High-Temperature Optical Probe With Purge Rings for In-Situ Gas Monitoring

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Current gas monitoring apparatuses are complex, costly, and require multiple components, are limited to lower temperatures, and necessitate additional equipment for high-temperature applications, lacking field-replaceable parts and efficient, low-utility consumption solutions for monitoring process gases in harsh conditions.

Innovation Solution

A simple probe design with a removable probe body, featuring a measurement tube made of high-temperature resistant materials, purge gas assemblies, and a retroreflector assembly, allowing for in-situ monitoring without sample conditioning, capable of withstanding temperatures up to 1100°C and temperature fluctuations.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If current gas monitoring apparatuses are used, then measurement capability is provided, but device complexity increases and cost increases

Engineering Contradiction:
Improvemeasurement capabilityVSAvoidapparatus complexity
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The patent combines the measurement tube, optical components, and temperature-resistant structure into a single integrated probe assembly that can be inserted directly into the process stream. This eliminates the need for separate transmitters, receivers, and sample conditioning equipment, thereby reducing device complexity while maintaining measurement capability.

Inventive Principle:
Principle #5Merging (Combining)

Solution Approach 2:

The probe assembly serves multiple functions simultaneously: it provides optical measurement pathways for gas analysis, structural support for high-temperature environments, and direct in-situ monitoring capability. This multi-functionality reduces the number of separate components needed, addressing the complexity issue.

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

2Reliability

If current gas monitoring apparatuses are used, then measurement capability is provided, but cost increases

Engineering Contradiction:
Improvemeasurement capabilityVSAvoidcost
Core Design Contradiction:
ReliabilityVSEase of manufacture

Solution Approach 1:

The probe assembly is designed as a field-replaceable component with a simplified structure that can be manufactured more economically. By making the probe a discrete, replaceable unit rather than part of a complex permanent installation, the cost of manufacture and eventual replacement is reduced.

Inventive Principle:
Principle #27Cheap short-living objects (Disposable)

3Reliability

If current gas monitoring apparatuses are used, then measurement capability is provided, but additional equipment is required for high temperatures

Engineering Contradiction:
Improvemeasurement capabilityVSAvoidequipment requirements
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The measurement tube is constructed from materials specifically selected for their high-temperature resistance, allowing the probe to operate directly in hot process streams without auxiliary cooling equipment. This material parameter change enables the probe to withstand temperatures that would otherwise require complex cooling systems.

Inventive Principle:
Principle #35Parameter changes

4Temperature

If auxiliary cooling is implemented, then high temperature operation is enabled, but energy consumption increases and device complexity increases

Engineering Contradiction:
Improvehigh temperature operationVSAvoidenergy consumption
Core Design Contradiction:
TemperatureVSUse of energy by moving object

Solution Approach 1:

The measurement tube material parameters are changed to high-temperature resistant alloys or ceramics, fundamentally altering the thermal tolerance of the probe. This eliminates the need for auxiliary cooling systems, thereby reducing energy consumption and device complexity while enabling high-temperature operation.

Inventive Principle:
Principle #35Parameter changes

5Temperature

If auxiliary cooling is implemented, then high temperature operation is enabled, but device complexity increases

Engineering Contradiction:
Improvehigh temperature operationVSAvoidequipment requirements
Core Design Contradiction:
TemperatureVSDevice complexity

Solution Approach 1:

By changing the material parameters of the measurement tube to high-temperature resistant materials, the probe can operate directly in high-temperature environments without auxiliary cooling equipment, thereby reducing device complexity while enabling high-temperature operation.

Inventive Principle:
Principle #35Parameter changes

6Ease of repair

If field-replaceable components are implemented, then maintenance efficiency is improved, but device complexity increases

Engineering Contradiction:
Improvemaintenance efficiencyVSAvoidcomponent structure
Core Design Contradiction:
Ease of repairVSDevice complexity

Solution Approach 1:

The probe assembly is segmented into a field-replaceable measurement tube component and a permanent transmitter housing. This segmentation allows the measurement tube to be replaced in the field without replacing the entire analyzer, improving maintenance efficiency while adding minimal structural complexity through the use of standardized connection interfaces.

Inventive Principle:
Principle #1Segmentation

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, low-cost, and efficient monitoring of process gases with information-rich data, allowing for continuous operation and reduced downtime, while minimizing utility consumption and maintaining mechanical integrity under extreme conditions.

Implementation Method 1

a retroreflector assembly that includes a retroreflector having two or more reflector walls adapted to redirect light emitted from a light source

Methodology Applied
Scientific EffectRetroreflection: Retroreflector

Implementation Method 2

The measurement tube is formed of a material that is resistant to sag when exposed to high temperatures up to and including 1100°C

Methodology Applied
Scientific EffectThermal resistance: Thermal Insulation

Implementation Method 3

The purge gas outlet openings are, according to the claimed invention, angled such that the purge gas is adapted to swirl about a surface of the process window

Methodology Applied
Scientific EffectSwirling flow: Vortex Ring

Data Source

PatentEP3906405B1High-temperature optical probe
Publication Date: 2026.01.14 DOW GLOBAL TECHNOLOGIES LLC
  • EP3906405B1 patent drawingFigure 1
  • EP3906405B1 patent drawingFigure 2~3B
  • EP3906405B1 patent drawingFigure 4~5

AI summary

A probe body (12) in a optical probe (10) including a measurement tube (14) having a plurality of probe vents (16) adapted to allow process fluid to flow there through; two or more purge rings, each including a process window, a purge gas inlet, and a plurality of purge gas outlet openings adapted to direct purge gas toward or adjacent to the process window; and a measurement region defined by a portion of the measurement tube and two or more of the purge rings.