Self-Lubricating Blade Joint Bushing for Segmented Wind Turbines

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Wind turbine blades with multiple segments pose challenges in inspection and lubrication due to their large size and elevated, concealed installation locations, making in-situ maintenance dangerous and impractical.

Innovation Solution

A self-lubricating joint bushing with a tubular segment and a composite self-lubricating liner incorporating woven polytetrafluoroethylene fibers and structural reinforcement fibers within a polymer matrix, designed to withstand dithering and rotational sliding, featuring a mounting surface adhered to the tubular segment and a bearing surface to accommodate the shaft, along with locking features to secure the shaft.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Ease of manufacture

If segmented blades are used to facilitate manufacturing and transport, then the blade can be manufactured and transported in separate segments, but the joint requires lubrication and inspection that becomes dangerous and impractical at elevated installation locations

Engineering Contradiction:
Improveblade manufacturing and transportVSAvoidjoint lubrication and inspection
Core Design Contradiction:
Ease of manufactureVSEase of operation

Solution Approach 1:

The bushing incorporates a self-lubricating liner that provides lubrication automatically without requiring external intervention. The liner is pre-lubricated during manufacturing and provides sustained lubrication throughout the service life of the blade joint, eliminating the need for dangerous in-situ lubrication operations at elevated installation locations.

Inventive Principle:
Principle #25Self-service

Solution Approach 2:

The lubrication is applied in advance during the bushing manufacturing process rather than requiring later maintenance. The self-lubricating liner is pre-saturated with lubricant before installation, ensuring that lubrication is already in place before the blade is installed at its final elevated location, thereby avoiding the need for future lubrication operations.

Inventive Principle:
Principle #10Preliminary action

2Ease of operation

If traditional greased bushings are used in segmented blades, then the joint can be assembled, but the bushing requires periodic lubrication and inspection that is dangerous and impractical at elevated locations

Engineering Contradiction:
Improvejoint assemblyVSAvoidmaintenance requirements
Core Design Contradiction:
Ease of operationVSReliability

Solution Approach 1:

The self-lubricating liner serves itself by providing continuous lubrication without external intervention. The liner is designed to withstand dithering and rotational sliding while automatically providing lubrication, eliminating the need for periodic maintenance and inspection that would be required for traditional greased bushings.

Inventive Principle:
Principle #25Self-service

Solution Approach 2:

The invention changes the lubrication parameter from requiring periodic external application to providing continuous automatic lubrication. The self-lubricating liner transforms the maintenance regime by incorporating lubrication functionality directly into the bushing structure, changing it from a consumable that needs replenishment to a self-sustaining component.

Inventive Principle:
Principle #35Parameter changes

3Ease of manufacture

If the bushing is designed for easy assembly, then installation is simplified, but the bushing must withstand dithering and rotational sliding that cause wear and friction

Engineering Contradiction:
Improvebushing assemblyVSAvoidwear and friction resistance
Core Design Contradiction:
Ease of manufactureVSStrength

Solution Approach 1:

The bushing uses a composite construction with a self-lubricating liner that combines low-friction materials with structural support elements. The liner is fitted within the tubular bushing structure, creating a composite system that provides both ease of assembly and resistance to wear and friction from dithering and rotational sliding.

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

The self-lubricating joint bushing effectively reduces wear and friction, allowing for millions of cycles without maintenance, ensuring secure and reliable operation of segmented wind turbine blades under high loads and varying rotations.

Implementation Method 1

The bushing includes a self-lubricating liner having a mounting surface and a bearing surface. The self-lubricating liner is configured to withstand dithering and rotational sliding between the liner and a shaft extending therethrough.

Methodology Applied
Scientific EffectSelf-lubrication: Lubrication

Implementation Method 2

the self-lubricating liner includes a composite system incorporating plurality of woven polytetrafluoroethylene fibers intermixed with structural reinforcement fibers and encapsulated within a polymer matrix

Methodology Applied
Scientific EffectFriction reduction: Friction

Data Source

PatentEP3683439B1Multi segment wind turbine blade joint bushing
Publication Date: 2024.04.10 ROLLER BEARING OF AMERICA INC
  • EP3683439B1 patent drawingFigure 1A
  • EP3683439B1 patent drawingFigure 1B
  • EP3683439B1 patent drawingFigure 1C

AI summary

A joint bushing (10) that accommodates the dithering and sliding in multi segment wind turbines. The joint bushing (10) includes a self-lubricating liner (20) that is a composite system incorporating woven Polytetrafluoroethylene fibers intermixed with structural reinforcement fibers in a composite matrix. The composite system provides sufficient life without requiring re-lubrication.