PVC Pipe Repair Couplings Without Axial Movement or Flow Loss
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing methods for repairing or installing PVC pipes underground face challenges due to the need for axial movement to create gaps for solvent weld joints, which is impractical in tight spaces or underground environments, and previous solutions either reduce pipe diameter, causing flow restrictions or use O-rings with limited lifespan that may not meet regulatory standards.
Innovation Solution
A replacement pipe fitting assembly with sleeve bushings and special couplings that maintain the same diameter as the existing pipe, using solvent welding to secure bushings to the pipe ends and sliding couplings to form joints, eliminating the need for O-rings and ensuring compliance with pipe specifications.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If traditional solvent weld couplings are used for pipe repair, then joints can be securely made, but axial movement of about double the pipe length is required to create gaps and close them, which is impossible in close spaces or underground
Solution Approach 1:
The coupling device is divided into two separate couplings that can be independently positioned on each pipe end, eliminating the need for large axial movements. Each coupling is secured to its respective pipe end through solvent welding, allowing the pipes to be joined without requiring double the pipe length in axial movement space.
Solution Approach 2:
The couplings are preliminarily secured to the pipe ends through solvent welding before the actual joint is made. This preliminary action allows the couplings to be fixed in position, eliminating the need for subsequent axial movement to create gaps, thus solving the space constraint problem in underground or close-space installations.
2Ease of manufacture
If a smaller-diameter replacement pipe is used to accommodate couplings, then couplings can be slid onto the pipe ends, but the flow of water or fluid is throttled, creating a bottleneck
Solution Approach 1:
Instead of reducing the pipe diameter to accommodate couplings, the solution moves the coupling installation to a different dimensional approach by securing couplings to the external surfaces of the pipe ends through solvent welding. This allows the pipe internal diameter to remain unchanged, maintaining full fluid flow capacity while still enabling coupling installation.
3Ease of operation
If O-rings are used in replacement fittings to seal against leakage, then sliding connections can be made, but O-rings have limited life and many jurisdictions will not allow these repair devices to be buried underground
Solution Approach 1:
The mechanical sealing system using O-rings is replaced with a chemical bonding system using solvent welding. The couplings are secured to the pipe ends through solvent adhesive that creates a permanent, code-compliant joint without relying on elastomeric seals with limited lifespans. This substitution eliminates the reliability and code compliance issues associated with O-ring sealing while maintaining the sliding connection capability during installation.
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
Enables efficient, reliable, and compliant pipe repair or installation without reducing pipe diameter or using O-rings, allowing for secure and leak-proof connections that maintain fluid flow capacity.
Implementation Method 1
a sleeve bushing is attached to each of those pipe ends, adhered by the typical solvent adhesive
Data Source
AI summary
A broken pipe, such as a PVC water pipe, is repaired by cutting out a section and replacing that section with a special repair assembly. The replacement section is of at least the same diameter and specification, such as ASTM Schedule 40 PVC, as the existing line of pipe. The ends of the repair pipe section and ends of the existing pipe are provided with increased diameters, and special one-way couplings are provided to slide over the two joints, one at each end of the repair section, to solvent weld the joints together. In a modified procedure a single joint is made with the special coupling.