Gas Turbine Airfoil Tip Abrasive Coating Restoration

Solution Overview

Problem

Current maintenance methods for gas turbine engine airfoil tips with abrasive coatings are time-consuming and costly, requiring complete remanufacturing and welding, which is inefficient and prone to substrate damage.

Innovation Solution

A method involving surface treatment and electroplating of a supplemental abrasive coating onto the existing residual coating and substrate, allowing for restoration of airfoil tips to nominal height without complete removal and welding, reducing maintenance time and cost.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Manufacturing precision

If complete remanufacturing and welding is performed to restore airfoil tips, then the airfoil tip can be restored to nominal height, but maintenance time and cost increase significantly

Engineering Contradiction:

Improveairfoil tip height restorationVSAvoidmaintenance time

Core Design Contradiction:

Manufacturing precisionVSLoss of time

Solution Approach 1:

The invention extracts only the worn abrasive coating layer from the airfoil tip, rather than removing the entire airfoil tip or performing complete remanufacturing. This selective removal allows restoration of the abrasive coating while preserving the substrate, significantly reducing maintenance time and cost.

Inventive Principle:

Principle #2Taking out (Extraction)

Solution Approach 2:

The invention applies restoration treatment only to the specific region where the abrasive coating is worn (the tip region), rather than treating the entire airfoil. This localized approach maintains manufacturing precision for the critical tip height while minimizing overall maintenance time.

Inventive Principle:

Principle #3Local quality

2Manufacturing precision

If complete remanufacturing and welding is performed to restore airfoil tips, then the airfoil tip can be restored to nominal height, but cost increases significantly

Engineering Contradiction:

Improveairfoil tip height restorationVSAvoidmaintenance cost

Core Design Contradiction:

Manufacturing precisionVSEase of manufacture

Solution Approach 1:

The invention extracts only the worn abrasive coating layer from the airfoil tip, rather than removing the entire airfoil tip or performing complete remanufacturing. This selective removal allows restoration of the abrasive coating while preserving the substrate, significantly reducing maintenance time and cost.

Inventive Principle:

Principle #2Taking out (Extraction)

Solution Approach 2:

The invention treats the abrasive coating as a replaceable, consumable layer that can be restored independently of the expensive airfoil substrate. By focusing restoration efforts only on the abrasive coating layer rather than the entire airfoil structure, maintenance cost is significantly reduced.

Inventive Principle:

Principle #27Cheap short-living objects (Disposable)

3Manufacturing precision

If complete remanufacturing and welding is performed to restore airfoil tips, then the airfoil tip can be restored to nominal height, but substrate damage occurs

Engineering Contradiction:

Improveairfoil tip height restorationVSAvoidsubstrate integrity

Core Design Contradiction:

Manufacturing precisionVSStrength

Solution Approach 1:

The invention extracts only the worn abrasive coating layer from the airfoil tip, rather than removing the entire airfoil tip or performing complete remanufacturing. This selective removal allows restoration of the abrasive coating while preserving the substrate, significantly reducing maintenance time and cost.

Inventive Principle:

Principle #2Taking out (Extraction)

Solution Approach 2:

The invention replaces the mechanical welding process with a coating application process. Instead of using welding to restore the airfoil tip height, the invention applies a new abrasive coating layer over the prepared substrate, eliminating the risk of substrate damage associated with welding while achieving the same restoration goal.

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

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 approach reduces maintenance time and cost by allowing selective repair of airfoil tips, maintaining performance equivalent to original equipment standards, and minimizing substrate damage, thus extending part life and improving operational efficiency.

Implementation Method 1

applying a supplemental abrasive coating to the ground residual abrasive coating and the ground airfoil substrate adjacent the ground residual abrasive coating by electroplating the supplemental abrasive coating to the ground residual abrasive coating and to the ground airfoil substrate adjacent the residual abrasive coating

Methodology Applied

Scientific EffectElectroplating: Electroplating

Data Source

PatentEP2540961B1Abrasive airfoil tip

Publication Date: 2020.01.22 UNITED TECH CORP

Figure 1
Figure 2A~2B
Figure 3A~3C

AI summary

An airfoil (32) comprises a substrate (54), a residual abrasive coating (58) and a supplemental abrasive coating (62). The substrate extends along a tip section (51) of the airfoil, from a leading edge (48) to a trailing edge (50). The residual abrasive coating (58) comprises a two-phase abrasive and metal matrix material bonded to the substrate, on the tip section of the airfoil. The supplemental abrasive coating (62) comprises a two-phase abrasive and metal matrix material bonded to the residual abrasive coating and to the substrate adjacent the residual abrasive coating, on the tip section (51) of the airfoil. The supplemental abrasive coating restores the airfoil to a nominal tip height (57) in the tip section.