Nondestructive Pipe Expansion Tool for Trenchless Refurbishment
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current trenchless methods for refurbishing expandable metal culverts are inadequate, as they often destroy the host pipe, leading to reduced operational diameter and increased costs due to accordion-like compression and potential tool sticking, especially in corrugated pipes.
Innovation Solution
A method using a cylindrical hydraulic tool that applies radial force perpendicular to the host pipe's longitudinal axis to expand it non-destructively, either by smoothing out waves or making longitudinal cuts, allowing for the installation of a new liner pipe without compromising the host pipe's structural integrity.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of operation
If destructive pipe bursting methods are used to replace damaged culverts, then new liner pipes can be installed with minimal traffic disruption, but the host pipe is destroyed and operational diameter is reduced
Solution Approach 1:
The expansion tool is divided into multiple expandable segments or blades that can be independently controlled. These segments expand radially to push against the host pipe walls, allowing controlled expansion without destroying the overall pipe structure. The segmentation enables localized force application while maintaining pipe integrity.
Solution Approach 2:
The expansion tool transitions from a compact transport state to an expanded operational state. The tool's blades or segments are dynamically deployable, expanding radially when needed to push against the host pipe, then retracting for removal. This dynamic transformation allows the tool to perform its expansion function without permanently altering the host pipe structure.
2Adaptability or versatility
If expandable metal culverts are used to provide flexibility and strength, then they remain relatively light and inexpensive, but they are prone to rust, corrosion, and structural failure over time
Solution Approach 1:
The solution creates a composite structure by installing a corrosion-resistant liner pipe inside the existing metal host pipe. The host pipe retains its structural strength and flexibility, while the liner pipe provides protection against rust and corrosion. This composite approach combines the advantages of both materials - the mechanical properties of metal with the chemical resistance of liner materials.
Solution Approach 2:
The liner pipe acts as a protective barrier installed beforehand to prevent future corrosion and structural degradation. By lining the host pipe with a corrosion-resistant material, the system preemptively protects against the harmful effects of moisture and chemicals that would otherwise cause rust and failure of the metal structure.
3Productivity
If conventional pipe bursting tools are used on corrugated pipes, then installation can proceed, but accordion-like compression causes tool sticking and increased costs
Solution Approach 1:
The expansion tool applies radial force locally at specific points around the pipe circumference rather than attempting to burst the pipe longitudinally. This localized radial expansion smoothly pushes against the corrugations without causing accordion-like compression, preventing tool sticking while maintaining installation efficiency.
4Reliability
If open cut methods are used to repair culverts, then damaged sections can be completely replaced, but traffic must be closed and the process is time-consuming
Solution Approach 1:
The new liner pipe is nested inside the existing host pipe, creating a pipe-within-a-pipe configuration. This nesting approach allows complete replacement of the damaged inner lining while preserving the outer structural pipe, eliminating the need for excavation and traffic closure associated with traditional open-cut replacement methods.
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 preserves the host pipe's structural integrity, maintains operational diameter, and reduces the likelihood of tool sticking and increased costs by ensuring the host pipe supports the new liner pipe effectively, enhancing the refurbishment's success rate and longevity.
Implementation Method 1
a cylindrical hydraulic tool that applies radial force perpendicular to the host pipe's longitudinal axis to expand it non-destructively
Implementation Method 2
applies radial force perpendicular to the host pipe's longitudinal axis to expand it non-destructively, either by smoothing out waves or making longitudinal cuts
Data Source
AI summary
A method for refurbishing an existing expandable host pipe. An expansion tool is adapted to generate isolated outward radial force when in expansion mode. The expansion tool is moved along a path inside the host pipe, stopping at stations on the way. At each station, responsive to isolated outward radial force from the expansion tool, the unobstructed interior diameter of the host pipe is increased via non-destructive plastic deformation of the interior wall. Once the entire host pipe is expanded in this fashion, a new rigid liner pipe is inserted inside the host pipe to operationally replace the host pipe. Grout is deployed in the annular space between liner pipe and host pipe. Expansion of the host pipe via non-destructive plastic deformation optimizes the refurbishment job and enables the original host pipe, as expanded, to contribute structurally to the refurbished pipe system.