Intermediate Layer Raised Features Aircraft Joint Sealing
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current methods for forming sealed structural joints in aircraft components require multiple disassembly steps, leading to increased process time and potential for errors, as well as the risk of unintended mixing of uncured sealant with liquid shim.
Innovation Solution
A method involving an intermediate layer with raised structural features is applied between the faying surfaces of aircraft components, allowing for a continuous seal and load path upon assembly, reducing the need for multiple disassembly steps and preventing mixing of sealant and liquid shim, with the option for the intermediate layer to be continuous or permeable for improved bonding.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If multiple disassembly steps are used for cleaning, de-burring and sealant application, then manufacturing precision and reliability are improved, but productivity is reduced and process time increases
Solution Approach 1:
The intermediate layer with raised features is applied in advance to the second component before final assembly. This preliminary action ensures that the sealant application area is pre-defined and protected, eliminating the need for multiple disassembly steps for cleaning and preparation while maintaining sealing quality.
Solution Approach 2:
The intermediate layer acts as a mediator between the sealant and liquid shim. It provides a structured interface that guides sealant placement and prevents unintended mixing with the liquid shim, thereby maintaining manufacturing precision without requiring repeated disassembly operations.
2Manufacturing precision
If multiple disassembly steps are performed, then manufacturing precision is improved, but loss of time increases
Solution Approach 1:
The intermediate layer is prepared in advance on the second component, including the raised structural features that define the sealant application area. This preliminary preparation eliminates the need for time-consuming disassembly and reassembly cycles while ensuring precise sealant placement and joint assembly.
3Ease of manufacture
If sealant and liquid shim are applied directly to faying surfaces, then ease of manufacture is improved, but reliability is reduced due to unintended mixing
Solution Approach 1:
The intermediate layer with raised features serves as a physical barrier and guide between the sealant and liquid shim. It allows both materials to be applied to the assembly in a single operation while preventing their unintended mixing, thereby maintaining both ease of manufacture and reliability.
Solution Approach 2:
The intermediate layer provides locally differentiated functionality: the raised features create specific zones where sealant is contained and directed, while other areas remain available for liquid shim application. This local quality differentiation ensures proper material placement without complex application procedures.
4Reliability
If a continuous intermediate layer is used, then reliability is improved by preventing material mixing, but device complexity increases
Solution Approach 1:
The intermediate layer is segmented into raised structural features rather than being a solid continuous barrier. This segmentation maintains reliability by providing sufficient separation and guidance for sealant and liquid shim while reducing the overall complexity and material requirements compared to a fully continuous layer.
5Ease of manufacture
If the intermediate layer is made permeable, then ease of manufacture is improved with better bonding, but reliability may be reduced due to potential material passage
Solution Approach 1:
The intermediate layer exhibits local quality variations through its raised features: the peaks provide containment and guidance for preventing material mixing, while the valleys or permeable regions allow for controlled interaction and bonding between sealant, liquid shim, and the component surfaces. This local differentiation achieves both ease of manufacture with good bonding and reliable material separation.
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 approach significantly reduces the process time and minimizes errors by enabling 'one-way assembly' and preventing unintended mixing, while ensuring a sealed and structurally sound joint with improved bonding capabilities.
Implementation Method 1
The liquid shim cures in place in the joint and the composition is optimised for compression and fatigue properties
Implementation Method 2
said series of raised structural features being positioned to allow the sealant to extend across the joint between said raised features and form a continuous seal across the joint face
Implementation Method 3
the method of the invention thus allows a continuous load path through the joint from the first component through the series of raised structural features to the solidified shim and thence to the second component
Data Source
AI summary
A method of producing a sealed structural joint between two components (23, 24) and such a sealed joint are provided. The method includes the steps of applying a layer of sealant (27) to the first component (23), applying liquid shim (28) to the second component (24), inserting an intermediate layer (29) between the sealant (27) and the liquid shim (28), the intermediate layer (29) having a series of raised structural features (31) to engage the first component (23). The features (31) are positioned to allow the sealant (27) to extend across the joint between the raised features (31) to form a continuous seal. The joint is then closed and cure of the liquid shim (28) and sealant (27) takes place to solidify the shim (28) to the desired thickness within the joint.