Self-Energizing Flange Connection for Fatigue-Resistant Sealing
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Wind tower flanges face high cycling loads and fatigue issues due to bending moments, and existing L-type flanges with high displacement openings pose challenges for implementing additional sealing systems to protect against environmental conditions.
Innovation Solution
A flange connection system featuring self-energized flange rings with a neck and radially extending portions, including a stepped contact surface and seal pockets, which creates a static connection with high contact pressure for fatigue resistance and self-sealing capabilities, eliminating the need for additional sealing elements.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of operation
If L-type flanges with high displacement opening are used, then ease of assembly is improved, but sealing capability deteriorates
Solution Approach 1:
The flange face is segmented into multiple contact zones (first contact zone, second contact zone, and third contact zone) with different functions. The first contact zone provides sealing, the second provides structural connection, and the third provides additional sealing or support, allowing each zone to be optimized independently for its specific function.
Solution Approach 2:
Different regions of the flange contact surface are given different properties through the stepped configuration. The first contact zone has a first step height for sealing, the second contact zone has a second step height for structural connection, and the third contact zone has a third step height for additional sealing or support, creating local quality variations that address different requirements simultaneously.
2Reliability
If additional sealing elements are added to L-type flanges, then sealing capability is improved, but device complexity increases
Solution Approach 1:
The sealing function is merged into the flange structure itself through the stepped contact zones. The first contact zone and third contact zone provide sealing functionality directly through their geometric configuration, eliminating the need for separate sealing elements in many cases. When sealing elements are used, they are integrated into the seal pockets formed by the stepped configuration rather than being separate components.
Solution Approach 2:
The flange structure provides its own sealing capability through the stepped contact zones that create natural seal pockets. The geometry of the first, second, and third contact zones themselves creates the sealing mechanism, allowing the flange to seal without requiring additional sealing elements, thus making the system self-sufficient.
3Stability of the object's composition
If contact force is increased to prevent loosening under bending loads, then connection stability is improved, but fatigue resistance deteriorates
Solution Approach 1:
The flange rings are designed to be self-energizing, where the contact forces are dynamically generated by the bending loads themselves. As bending moments increase, the flange rings warp and generate higher contact forces in the first and third contact zones, automatically increasing the clamping force to prevent loosening without requiring pre-tensioned bolts that would create fatigue issues.
Solution Approach 2:
The contact force parameter changes dynamically with the loading conditions. The stepped configuration creates different stiffness characteristics in different zones, allowing the contact forces to redistribute automatically under bending loads. The first contact zone experiences higher contact forces under bending while the second contact zone maintains structural connection, optimizing both stability and fatigue resistance.
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
The system provides a robust, fatigue-resistant connection that maintains stability under bending and tensile loads while sealing effectively, enhancing protection against environmental conditions without additional sealing elements.
Implementation Method 1
self-energized flange ring (by warping) controlled by the flange step to gain a proper contact forces profile on the flange face
Implementation Method 2
a first seal ring is disposed in the first seal pockets, and a second seal ring is disposed in the second seal pockets between the pair of flange rings
Data Source
Figure 1~2
Figure 3~5
Figure 6~7
AI summary
A flange connection system, including a pair of flange rings each including a neck portion and a radially extending flange portion. The radially extending flange portion includes a distal face including a contact surface that protrudes from a remainder of the distal face. The radially extending flange portion includes a plurality of circumferentially spaced bolt holes extending parallel to a center axis. The distal face including a first seal pocket radially inward of the contact surface and a second seal pocket radially outward of the contact surface, wherein in an assembled condition, the contact surface of the first flange ring is disposed against the contact surface of the second flange ring, a first seal ring is disposed in the first seal pockets, and a second seal ring is disposed in the second seal pockets.