Press Fitting Ribs and Displacement Chambers for Pipe Sealing
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Press fittings with O-rings and connecting pieces face issues with seal formation and require high pressing forces, especially when attaching larger diameter pipes, leading to potential misalignment and increased effort due to the initial lack of seal before pressing.
Innovation Solution
The design incorporates a pressing tool with internal ribs and displacement spaces on the connecting piece, allowing the central rib to align with the O-ring during pressing, and additional O-rings for redundancy, reducing the pressing force by accommodating pipe material displacement and ensuring a reliable seal even with incorrect tool positioning.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of operation
If the O-ring outer diameter is made smaller than the connecting piece outer diameter to enable easy pipe insertion, then the ease of operation is improved, but no seal can be achieved before pressing
Solution Approach 1:
The patent designs the connecting piece with a larger outer diameter than the O-ring to allow easy pipe insertion before pressing. The sealing action is prepared in advance through the geometric relationship between components, but the actual seal is only formed after the pressing action compresses the O-ring between the connecting piece and pipe.
2Reliability
If multiple ribs are used in the pressing tool to ensure proper pressing, then the reliability of pressing is improved, but the pressing force required increases
Solution Approach 1:
The pressing tool is divided into multiple ribs that are spaced apart along the longitudinal direction of the connecting piece. This segmentation allows the pressing force to be distributed across multiple contact points, ensuring proper deformation and positioning of the press fitting while reducing the total pressing force required compared to a single continuous pressing surface.
3Adaptability or versatility
If the connecting piece is designed with larger outer diameter for larger pipe diameters, then the adaptability is improved, but the pressing force required increases significantly
Solution Approach 1:
The pressing tool ribs are positioned at specific locations along the longitudinal direction of the connecting piece, creating localized pressing zones. This allows the pressing action to be applied where most needed for sealing and deformation, while the segmented design reduces the overall force requirement compared to uniform pressing across the entire circumference.
4Ease of operation
If the pipe rests directly on the rigid connecting piece without O-ring seal, then the ease of operation is improved, but the reliability of connection is reduced
Solution Approach 1:
The geometric design of the connecting piece with its larger outer diameter than the O-ring creates a clearance fit that facilitates easy pipe insertion. The sealing function is prepared for but not activated until the pressing operation compresses the O-ring between the connecting piece and pipe, transforming the connection from frictionless to sealed.
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 configuration allows for lower pressing forces, enabling the use of standard tools for larger pipe diameters, ensuring a reliable seal and reducing the risk of misalignment, with pressing forces below 30 KN for diameters up to 110 mm, maintaining tightness and safety.
Implementation Method 1
the outer diameter D - 2Δ of the O-ring is smaller than the largest outer diameter D - Δ of the connecting piece, so that no seal can be achieved between the O-ring and the pipe to be attached in the non-pressed state
Implementation Method 2
a pressing tool with several ribs spaced apart in the longitudinal direction of the connecting piece is necessary. The number of ribs in the pressing tool increases the necessary pressing force.
Data Source
Figure 1
Figure 2~3
Figure 4
AI summary
A press fitting (1) having at least one connection piece (2) for the mounting of a pipe (3), wherein the connection piece (2) has an encircling groove (5a) with an O-ring (6a) received therein, the outer diameter D - 2? of the O-ring (6a) being smaller than the largest outer diameter D - ? of the connection piece (2) and it thus not being possible, in the non-pressed state, for a sealing action to be achieved between the O-ring (6a) and the pipe (3) to be mounted, the connection piece (2) being designed to be pressed together, by means of a pressing tool, with multiple ribs (15a to 15c) spaced apart in the longitudinal direction of the connection piece (2), and one rib (15b) being positioned on the O-ring (6a) during the pressing process, characterized in that encircling displacement chambers (7a, 7b) are formed on the connection piece (2) in the region of the other ribs (15a, 15c), which displacement chambers can partially receive the material of the pipe (3) displaced by the ribs (15a, 15c), and the displacement chambers (7a, 7b) are arranged in the vicinity of the opening (2b) of the connection piece (2) and in the vicinity of the opposite end (2a) of the connection piece (2).