Trenchless Pipeline Rod Linkage With Arcuate Plug Coupling

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing linkages for trenchless pipeline rehabilitation face challenges with high assembly effort and reduced service life due to threaded connections, which become cumbersome and prone to jamming when used in powerful linear traction devices, especially under bending moments.

Innovation Solution

A linkage system where sections are connected via a plug-in coupling with arcuate contact surfaces and locking mechanisms, allowing for efficient force distribution and preventing bending moments, featuring transverse openings and webs that maintain contact under tensile and compressive loads, and include locking elements to prevent kinking.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Ease of operation

If threaded connections are used to connect rod sections, then the linkage can be assembled, but the assembly effort increases significantly and the service life decreases due to jamming and wear

Engineering Contradiction:
Improveassembly effortVSAvoidservice life
Core Design Contradiction:
Ease of operationVSReliability

Solution Approach 1:

The connection system is divided into separate male and female components with distinct geometric features (transverse web and transverse opening) that enable quick assembly without threading operations. Each rod section retains its functional integrity while allowing rapid connection and disconnection.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The arcuate contact surfaces replace flat threaded interfaces, creating curved mating surfaces that distribute loads more uniformly and prevent stress concentration. The arcuate geometry inherently resists bending moments and eliminates the jamming problem associated with threaded connections.

Inventive Principle:
Principle #14Spheroidality (Curvature)

2Ease of manufacture

If flat contact surfaces are used in plug-in connections, then assembly is simple, but bending moments cause unfavorable stress distribution that reduces service life

Engineering Contradiction:
Improveconnection simplicityVSAvoidservice life under bending moment
Core Design Contradiction:
Ease of manufactureVSReliability

Solution Approach 1:

The patent replaces flat contact surfaces with arcuate (curved) contact surfaces that conform to each other. This curved geometry allows the connection to accommodate bending moments by distributing stresses along the arc, preventing the unfavorable stress concentration that occurs with flat surfaces under combined loading conditions.

Inventive Principle:
Principle #14Spheroidality (Curvature)

3Adaptability or versatility

If threaded connections are used, then mechanical release and connection devices can be provided, but the threaded parts must be kept clean to prevent jamming and wear

Engineering Contradiction:
Improvemechanical release and connection capabilityVSAvoidmaintenance effort
Core Design Contradiction:
Adaptability or versatilityVSEase of operation

Solution Approach 1:

The connection system uses separable male and female components with geometric interlocking features rather than threaded interfaces. This segmentation allows for easy assembly and disconnection without the need for threading operations, and the simple geometric interfaces are less susceptible to contamination and jamming.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The problematic threaded connection mechanism is extracted and replaced with a simpler plug-in system using transverse webs and openings. This removes the source of maintenance problems (threaded parts requiring cleaning) while retaining the essential function of mechanical connection and release.

Inventive Principle:
Principle #2Taking out (Extraction)

Data Source

PatentEP2520755B1Rod and device for retrofitting pipelines without digging
Publication Date: 2019.06.05 TRACTO TECHN
  • EP2520755B1 patent drawingFigure 1
  • EP2520755B1 patent drawingFigure 2
  • EP2520755B1 patent drawingFigure 3

AI summary

The rod (2) has two rod sections, which are connected with each other by a plug connector. One of the two rod sections has a transverse opening at an end. A transverse bar is inserted in the transverse opening at end of the other rod section. Front surfaces of the transverse opening and the transverse bar are formed in curved shape. The front surfaces of the transverse opening and the transverse bar are pressed against each other due to a tensile load of the rod. An independent claim is included for a device for non-grave redevelopment of pipe lines.