Gas Turbine Combustor Joint with Melt-Break Flange

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

The existing sealing joints in industrial gas turbine engine combustors are prone to wear due to vibrations, making it difficult to refurbish or repair the channeled flanges, which reduces the longevity of the flow sleeve since these flanges are welded and hard to replace.

Innovation Solution

A joint design featuring a flange with a lower melting point bonding material that allows for easy replacement by melting the bond between the flange and the segments, enabling the removal and replacement of worn flanges with new ones, using a brazing process with a melting point below the segments' material, thus maintaining the integrity of the flow sleeve.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If a piston ring is used to seal the gap between flow sleeve and impingement sleeve, then sealing effectiveness is improved, but the flange becomes difficult to refurbish or repair when worn

Engineering Contradiction:

Improvesealing effectivenessVSAvoidflange refurbishment difficulty

Core Design Contradiction:

ReliabilityVSEase of repair

Solution Approach 1:

The joint is divided into separable components: a flange attached to the flow sleeve and a mating component on the impingement sleeve. The bonding material creates a detachable connection that allows the flange to be removed and replaced independently, solving the repair difficulty while maintaining sealing through the piston ring mechanism.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The bonding material's melting point is specifically selected to be lower than the base metal (flow sleeve and flange) but high enough to provide operational strength. This parameter differentiation enables selective melting of the bonding material for flange removal without damaging the permanent structural components, facilitating easy repair.

Inventive Principle:

Principle #35Parameter changes

2Strength

If the flange is welded to the flow sleeve for strong attachment, then joint strength is improved, but the flow sleeve longevity is reduced when the flange wears

Engineering Contradiction:

Improvejoint attachment strengthVSAvoidflow sleeve longevity

Core Design Contradiction:

StrengthVSDuration of action of stationary object

Solution Approach 1:

The joint system is segmented into a replaceable flange component and a permanent flow sleeve. The flange can be detached and replaced when worn, while the flow sleeve remains intact and reusable, thereby extending the overall system longevity without compromising joint strength during operation.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The flange is designed as a sacrificial, replaceable component with lower material cost compared to the flow sleeve. When the flange wears from piston ring contact, it can be removed and replaced without affecting the permanent flow sleeve, effectively extending system life at minimal cost.

Inventive Principle:

Principle #27Cheap short-living objects (Disposable)

3Ease of repair

If bonding material with lower melting point is used to attach the flange, then ease of flange replacement is improved, but bonding strength may be reduced

Engineering Contradiction:

Improveflange replacement easeVSAvoidbonding strength

Core Design Contradiction:

Ease of repairVSStrength

Solution Approach 1:

The bonding material's melting point is optimized to fall between the operational temperature requirements and the base metal melting point. This parameter selection ensures sufficient bonding strength during combustor operation while allowing controlled melting at moderate temperatures for flange removal and replacement.

Inventive Principle:

Principle #35Parameter changes

Solution Approach 2:

The joint assembly uses a composite material system combining the flange, bonding material, and flow sleeve with deliberately different thermal properties. The bonding material acts as a thermal weak link that melts at a lower temperature than the structural metals, enabling repair while maintaining structural integrity during normal operation.

Inventive Principle:

Principle #40Composite materials

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

This solution allows for the efficient replacement of worn flanges without damaging the flow sleeve, extending its longevity and minimizing downtime during maintenance, while maintaining the structural integrity of the combustor.

Implementation Method 1

A melting point of the bonding material is less than a melting point of the flange and a melting point of the segments

Methodology Applied

Scientific EffectMelting: Melting

Implementation Method 2

The flange may be brazed to a mounting portion of a first of the segments

Methodology Applied

Scientific EffectBrazing: Brazing

Data Source

PatentUS10830447B2Joint for sealing a gap between casing segments of an industrial gas turbine engine combustor

Publication Date: 2020.11.10 RTX CORP

AI summary

A casing for a combustor includes an upstream segment, a downstream segment and a joint. The downstream segment is constructed and arranged to move telescopically with respect to the upstream segment and along a centerline. The joint includes a flange and bonding material, which attaches the flange to the upstream segment or the downstream segment. A melting point of the bonding material is less than a melting point of the flange and/or a melting point of the segments.