Non-bolt Joint Structure for Polyethylene Pipe Connection
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional non-bolt joint structures for connecting polyethylene pipes with metallic conduits require special polyethylene pipes with screw structures, which are costly and difficult to manufacture, and often result in disengagement due to aging of the second bulge portion.
Innovation Solution
A non-bolt joint structure where a polyethylene pipe is connected to a metallic conduit using a tubular inner core with a first bulge portion and a second bulge portion, where the inner core is plastically deformed to create a tapered shape that engages with the polyethylene pipe's outer surface, preventing disengagement without the need for bolts or special polyethylene pipes, and a packing ring seals the connection.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If a screw structure is used to connect polyethylene pipe with metallic conduit, then the connection can be achieved, but special polyethylene pipes with screw structures are required which increases manufacturing cost and complexity
Solution Approach 1:
The screw structure is extracted from the polyethylene pipe and transferred to the metallic conduit. The metallic conduit now carries the threading features while the polyethylene pipe returns to its simple cylindrical form, eliminating the need for special polyethylene pipe manufacturing.
Solution Approach 2:
A threaded insert or coupling mechanism serves as an intermediary element that connects the metallic conduit to the standard polyethylene pipe. This mediator allows threading to be present in the connection system without requiring the polyethylene pipe itself to have screw structures.
2Ease of operation
If the polyethylene pipe is deformed to create engagement features, then connection without bolts is achieved, but the second bulge portion ages and disengages over time
Solution Approach 1:
Instead of deforming the polyethylene pipe to create engagement features, the metallic conduit is deformed or equipped with engagement features that actively engage with the polyethylene pipe. This reverses which component undergoes deformation, preventing aging-related disengagement.
Solution Approach 2:
The metallic conduit is pre-formed with engagement features such as external threads or protrusions before installation. These features are designed to permanently engage with corresponding features in the polyethylene pipe or coupling, preventing future disengagement due to material aging.
3Strength
If the inner core is plastically deformed to create bulge portions, then engagement with polyethylene pipe is achieved, but manufacturing process complexity increases
Solution Approach 1:
The inner core undergoes controlled plastic deformation to change its geometric parameters, creating bulge portions with specific dimensions and shapes. This deformation is engineered to optimize engagement strength while maintaining manufacturability through standard forming processes.
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 solution allows for a secure, flexible, and cost-effective connection between polyethylene and metallic conduits without the need for special polyethylene pipes, reducing manufacturing costs and minimizing the risk of disengagement over time.
Implementation Method 1
the inner core is being deformed plastically to include a first bulge portion, a cross-sectional shape of the first bulge portion is curved so as to bulge toward an outward radial direction
Implementation Method 2
a second bulge portion is formed so that the insertion opening section of the polyethylene pipe is deformed so as to bulge toward the outward radial direction along the first bulge portion of the inner core
Implementation Method 3
a packing ring being inserted between the receiving opening section and the insertion opening section to seal between the receiving opening section and the insertion opening section
Implementation Method 4
an engaging means being provided with an inner circumference of the receiving opening section, the engaging means preventing the polyethylene pipe from disengaging from the receiving opening section by engaging with an outer circumferential surface of the polyethylene pipe
Data Source
AI summary
A non-bolt joint structure comprising; a packing ring sealing between a receiving opening section and an insertion opening section; an engaging means provided with an inner circumference of the receiving opening section preventing a polyethylene pipe from disengaging from the receiving opening section by engaging with an outer circumferential surface of the polyethylene pipe; and a tubular metallic inner core fitting an inner circumference of the insertion opening section of the polyethylene pipe, wherein the inner core is plastically deformed to include a first bulge portion that its cross-sectional shape bulges toward an outward radial direction, a second bulge portion is formed so that the insertion opening section of the polyethylene pipe bulges toward the outward radial direction along the first bulge portion of the inner core, and the polyethylene pipe is prevented from disengaging by the engaging means engaging with the outer circumferential surface of the second bulge portion.