VAP® – Process
VAP® stands for Vacuum Assisted Process. The AIRBUS Defence & Space GmbH (formerly EADS) patented Vacuum Assisted Process (VAP®) uses the properties of modern, semi-permeable membrane systems in highly developed textile composites to apply the effect of a vacuum to the entire surface of a component. That way, trapped air and gas can be reliably and efficiently removed.
VAP® – Functional Principle
The Vacuum Assisted Process (VAP®) is a technique to manufacture composite parts using vacuum injection; it applies membrane-assisted low-pressure infiltration.
The surface of the part to be infiltrated with resin is covered with a flexible membrane system. The membrane is permeable to gas but impermeable to resin. When resin is infiltrated into the part inside the membrane, the latter keeps the resin inside the matrix and away from the vacuum duct. Yet, aided by the low pressure in the vacuum duct, trapped air and gas can still escape through the membrane’s micro-permeability and are purged via the textile layer. The vacuum acts uniformly, so purging takes place across the entire contact surface between part and membrane, during and after infiltration.
Schematic illustration of VAP® setup
VAP® – Benefits
- Easy implementation by usage of existing infusion tools and materials.
- Excellent quality of component without dry spots.
- Less re-work by reason of high grade of component quality.
- Low porosity in the laminate due to air and gas removal during and after infiltration.
- The required amount of resin can be calculation:
– fibre volume content is set exactly.
– less resin needed.
- Achievement of an homogeneous fibre volume content due to uniform vacuum across entire surface:
– no fluctuations and variation in component thickness.
– resin flow channels do not have to be planned in detail.
- Enables shorter cycle times based on faster infiltration process through a higher vacuum.
- High potential for integration.
- Consistently stable and controlled process.
- Provides high process reliability and reproducibility.
- Maximum economy especially compared to autoclave process.
- No/low initial investment needed.
Functional scheme of VAP®
VAP® – Patented from AIRBUS Defence & Space GmbH (formerly EADS) – German Patent DE 10013409 – Inventor: Stefan Utecht, Franz Stadler, Jürgen Filsinger, Torsten Lorenz