Nested Guide Tube Assembly for Gas Turbine Inspection

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Visual inspection of internal components and fasteners within gas turbine engines is challenging due to confined spaces and complex pathways, making it difficult to access and inspect areas such as the compressor, combustion chamber, and turbine.

Innovation Solution

A multi-tube assembly comprising a rigid guide tube and a pre-shaped flexible guide tube, where the flexible guide tube is inserted through the rigid guide tube to navigate past interior components, allowing a tool, such as a borescope, to reach inaccessible areas by manipulating the flexible guide tube's shape and position.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Ease of operation

If a rigid inspection tool is used to inspect internal components, then the tool structure is simple and durable, but the tool cannot navigate complex pathways and confined spaces within the engine

Engineering Contradiction:

Improveability to navigate complex pathwaysVSAvoidtool structure complexity

Core Design Contradiction:

Ease of operationVSDevice complexity

Solution Approach 1:

The patent employs a nested tube structure where a flexible guide tube is inserted through a rigid guide tube. The rigid outer tube provides structural support and protection, while the flexible inner tube can bend and navigate complex pathways. This nested configuration allows the inspection tool to access confined spaces and follow complex engine internal pathways while maintaining structural integrity and durability through the rigid outer protection.

Inventive Principle:

Principle #7Nested doll (Nesting)

Solution Approach 2:

The patent utilizes a flexible guide tube with a pre-formed shape that can bend and conform to the complex internal geometry of the gas turbine engine. This flexible tube allows the inspection tool to navigate around obstacles and reach inaccessible areas within the engine, solving the problem of accessing confined spaces while maintaining a relatively simple overall tool structure.

Inventive Principle:

Principle #30Flexible shells and thin films

2Adaptability or versatility

If a flexible guide tube is used to navigate complex pathways, then the tool can reach inaccessible areas, but the tool becomes more complex and harder to control

Engineering Contradiction:

Improveability to reach inaccessible areasVSAvoidtool control difficulty

Core Design Contradiction:

Adaptability or versatilityVSEase of operation

Solution Approach 1:

The nested tube structure provides inherent control mechanisms where the rigid outer tube constrains and guides the flexible inner tube's movement. This configuration allows the flexible tube to reach inaccessible areas while the rigid tube maintains directional control and prevents excessive bending, thereby reducing operational complexity despite increased adaptability.

Inventive Principle:

Principle #7Nested doll (Nesting)

Solution Approach 2:

The flexible guide tube is pre-formed with a specific shape configuration that is predetermined to match the engine's internal pathway geometry. This pre-shaping reduces the complexity of real-time control during operation, as the tube's shape is already optimized for navigating the specific complex pathways it will encounter within the gas turbine engine.

Inventive Principle:

Principle #10Preliminary action

3Adaptability or versatility

If the tool is extended to reach remote areas, then inspection coverage is improved, but the tool is more vulnerable to damage

Engineering Contradiction:

Improveinspection coverageVSAvoidtool damage risk

Core Design Contradiction:

Adaptability or versatilityVSReliability

Solution Approach 1:

The rigid outer guide tube serves as a protective sheath for the flexible inner tube and the inspection tool. This nested configuration extends inspection coverage to remote areas while the rigid outer tube provides mechanical protection against damage from engine components, debris, and environmental factors, thereby maintaining tool reliability despite extended reach.

Inventive Principle:

Principle #7Nested doll (Nesting)

Solution Approach 2:

The flexible guide tube acts as a protective conduit that can absorb and distribute mechanical stresses encountered during navigation through complex pathways. Its flexibility allows it to conform to engine geometry without transmitting excessive forces to the inspection tool, reducing damage risk while maintaining extended reach capability.

Inventive Principle:

Principle #30Flexible shells and thin films

Data Source

PatentUS11913344B2Multi-tube servicing tool and method of servicing gas turbine engine components

Publication Date: 2024.02.27 GENERAL ELECTRIC CO

AI summary

A method of servicing a portion of a gas turbine engine includes inserting a rigid guide tube into an inspection port in a shroud of the gas turbine engine. The flexible guide tube is inserted into and through the rigid guide tube. The flexible guide tube is pre-shaped such that the flexible guide tube is biased towards a predetermined shape after being inserted through the rigid guide tube. A tool is pushed through the flexible guide tube such that the distal end of the tool moves out of and away from an end of the flexible guide tube. An area of interest of the gas turbine engine is then serviced with the tool.