Multilayer Pressure Vessel Joining Structure to Prevent Layer Gaps

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing pressure vessels experience gap formation between layers due to differing coefficients of thermal expansion and material choices, leading to potential defects and instability during temperature changes and manufacturing.

Innovation Solution

Introduce an adhesive layer between the layers of the pressure vessel, particularly at interfaces with inlet or centering bodies, to compensate for forces and prevent gap formation, using materials like epoxy resin and carbon fiber reinforced plastic (CFRP) with adhesive properties.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Adaptability or versatility

If different materials (plastics, metals, composite materials) are used for inner container, boss, and outer container, then the pressure vessel can be optimized for specific functions (sealing, pressure stability, shock resistance), but gap formation occurs between layers due to different coefficients of thermal expansion

Engineering Contradiction:
Improvefunctional optimizationVSAvoidgap formation
Core Design Contradiction:
Adaptability or versatilityVSStability of the object's composition

Solution Approach 1:

An adhesive layer is introduced as an intermediary substance between the inner container and outer container layers. This adhesive layer compensates for the different coefficients of thermal expansion by providing a compliant bonding interface that can accommodate dimensional changes without creating gaps, while still maintaining strong structural attachment between the dissimilar materials.

Inventive Principle:
Principle #24Intermediary (Mediator)

Solution Approach 2:

The adhesive layer changes the physical and chemical parameters of the interface between layers. By selecting adhesives with specific properties (viscosity, curing characteristics, thermal expansion coefficients), the bonding interface can be optimized to accommodate thermal cycling and prevent gap formation while maintaining the functional advantages of different materials.

Inventive Principle:
Principle #35Parameter changes

2Reliability

If adhesive is applied to bind layers together, then gap formation is prevented and structural integrity is enhanced, but the complexity of the manufacturing process increases

Engineering Contradiction:
Improvestructural integrityVSAvoidmanufacturing process complexity
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The adhesive is applied in advance to the bonding surfaces before final assembly of the pressure vessel layers. This preliminary application ensures that the adhesive is properly distributed and positioned, reducing the need for complex adjustment procedures during assembly and simplifying the overall manufacturing process while ensuring reliable bonding.

Inventive Principle:
Principle #10Preliminary action

3Stability of the object's composition

If adhesive layer thickness is increased to compensate for forces and prevent gaps, then gap prevention is improved, but the volume and weight of the pressure vessel increase

Engineering Contradiction:
Improvegap preventionVSAvoidpressure vessel volume
Core Design Contradiction:
Stability of the object's compositionVSVolume of moving object

Solution Approach 1:

The adhesive layer is applied selectively at specific locations where gap formation is most likely to occur, such as at the interfaces between layers and at the boss connections. This localized application provides effective gap prevention and force compensation at critical areas without unnecessarily increasing the overall volume and weight of the pressure vessel through uniform thick adhesive coverage.

Inventive Principle:
Principle #3Local quality

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 adhesive layer effectively binds the layers together, preventing gaps and reducing stress concentrations, enhancing structural integrity and thermal insulation while minimizing relative movements.

Implementation Method 1

an joining agent is introduced between at least two layers of the pressure vessel in at least one planar area, which forms a further layer and compensates for forces occurring between the at least two layers of the pressure vessel within this further layer and prevents the formation of gaps

Methodology Applied
Scientific EffectAdhesive bonding: Adhesive

Implementation Method 2

the outer container is spaced apart from the inner container and a vacuum is maintained in the space between them for thermal insulation. Additionally, the inner container is surrounded on its outer surface by an insulating layer.

Methodology Applied
Scientific EffectThermal insulation: Thermal Insulation

Data Source

PatentEP3630470B1Robust high-pressure container structure having joining means
Publication Date: 2026.01.07 AUDI AG
  • EP3630470B1 patent drawingFigure 1
  • EP3630470B1 patent drawingFigure 2
  • EP3630470B1 patent drawingFigure 3~4

AI summary

The invention relates to a method for producing a pressure container (100) having multiple layers and comprising a cylindrical central part with two curved side parts, wherein at least one side part has a filling opening (108), characterised in that a joining means is introduced between at least two layers (216, 218) of the pressure container (100) in at least one flat region, which joining means forms a further layer (224, 230) and compensates for forces occurring between the at least two layers (224, 230) of the pressure container (100) within this further layer (224, 230), and prevents the formation of a gap in this at least one flat region.