Press Sleeve Retaining Tabs Prevent Axial Slippage

Solution Overview

Problem

Existing compression sleeves for pipe connections often slip off the fitting base body and can leak under bending or tensile loads, leading to unreliable metal-to-metal sealing connections.

Innovation Solution

A compression sleeve with radially resilient retaining tabs that secure the sleeve against axial displacement, providing a positive form-fitting connection with the fitting base body, either by penetrating its material or engaging with a recess, to prevent slipping and enhance sealing integrity.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If a conventional compression sleeve is used for pipe connections, then the connection can be made in a metallically sealing manner, but the sleeve may slip off the fitting base body under certain circumstances

Engineering Contradiction:

Improveconnection reliabilityVSAvoidaxial displacement resistance

Core Design Contradiction:

ReliabilityVSEase of operation

Solution Approach 1:

The retaining tabs are pre-formed on the compression sleeve before assembly, positioned to engage with the fitting base body. This preliminary preparation ensures that as soon as the sleeve is installed, the tabs are already in position to prevent axial displacement, eliminating the need for additional securing steps and ensuring immediate resistance to slipping under load.

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The compression sleeve is segmented with multiple retaining tabs distributed around its circumference. This segmentation allows the sleeve to maintain radial compression force while simultaneously providing multiple discrete engagement points with the fitting base body, preventing axial displacement without compromising the overall sealing function.

Inventive Principle:

Principle #1Segmentation

2Device complexity

If a conventional compression sleeve is used, then the structure remains simple, but leaks can occur at the pressed connection under bending or tensile loads

Engineering Contradiction:

Improvesleeve structure complexityVSAvoidsealing integrity

Core Design Contradiction:

Device complexityVSReliability

Solution Approach 1:

The retaining tabs are pre-formed on the compression sleeve before assembly, positioned to engage with the fitting base body. This preliminary preparation ensures that as soon as the sleeve is installed, the tabs are already in position to prevent axial displacement, eliminating the need for additional securing steps and ensuring immediate resistance to slipping under load.

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The compression sleeve is segmented with multiple retaining tabs distributed around its circumference. This segmentation allows the sleeve to maintain radial compression force while simultaneously providing multiple discrete engagement points with the fitting base body, preventing axial displacement without compromising the overall sealing function.

Inventive Principle:

Principle #1Segmentation

3Strength

If the compression sleeve is pushed on axially to deform the fitting body radially, then a metal-to-metal connection is achieved, but the sleeve may loosen axially after assembly

Engineering Contradiction:

Improvemetal-to-metal connection strengthVSAvoidaxial position stability

Core Design Contradiction:

StrengthVSStability of the object's composition

Solution Approach 1:

The retaining tabs are pre-formed on the compression sleeve before assembly, positioned to engage with the fitting base body. This preliminary preparation ensures that as soon as the sleeve is installed, the tabs are already in position to prevent axial displacement, eliminating the need for additional securing steps and ensuring immediate resistance to slipping under load.

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The retaining tabs are integrated as an integral part of the compression sleeve, combining the sealing function and the axial retention function into a single component. This merging eliminates the need for separate retaining elements and ensures that the axial position stability is achieved through the same component that provides the metal-to-metal connection.

Inventive Principle:

Principle #5Merging (Combining)

4Reliability

If a two-part compression sleeve construction is used, then axial displacement can be prevented, but the manufacturing complexity and cost increase

Engineering Contradiction:

Improveaxial displacement preventionVSAvoidmanufacturing simplicity

Core Design Contradiction:

ReliabilityVSEase of manufacture

Solution Approach 1:

The retaining tabs are integrated as an integral part of the compression sleeve, combining the sealing function and the axial retention function into a single component. This merging eliminates the need for separate retaining elements and ensures that the axial position stability is achieved through the same component that provides the metal-to-metal connection.

Inventive Principle:

Principle #5Merging (Combining)

Solution Approach 2:

The compression sleeve is designed with varying wall thicknesses, with thicker sections at the retaining tabs to provide the necessary radial resilience and axial retention force. This parameter change allows the single-component design to achieve the functionality of a two-part construction while maintaining manufacturing simplicity.

Inventive Principle:

Principle #35Parameter changes

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 solution effectively prevents axial loosening and leakage, ensuring a robust and reliable metal-to-metal sealing connection by increasing friction and providing a secure axial fixation, even under load, while being cost-effective and simple to produce.

Implementation Method 1

at least one retaining tab (10) is provided in the receiving section (4) which can be resiliently braced inward in the radial direction

Methodology Applied

Scientific EffectElasticity: Elasticity

Implementation Method 2

the radial clamping forces increasing the friction between the compression sleeve and the fitting base body, which counteracts an axial loosening

Methodology Applied

Scientific EffectFriction: Friction

Implementation Method 3

The fitting body and the pipe end are plastically deformed and pressed together by the axial sliding of the compression sleeve

Methodology Applied

Scientific EffectPlastic deformation: Plasticity

Data Source

PatentEP3265711B1Press sleeve, press fitting and use of the press fitting or the press sleeve

Publication Date: 2019.04.03 VIEGA TECHNOLOGY GMBH & CO KG

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Figure 4~5

AI summary

The invention relates to a press sleeve for a press fitting for producing a sealing non-detachable pipe connection, with a receiving portion (4) for receiving a fitting basic body (6) and with a press portion (8), wherein the inside diameter of the receiving portion (4) is adapted to the outside diameter of the fitting basic body (6) and wherein the inside diameter of the press portion (8) is designed to be smaller than the outside diameter of the fitting basic body (6) at least in certain sections. The press sleeve is distinguished by the fact that at least one retaining lug (10) which can be clamped resiliently inwards in the radial direction (R) is provided in the receiving portion (4) and that the retaining lug (10) has a free end portion (12) which, with the retaining lug (10) in the stress-relieved state, protrudes at least partially into the inner region of the receiving portion (4) in the radial direction (R).