Polyurethane Coating for Tribological Surfaces
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing solutions for reducing friction between sliding machine components, such as lubricants, face limitations like the absence of a lubricating layer at startup and the softness of low-friction materials like PTFE, which complicates durable application.
Innovation Solution
A process involving the application of a polymer formulation containing isocyanate and isocyanate-reactive polyol to form polyurethanes on tribological surfaces, providing a durable low-friction coating that can be cured to enhance the wear resistance and reduce friction before machine operation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Force
If PTFE coating is applied to reduce friction, then low-friction properties are improved, but durability and ease of application deteriorate due to softness of the material
Solution Approach 1:
The patent applies a multi-layer composite coating system where a PTFE layer is combined with a polyurethane primer layer and an intermediate layer. The PTFE provides low-friction properties while the polyurethane and intermediate layers provide adhesion and structural support, resolving the contradiction between low friction and durability.
Solution Approach 2:
The patent modifies the PTFE coating by controlling its thickness (10-20 micrometers) and combining it with properly formulated polyurethane compositions. By adjusting the parameters of the coating system (thickness, composition, curing conditions), the patent achieves both low friction and improved durability.
2Force
If lubricant is used to reduce friction, then friction reduction is improved, but reliability deteriorates because the lubricating layer is absent at startup and only forms after reaching a particular temperature
Solution Approach 1:
The patent applies a PTFE coating and polyurethane primer layer beforehand (before operation) to create a durable low-friction surface that is immediately effective at startup. This preliminary protective layer eliminates the startup friction problem associated with lubricants that require temperature-dependent film formation.
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 polyurethane coating effectively reduces friction and improves the fatigue life of machine components in bearing and seal applications by providing a low-friction surface that is durable and resistant to wear, even in the absence of a lubricating layer.
Implementation Method 1
a polymer formulation provides an isocyanate that contains two or more isocyanate groups per molecule and an isocyanate-reactive polyol to form polyurethanes
Implementation Method 2
subjecting at least part of the coating as obtained in step (a) to a curing treatment during which polyurethanes are formed in the coating
Data Source
AI summary
A process for preparing a coating on at least part of a tribological surface of a first machine component which, during machine operation, is adapted to be in sliding contact with a tribological surface of a second machine component is provided. The process provides the steps of: (a) applying a polymer formulation onto at least part of the tribological surface of the first machine component to form a coating. The polymer formulation provides an isocyanate that contains two or more isocyanate groups per molecule and an idocyanate-reactive polyol to form polyurethanes; and (b) subjecting at least part of the coating as obtained in step (a) to a curing treatment during which polyurethanes are formed in the coating on the at least part of the tribological surface of the first machine component.