Composite Vessel Fitting Sealing Exposed End Grain
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Composite vessels used in aerospace applications face issues with through-wall penetrations, as they expose the end grain to internal fluids and external environments, leading to contamination and reduced strength, and existing sealing solutions lack positional accuracy and are not easily repairable.
Innovation Solution
A fitting system for composite vessels with through-wall penetrations that includes a sealing surface arrangement using O-ring seals and gland designs, providing improved positional accuracy and allowing non-destructive removal and re-installation, while protecting the end grain from exposure to fluids and contaminants.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If conventional machining processes are used to create through-wall penetrations, then positional accuracy is improved, but the end grain becomes exposed to fluid and environment
Solution Approach 1:
A fitting serves as an intermediary component between the machined penetration and the external environment. The fitting includes a sealing arrangement with seals that mate against the machined surface to prevent fluid and contaminant access to the end grain, while allowing the penetration to maintain its precisely machined dimensions and alignment.
Solution Approach 2:
The sealing function is extracted as a separate component (the fitting) rather than being integrated into the vessel wall itself. This allows the penetration to be purely structural and precision-machined, while the fitting provides the sealing protection against environmental harm to the end grain.
2Object-affected harmful factors
If molding process is used to cover end grain with resin rich layer, then protection from fluid exposure is achieved, but positional accuracy requirements are not met
Solution Approach 1:
The solution segments the protection function into a separate removable fitting rather than relying on the molding process to provide both structural integrity and sealing. This allows the penetration to be precisely positioned and sized for alignment with interface components, while the fitting provides the sealing protection.
Solution Approach 2:
The fitting acts as an intermediary that provides the sealing function without compromising the positional accuracy achieved through machining. The sealing arrangement within the fitting protects the end grain while allowing the penetration itself to maintain precise dimensions for proper alignment.
3Reliability
If bespoke gasket solutions are used for sealing, then sealing effectiveness is improved, but cost and repairability worsen
Solution Approach 1:
The fitting incorporates a sealing arrangement using conventional O-ring seals and gland designs that are universal and standard components. These standard seals can be easily replaced during maintenance without requiring specialized tools or procedures, improving repairability while maintaining effective sealing through proven designs.
Solution Approach 2:
The sealing components (O-rings, glands) are designed as relatively simple, replaceable elements that can be easily replaced if worn or damaged. This approach prioritizes ease of repair and cost-effectiveness over creating a permanent, non-serviceable sealing solution, allowing quick replacement of seals without replacing the entire fitting.
4Reliability
If fitting is made permanently attached to composite vessel, then sealing reliability is improved, but serviceability and repairability worsen
Solution Approach 1:
The fitting is designed with a dynamic, removable attachment method rather than permanent bonding. This allows the fitting to be securely attached during operation to maintain sealing reliability, but easily removed when service or repair is needed, providing adaptability between operational and maintenance states.
Solution Approach 2:
The fitting design allows for non-destructive removal and potential re-installation, enabling the sealing component to be recovered and reused if intact, or replaced if needed. This improves serviceability while maintaining sealing reliability during operational phases.
Data Source
AI summary
A composite vessel and fitting for a through-wall penetration having an exposed end grain. The fitting includes a sealing surface arrangement that seals against the composite vessel and prevents leakage of the vessel contents while protecting the end grain from exposure to internal fluid and/or external environment. The fitting includes an outer part, an inner part, and a through-wall part extending between the inner and outer parts across the penetration. An outer seal arrangement includes an outer seal having a first sealing surface that seals against the outer surface of the composite vessel to restrict environmental contaminants migrating to the end grain. An inner seal arrangement includes at least one inner seal having second and third sealing surfaces. The second sealing surface seals against the inner surface of the composite vessel and the third sealing surface seals a leak path or interface between the inner part and through-wall part to restrict internal fluid migrating to the end grain.