High Pressure Lip Seals with Anti-Extrusion and Anti-Galling Properties

Solution Overview

Problem

In dynamic applications, sealing assemblies face challenges with extrusion due to high pressure, where the sealing part can be extruded, and using high elastic modulus materials for supporting components risks damaging the shaft if they deflect and touch it.

Innovation Solution

The solution involves combining materials for the supporting component, using a high elastic modulus material for the inner arm and a lower elastic modulus material for the anti-extrusion ring, which can be made of anti-galling materials like bronze, to minimize extrusion gaps and prevent shaft damage, with an integrated lubricating area to reduce galling.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Strength

If a high elastic modulus material is used for the supporting component, then the supporting component can resist deflection under media pressure, but it may catastrophically damage the shaft if it touches the shaft due to deflection or vibration

Engineering Contradiction:

Improveresistance to deflectionVSAvoidshaft damage

Core Design Contradiction:

StrengthVSObject-affected harmful factors

Solution Approach 1:

The supporting component is designed with different materials in different regions: the inner surface that may contact the shaft is made of a softer material (lower elastic modulus) to prevent shaft damage, while the bulk of the component maintains high elastic modulus to resist deflection. This local differentiation of material properties resolves the contradiction between needing structural strength and avoiding harmful contact.

Inventive Principle:

Principle #3Local quality

Solution Approach 2:

The supporting component uses composite construction with multiple materials - typically a high elastic modulus material (such as steel) for the main body to provide structural strength and deflection resistance, combined with a lower elastic modulus material (such as bronze or other anti-galling materials) for the inner surface that may contact the shaft. This composite approach allows simultaneous achievement of both deflection resistance and shaft protection.

Inventive Principle:

Principle #40Composite materials

2Reliability

If the extrusion gap is reduced to minimize extrusion, then the supporting component may deflect and touch the shaft under high media pressure

Engineering Contradiction:

Improveresistance to extrusionVSAvoidshaft contact due to deflection

Core Design Contradiction:

ReliabilityVSObject-affected harmful factors

Solution Approach 1:

The supporting component is designed with different materials in different regions: the inner surface that may contact the shaft is made of a softer material (lower elastic modulus) to prevent shaft damage, while the bulk of the component maintains high elastic modulus to resist deflection. This local differentiation of material properties resolves the contradiction between needing structural strength and avoiding harmful contact.

Inventive Principle:

Principle #3Local quality

Solution Approach 2:

The softer material layer is placed on the inner surface of the supporting component as a protective cushion before any potential contact with the shaft. This pre-positioned softer layer acts as a buffer that will deform preferentially under pressure, preventing the harder structural material from contacting and damaging the shaft, thus cushioning against potential harmful effects in advance.

Inventive Principle:

Principle #11Beforehand cushioning (Prior cushioning)

3Object-affected harmful factors

If the supporting component is made entirely of low elastic modulus material for anti-galling purposes, then it becomes more prone to deflection under media pressure

Engineering Contradiction:

Improvegalling preventionVSAvoidresistance to deflection

Core Design Contradiction:

Object-affected harmful factorsVSStrength

Solution Approach 1:

The supporting component is designed with different materials in different regions: the inner surface that may contact the shaft is made of a softer material (lower elastic modulus) to prevent shaft damage, while the bulk of the component maintains high elastic modulus to resist deflection. This local differentiation of material properties resolves the contradiction between needing structural strength and avoiding harmful contact.

Inventive Principle:

Principle #3Local quality

Solution Approach 2:

The supporting component uses composite construction with multiple materials - typically a high elastic modulus material (such as steel) for the main body to provide structural strength and deflection resistance, combined with a lower elastic modulus material (such as bronze or other anti-galling materials) for the inner surface that may contact the shaft. This composite approach allows simultaneous achievement of both deflection resistance and shaft protection.

Inventive Principle:

Principle #40Composite materials

Data Source

PatentUS9234591B2High pressure lip seals with anti-extrusion and anti-galling properties and related methods

Publication Date: 2016.01.12 BAL SEAL ENG CO INC

AI summary

Sealing assemblies to provide sealing between a shaft and a housing comprising a sealing component comprising a body section as well as an outer flange and an inner flange both extending from said body section; a supporting component receiving said sealing component and comprising a relatively thick inner arm projecting into said sealing component and providing a supporting area spanning an inner portion of said body section and a portion of said inner flange; an anti-extrusion component engaged with said relatively thick inner arm; the minimum clearance between said anti-extrusion component and said shaft being less than the minimum clearance between said relatively thick inner arm and said shaft; said inner flange comprising a sealing area; wherein said sealing assembly is to be received in a cavity in said housing or on said shaft.