Pipeline Liner Assembly with Inflatable Bladder for Uniform Steam Curing

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Solution Overview

Problem

Conventional methods for installing liners in pipelines, such as excavation and 'cure-in-place' techniques, face challenges like high costs, time consumption, and difficulties with navigating transitional areas like bends and fittings, which hinder efficient pipeline repair and reinforcement.

Innovation Solution

A method involving a liner assembly with an outer tubular liner and an inner inflatable bladder, where the bladder is expanded with a steam-air mixture to ensure firm contact with the pipeline surface, allowing continuous flow for curing, and then deflated for retrieval, along with a portable steam generator to control temperature and flow rate for optimal curing.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If excavation methods are used to install liners, then the liner can be positioned in the pipeline, but the process becomes expensive, time consuming and disruptive

Engineering Contradiction:
Improveliner positioning reliabilityVSAvoidinstallation time
Core Design Contradiction:
ReliabilityVSLoss of time

Solution Approach 1:

The invention extracts the liner from the traditional excavation-based installation process and delivers it through the pipeline itself using a winch and cable system. The liner is pulled through the pipeline to the repair location and then expanded in place, eliminating the need for excavation while maintaining reliable positioning.

Inventive Principle:
Principle #2Taking out (Extraction)

Solution Approach 2:

The invention introduces an intermediary inflatable bladder that serves as a mediator between the liner and the pipeline. The bladder is inflated to expand the liner against the pipeline interior surface, ensuring firm contact and proper positioning without requiring excavation. This intermediary device enables the liner to be installed and positioned reliably through minimal access points.

Inventive Principle:
Principle #24Intermediary (Mediator)

2Ease of operation

If push-rods are used to move the liner, then the liner can be delivered to the pipeline, but transitional areas like bends and fittings create significant delivery problems

Engineering Contradiction:
Improveliner delivery easeVSAvoidadaptability to transitional areas
Core Design Contradiction:
Ease of operationVSAdaptability or versatility

Solution Approach 1:

The invention uses pneumatic principles by employing an inflatable bladder that can be expanded and contracted. This allows the liner to be pulled through transitional areas like bends and fittings in a compressed state, then expanded at the destination. The pneumatic expansion mechanism enables the system to adapt to various pipeline configurations without the delivery problems associated with rigid push-rods.

Inventive Principle:
Principle #29Pneumatics and hydraulics

Solution Approach 2:

The invention applies dynamics by using a winch and cable system that can dynamically pull the liner through the pipeline, rather than relying on static push-rods. The inflatable bladder also provides dynamic adaptability, allowing the liner to conform to bends and fittings during installation while maintaining firm contact with the pipeline surface at the repair location.

Inventive Principle:
Principle #15Dynamics

3Reliability

If the liner is pulled using a winch and cable, then the liner can be positioned at the desired location, but the process requires complex equipment and time for retrieval

Engineering Contradiction:
Improveliner positioning reliabilityVSAvoidequipment complexity
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The invention merges the positioning and installation functions into a single integrated process. The winch and cable system that pulls the liner to the repair location is combined with the inflatable bladder expansion mechanism, allowing the liner to be both delivered and installed using the same equipment setup. This reduces overall device complexity compared to separate positioning and installation systems.

Inventive Principle:
Principle #5Merging (Combining)

Solution Approach 2:

The inflatable bladder serves a dual function: it expands the liner against the pipeline surface for installation and also provides the retrieval mechanism after curing. The bladder can be deflated and pulled back through the pipeline using the same winch system, eliminating the need for separate retrieval equipment and reducing overall system complexity.

Inventive Principle:
Principle #25Self-service

4Reliability

If conventional curing methods are used, then the liner can be cured in place, but the curing process lacks temperature control and consistency

Engineering Contradiction:
Improvecuring reliabilityVSAvoidcuring temperature consistency
Core Design Contradiction:
ReliabilityVSTemperature

Solution Approach 1:

The invention ensures continuous flow of the steam-air mixture through the inflatable bladder during the entire curing process. This continuous flow maintains consistent temperature and curing conditions throughout the liner, eliminating the temperature variations and inconsistency associated with conventional curing methods. The steam generator operates continuously to provide steady thermal energy for uniform curing.

Inventive Principle:
Principle #20Continuity of useful action

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

This approach reduces installation time, increases efficiency, and allows for effective repair of both horizontal and vertical pipelines by maintaining consistent curing conditions, enhancing throughput and worker safety while avoiding the need for bulky equipment.

Implementation Method 1

introducing steam into the inflatable bladder so that the inflatable bladder expands to bring the tubular liner into firm contact with an interior surface of the pipeline

Methodology Applied
Scientific EffectSteam-air mixture expansion: Phase Change

Implementation Method 2

a water heater configured to heat water to generate steam

Methodology Applied
Scientific EffectWater heating: Heating

Implementation Method 3

an air heater configured to generate heated air

Methodology Applied
Scientific EffectAir heating: Heating

Implementation Method 4

the tubular liner being wetted with a curable compound... maintaining the liner assembly in an inflated condition for a time period sufficient for the tubular liner to cure

Methodology Applied
Scientific EffectThermal curing: Heat Treatment

Data Source

PatentEP3797240B1Liner assembly for pipelines and related method
Publication Date: 2024.05.01 NU FLOW TECH (2000) INC
  • EP3797240B1 patent drawingFigure 1
  • EP3797240B1 patent drawingFigure 2~3
  • EP3797240B1 patent drawingFigure 4a~4c

AI summary

A method of installing a liner assembly for pipeline repair or reinforcement includes: pulling a prepared liner assembly into position in the pipeline, the liner assembly including an outer tubular liner and an inner inflatable bladder positioned longitudinally within the tubular liner, the tubular liner being wetted with a curable compound; introducing fluid into the inflatable bladder so that the inflatable bladder expands to bring the tubular liner into firm contact with an interior surface of the pipeline; flowing the fluid continuously through the bladder and discharging the fluid into the pipeline, while maintaining the liner assembly in an inflated condition for a time period sufficient for the tubular liner to cure; and deflating the inflatable bladder and retrieving at least a portion of the liner assembly from the pipeline.