Inlet Guide Vane Orientation Features for Compressor Assembly

Solution Overview

Problem

Improper installation of inlet guide vanes (IGVs) in gas turbine engines can lead to performance and structural issues, potentially resulting in costly compressor failures.

Innovation Solution

Incorporating a gear with a flat surface and an orientation pin, along with a cylindrical spindle featuring a flat surface, and a shaped boss on the IGV stem, to ensure proper orientation of the IGV during assembly, preventing backwards installation.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Ease of manufacture

If the IGV is installed without orientation features, then the assembly process is simpler, but the IGV may be installed in the wrong orientation causing performance issues and structural damage

Engineering Contradiction:

Improveassembly simplicityVSAvoidcorrect installation orientation

Core Design Contradiction:

Ease of manufactureVSReliability

Solution Approach 1:

The gear is designed with an asymmetric flat surface instead of a symmetric circular shape, and the spindle has a corresponding asymmetric flat surface. This asymmetry creates a unique orientation where only one configuration allows the flat surfaces to align and engage the orientation pin, physically preventing incorrect installation while maintaining simple assembly procedures.

Inventive Principle:

Principle #4Asymmetry

Solution Approach 2:

The orientation pin acts as an intermediary element that mediates between the gear's flat surface and the spindle's flat surface. This pin protruding into the gear's bore provides a positive mechanical stop that ensures correct alignment and orientation during assembly, serving as a foolproof mechanism against backwards installation.

Inventive Principle:

Principle #24Intermediary (Mediator)

2Reliability

If orientation features like flat surfaces and pins are added to the gear and spindle, then correct IGV orientation is ensured, but the device complexity increases

Engineering Contradiction:

Improvecorrect installation orientationVSAvoidnumber of orientation features

Core Design Contradiction:

ReliabilityVSDevice complexity

Solution Approach 1:

The gear is designed with an asymmetric flat surface instead of a symmetric circular shape, and the spindle has a corresponding asymmetric flat surface. This asymmetry creates a unique orientation where only one configuration allows the flat surfaces to align and engage the orientation pin, physically preventing incorrect installation while maintaining simple assembly procedures.

Inventive Principle:

Principle #4Asymmetry

Solution Approach 2:

The orientation pin acts as an intermediary element that mediates between the gear's flat surface and the spindle's flat surface. This pin protruding into the gear's bore provides a positive mechanical stop that ensures correct alignment and orientation during assembly, serving as a foolproof mechanism against backwards installation.

Inventive Principle:

Principle #24Intermediary (Mediator)

Data Source

PatentUS8033785B2Features to properly orient inlet guide vanes

Publication Date: 2011.10.11 GE INFRASTRUCTURE TECH LLC

AI summary

Several physical features on an inlet guide vane (IGV) ensure proper orientation of the IGV within a compressor during assembly. A gear with several teeth removed results in a flat surface on the gear which inhibits the gear from rotating on the rack of the compressor inlet casing. An orientation pin is located in the internal bore of the gear. The cylindrical IGV spindle has a portion formed as a flat surface and the orientation pin engages this flat surface. These features are applicable to both a one-piece IGV where the jackshaft is integrated with the IGV stem and a two-piece IGV in which the jackshaft is separate from the IGV stem. A feature applicable to a two-piece IGV is a shaped boss on the IGV stem that allows the jackshaft to be located on the IGV stem in only one orientation.