In-situ Rotor Blade Grinding with Dust Extraction

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Setting a predetermined radial gap width for rotor blades in turbomachines is challenging due to varying production tolerances and other influencing factors, leading to difficulties in maintaining original performance and requiring inaccurate machining methods that risk contaminating the turbomachine with grinding dust.

Innovation Solution

A method involving partial removal of the housing to expose rotor blades, using a grinding device with a screening device and suction extraction to prevent dust contamination, allowing for in-situ machining with high accuracy without disassembling the rotor, ensuring precise radial gap width setting and optimizing turbomachine performance.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Manufacturing precision

If rotor blades are machined in situ using a grinding device, then machining accuracy is improved and original performance is maintained, but grinding dust will contaminate the turbomachine

Engineering Contradiction:

Improvemachining accuracyVSAvoidgrinding dust contamination

Core Design Contradiction:

Manufacturing precisionVSObject-affected harmful factors

Solution Approach 1:

A removable housing part is introduced as an intermediary element that is detached to provide access for the grinding device, then reattached to contain grinding dust. This mediator allows the grinding operation to proceed with high accuracy while preventing dust contamination of the turbomachine interior.

Inventive Principle:

Principle #24Intermediary (Mediator)

Solution Approach 2:

The housing part is extracted or removed from the turbomachine assembly to create an open access path for the grinding device. This extraction allows the grinding operation to be performed on the rotor blades while the removed housing part prevents dust from spreading into the turbomachine.

Inventive Principle:

Principle #2Taking out (Extraction)

2Ease of manufacture

If the rotor is unstacked to machine blades with a conventional grinding system, then machining can be performed, but considerable effort and time are required

Engineering Contradiction:

Improvemachining accessibilityVSAvoiddisassembly time

Core Design Contradiction:

Ease of manufactureVSLoss of time

Solution Approach 1:

The housing is segmented into removable parts that can be detached to expose the rotor blades for machining. This segmentation allows the grinding device to access the blades without requiring complete disassembly of the rotor stack, significantly reducing preparation time while maintaining machining accessibility.

Inventive Principle:

Principle #1Segmentation

3Loss of time

If a dummy rotor disk is used instead of the original rotor disk, then the rotor need not be unstacked, but machining accuracy decreases

Engineering Contradiction:

Improvedisassembly timeVSAvoidmachining accuracy

Core Design Contradiction:

Loss of timeVSManufacturing precision

Solution Approach 1:

The removable housing part acts as a mediator that provides access to the rotor blades while the original rotor disk remains in place. This approach combines the advantages of not unstacking the rotor with maintaining high machining accuracy, as the original rotor disk's precise geometry is preserved during the grinding operation.

Inventive Principle:

Principle #24Intermediary (Mediator)

4Ease of operation

If blades are machined without a rotor disk using a single blade grinding apparatus, then machining can be performed, but machining accuracy is reduced

Engineering Contradiction:

Improvemachining simplicityVSAvoidmachining accuracy

Core Design Contradiction:

Ease of operationVSManufacturing precision

Solution Approach 1:

The grinding device is designed with multi-functionality, capable of operating with the rotor disk in place while providing access to individual blades through the removable housing part. This universal design maintains machining accuracy by preserving the rotor disk's structural support while enabling straightforward operation on mounted blades.

Inventive Principle:

Principle #6Universality (Multi-functionality)

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 method achieves superior machining accuracy and optimizes turbomachine performance by preventing dust contamination and eliminating the need for rotor disassembly, resulting in time and cost savings while maintaining original performance.

Implementation Method 1

providing a suction extraction such that it extracts grinding dust from the screened-off machining region

Methodology Applied

Scientific EffectSuction: Suction

Data Source

PatentUS9969055B2Method and device for setting a predetermined radial gap width for rotor blades of a turbomachine

Publication Date: 2018.05.15 SIEMENS ENERGY GLOBAL GMBH & CO KG

AI summary

A method and device for setting a predetermined radial gap width for rotor blades arranged in a housing of a turbomachine is provided. The method includes removing a housing part and at least partially exposing the rotor blades which are to be machined, arranging a grinding device in the region of a rotor blade which is to be machined such that the tip of the rotor blade is machined using a grinding disk of the grinding device, screening off the machining region by arranging a screening device which is formed so as to counter a release of grinding dust from the screen off machining region, providing a suction extraction such that it extracts grinding dust from the screened-off machining region and grinding the tip of the rotor blade in situ producing the radial gap width.