Valve Disc Thickness Distribution for Flow Loss and Strength
Solution Overview
Problem
Existing valve fittings face challenges in balancing low flow resistance and high strength, as thin valve discs minimize flow loss but compromise on strength, while thickening for strength increases flow disruption, and conventional connections suffer from wear and torsional resistance issues.
Innovation Solution
The valve disc is designed with a thickening towards its peripheral area, with the housing contour following the disc's contour to maintain a constant cross-sectional flow area, reducing flow losses and enhancing strength by ensuring parallel contours in the flow channel.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Loss of energy
If the valve disc is made thin to minimize flow resistance, then flow loss is reduced, but the strength of the valve disc is compromised
Solution Approach 1:
The valve disc is designed with non-uniform thickness distribution, featuring localized thickening in specific areas (such as the peripheral area or pressure-bearing zones) while maintaining thinner sections in other areas. This local quality variation allows the disc to achieve both low flow resistance overall and sufficient strength at critical locations, resolving the contradiction between thin design for flow efficiency and thick design for strength
2Strength
If the valve disc is thickened to increase strength, then the valve disc can withstand higher forces, but flow disruption increases and flow losses increase
Solution Approach 1:
Rather than uniformly thickening the entire valve disc, the invention applies localized thickening only where structurally necessary (such as at the periphery or under the disc center) while keeping other areas thin. This selective approach maintains strength where needed while preserving streamlined flow characteristics in the main flow path, thereby reducing flow losses compared to uniform thickening
3Ease of manufacture
If conventional connections are used in valve construction, then assembly is simplified, but wear of connecting elements increases and torsional resistance of the shaft is weakened
Solution Approach 1:
The invention replaces conventional sharp-edged or grooved connections with rounded, curved connection surfaces between the valve disc and shaft. These curved connections eliminate stress concentration points (notch effects), reduce wear through smoother contact, and enhance torsional resistance by distributing forces more evenly across the connection interface, while still maintaining ease of assembly
Data Source
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AI summary
The invention relates to a fitting for shutting off or regulating a flowable medium, comprising the following features: - a housing (1) enclosing a flow channel (10); - a circular flap disc (2) pivotable about an axis of rotation (4) between the open position and the closed position; - viewed in an axial section, the cross-section of the flow channel widens in both directions from the plane of the axis of rotation of the flap disc; - viewed in an axial section and when the flap disc is in the closed position, its thickness increases in both directions from the plane of the axis of rotation.