Sewer Hose Liner Outer Film for UV-Safe Resin Curing
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing hose liners for sewer renovation lack mechanical robustness and are prone to premature resin hardening, leading to increased costs and potential damage during insertion into sewer pipes.
Innovation Solution
A hose liner with a robust outer film system that provides mechanical strength and UV protection, featuring high tear and puncture resistance, and a design that prevents premature resin hardening, using a single or multiple overlapping outer films with high mechanical properties and UV/light protection layers, and a fleece or nonwoven for improved resin bonding.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Strength
If a thick-walled HDPE liner is used as insert, then mechanical strength is improved, but the liner becomes vulnerable to UV radiation causing premature resin hardening
Solution Approach 1:
A UV-protective film is introduced as an intermediary layer between the HDPE liner and the resin carrier system. This film blocks UV radiation from reaching the resin, preventing premature hardening while allowing the HDPE liner to maintain its mechanical strength. The film acts as a mediator that protects the resin from harmful UV exposure during storage and handling.
Solution Approach 2:
The solution combines multiple materials with different properties: the HDPE liner provides mechanical strength and puncture resistance, while the UV-protective film provides optical protection. This composite structure leverages the strengths of each material to solve both the mechanical strength requirement and the UV protection requirement simultaneously.
2Reliability
If multiple layers with different functions are added to protect against UV and provide mechanical strength, then protection capability is improved, but device complexity increases
Solution Approach 1:
The UV-protective film is integrated directly with the resin carrier system, merging the protection function into the existing structure rather than adding it as a separate, complex assembly. This integration maintains protection capability while avoiding the complexity of multiple independent components.
Solution Approach 2:
The outer film system serves multiple functions: it provides UV protection, maintains mechanical integrity, and allows for controlled resin containment. By designing the film system to perform multiple functions simultaneously, the patent avoids the need for separate components for each function, thereby reducing overall complexity.
3Strength
If the outer film is made highly robust against mechanical influences, then damage resistance during insertion is improved, but the film may interfere with UV curing process
Solution Approach 1:
The film structure is designed with spatially varying properties: the outer surface facing the resin provides UV protection and mechanical strength, while the inner surface in contact with the resin remains permeable to UV radiation for curing. This local differentiation of film properties allows simultaneous achievement of damage resistance and UV curing efficiency.
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 hose liner achieves cost-effective design with enhanced mechanical stability, preventing damage during insertion and ensuring complete resin containment, while maintaining effective UV curing through permeable inner films.
Implementation Method 1
the outer film system... prevents premature curing of the resin (e.g., during storage) by simultaneously acting as a UV-protective film
Implementation Method 2
maintaining effective UV curing through permeable inner films
Data Source
Figure 1
Figure 2
Figure 3
AI summary
The invention relates to a pipe liner (1) for sewer rehabilitation, comprising at least: - an inner lining (2); - a resin carrier layer (3) surrounding the inner lining (2), wherein the resin (3b) is curable by means of UV radiation; - a mechanically protective outer lining system (7) surrounding the resin carrier layer (3) with at least one outer lining (7a; 7a, 7b) extending in the longitudinal direction of the pipe liner (1), wherein the longitudinal edges (8) of the outer lining (7a) or the outer linings (7b, 7c) are overlapping and connected to each other in the circumferential direction of the pipe liner (1), wherein the resulting at least one connection point (9) stretches and may break when the pipe liner (1) is stretched in the radial direction during insertion into a sewer to be rehabilitated.The pipe liner is characterized by the fact that - the at least one outer film (7a; 7b, 7c) each has at least one layer of a mechanically very stable and essentially non-stretchable or only very poorly stretchable material, - the at least one outer film (7a; 7b, 7c) has at least one layer that is essentially impermeable to UV radiation and possibly visible light.