLOGIES INC
  • EP2329101B1 patent drawingFigure 1
  • EP2329101B1 patent drawingFigure 2
  • EP2329101B1 patent drawingFigure 3

AI summary

A system includes a Christmas tree assembly mounted to a hydrocarbon well, an optical feedthrough module, and a plurality of optical sensors. The optical feedthrough module is operable to communicate through a pressure boundary of the Christmas tree assembly. The plurality of optical sensors is disposed within the Christmas tree assembly for measuring parameters associated with the Christmas tree assembly and is operable to communicate through the optical feedthrough module.