Pipe Expander Head With Grooved Spreading Elements for Sealing
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing expander tools often cause deformations on the inner surface of pipes, leading to reduced sealing effectiveness when a pipe fitting is inserted, as the expanding elements do not leave a smooth, intact surface.
Innovation Solution
The expander tool features radially movable spreading elements with circumferential grooves and a conical design, allowing for expansion while maintaining an undamaged sealing surface, aided by a piston and actuator system, and incorporating a guide flange with an elastic O-ring for returning the elements to their initial position.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If spreading elements are used to expand the pipe end, then the pipe end can be expanded to accommodate fittings, but deformations are formed on the inner surface of the pipe reducing sealing effectiveness
Solution Approach 1:
The spreading elements are designed with differentiated surface features: smooth sealing surfaces in contact with the pipe inner wall to prevent deformations, and gripping surfaces with deformations for holding the spreading elements during operation. This local quality differentiation ensures both effective pipe expansion and maintained sealing capability.
Solution Approach 2:
A membrane is introduced as an intermediary between the spreading elements and the pipe inner surface. The membrane transfers the expansion force while protecting the pipe's sealing surface from direct contact with the spreading elements' deformations, thus maintaining sealing effectiveness.
2Strength
If spreading elements are made with gripping surfaces for holding, then the spreading elements can be securely held during operation, but deformations are transferred to the pipe inner surface
Solution Approach 1:
The spreading elements feature locally differentiated surfaces: smooth sealing surfaces that contact the pipe to prevent deformations, and separate gripping surfaces with deformations for secure holding. This localized functional differentiation allows both strong holding capability and preservation of sealing surface integrity.
Solution Approach 2:
The spreading elements are segmented into distinct functional zones: a sealing surface portion that remains smooth and contacts the pipe, and a gripping surface portion with deformations for tool engagement. This segmentation prevents deformation transfer to the sealing surface.
3Length of stationary object
If the pipe is expanded using conventional tools, then the pipe end can be enlarged, but the sealing area is damaged requiring additional processing
Solution Approach 1:
The spreading elements incorporate smooth sealing surfaces specifically designed to contact the pipe inner wall during expansion, preventing deformations on the sealing area. This allows the pipe end to be enlarged while the sealing surface remains smooth and intact.
Solution Approach 2:
A protective membrane acts as an intermediary between the spreading elements and the pipe's sealing surface, transferring expansion forces while preserving the sealing area's smoothness and integrity throughout the expansion process.
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 design ensures a tight seal between the pipe and the fitting by creating undamaged, smooth sealing surfaces, even after expansion and subsequent contraction of pipes with shape memory materials, maintaining sealing integrity.
Implementation Method 1
incorporating a guide flange with an elastic O-ring for returning the elements to their initial position
Implementation Method 2
expanding an end of a pipe made of plastics having shape memory
Data Source
Figure 1~2
Figure 3~5
Figure 6~8
AI summary
An expander tool comprising a tool head which comprises expanding means arranged to be insertable inside the end of the pipe (P) for expanding the end of the pipe. The expanding means comprise a plurality of spreading elements (4). The spreading elements (4) are radially movable in relation to a center longitudinal axis (x) of the tool head between a starting position and an outwardly extended expansion position (II) radially distanced from the axis (x) so as to expand the end of the pipe. Each of the spreading elements (4) have an outer spreading surface. The outer spreading surfaces are configured to press against an interior surface of the end of the pipe (P). The expander tool comprises a piston (6) configured to spread the spreading elements (4) from the starting position to the expansion position (II) by moving along said axis (x) from a retracted piston position to a fully extended piston position (IV) against interior surfaces of the spreading elements (4), and an actuator (7) for moving the piston (6). The outer spreading surfaces comprise a circumferential groove (8). The groove (8) leaves an undamaged smooth and intact sealing surface to the inner surface of the expanded pipe (P).