Reusable Inversion Sleeve Assembly for Cured-in-Place Liners
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current methods for installing cured-in-place pipe liners using water inversion and hot water cure are inefficient due to high water requirements and increased forces needed for inversion, which can damage the liner and existing conduit, especially for medium and large diameter pipes.
Innovation Solution
A reusable inversion sleeve assembly with a dual gland apparatus allows for air inversion and steam curing without deflating the liner, using a lay flat hose for steam introduction and a hold-back strap to manage forces, reducing the need for water and shortening the cure cycle.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If water inversion and hot water cure methods are used, then the liner can be installed and cured, but high water requirements and increased forces are needed which can damage the liner and existing conduit
Solution Approach 1:
The patent changes the inversion medium from water to air, and the curing medium from hot water to steam. This parameter change reduces water consumption significantly while maintaining the effectiveness of the inversion and curing processes. The air inversion reduces hydrostatic pressure forces that could damage the liner or conduit, and steam curing provides sufficient heat without the mechanical forces of water injection.
Solution Approach 2:
The patent employs pneumatic principles by using air pressure for inversion instead of hydraulic water pressure. The dual gland apparatus controls air pressure to invert the liner safely. For curing, steam (a gas phase) is used instead of liquid water, leveraging phase change properties to deliver heat without the damaging mechanical forces of liquid injection.
2Ease of operation
If water inversion method is used, then the liner can be inverted, but the high forces needed can damage the liner and existing conduit
Solution Approach 1:
The patent changes the inversion medium from water to air, fundamentally altering the pressure characteristics. Air pressure provides sufficient force for inversion without the high hydrostatic pressure of water that causes damaging forces on the liner and conduit. The dual gland apparatus precisely controls air pressure application to achieve safe and effective inversion.
3Productivity
If traditional single gland apparatus is used, then the liner can be inverted, but the setup time is increased and water consumption is high
Solution Approach 1:
The patent combines multiple functions into a single dual gland apparatus: air inversion control, steam curing delivery, and liner positioning. The first gland handles air pressure for inversion while the second gland manages steam injection and hold-back strap passage. This integration eliminates the need for separate water-based systems and reduces setup time by having all functions available in one apparatus.
Solution Approach 2:
The patent changes from water-based inversion and curing to air/steam-based processes. This parameter change eliminates high water consumption requirements while maintaining effective inversion and curing capabilities. The dual gland apparatus is specifically designed to control air and steam parameters for efficient installation.
4Productivity
If the liner is deflated before steam introduction, then the steam can be introduced, but the installation time increases and the process becomes more complex
Solution Approach 1:
The patent prepares the dual gland apparatus in advance with the hold-back strap and steam delivery system positioned before inversion begins. The first gland is configured to allow strap passage during inversion, and the second gland is pre-positioned for immediate steam introduction. This preliminary arrangement eliminates the need to deflate the liner and reconfigure equipment during the curing phase.
Solution Approach 2:
The patent uses a dynamic dual gland system where the glands can be independently opened and closed at different stages of the process. During inversion, the first gland controls air pressure while the second gland remains closed. During curing, the first gland closes and the second gland opens for steam introduction. This dynamic control allows seamless transition between inversion and curing without deflating the liner.
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 method reduces the time and effort required for installation, conserves water, and effectively seals and strengthens the pipeline while avoiding damage to the existing conduit, making it suitable for medium and large diameter pipes.
Implementation Method 1
The liner is then inverted by introduction of air for inversion into the conduit
Implementation Method 2
subsequently introducing steam into the inverted liner through a flexible hose to cure the liner
Implementation Method 3
cure the liner
Data Source
AI summary
Installation of a flexible cured in place liner by inverting the liner utilizing an inversion sleeve assembly with an installation apparatus having at least one selectively operable rigid gland. The sleeve assembly includes a sleeve portion of an absorbable material secured in an apparatus with an inversion boot fitted at the distal end with an inlet port for inversion and/or curing fluid. The sleeve assembly and apparatus are particularly well suited for inverting with air and curing the liner with steam introduced through a perforated lay flat hose using an apparatus with two glands. The installation sleeve is the same dimension as the liner to be installed and is reusable thereby substantially reducing the set up time to install using the dual gland apparatus. Preferably, the flexible sleeve is a length of dry cured in place liner inverted on to itself to expose two impregnable surfaces. The sleeve may have a built in fluid inlet port for use with a dual gland apparatus.