Outer skin processing in aviation
In aerospace
weight is crucial
Every gram saved helps to reduce fuel consumption, improve aircraft efficiency and ultimately reduce CO2 emissions. That's why fuselage segments for aircraft and missiles, outer shells of turbines and other aluminum sheets are designed in a specific thickness profile according to their structural load. In stressed areas, higher plate thicknesses are used. In areas not subject to high stress, the sheets are reduced to lower residual thicknesses to save weight.
Within a stretch forming process, flat-rolled raw sheets are shaped into spherically curved plates. The subsequent manufacturing of the pockets and thus achievement of the defined residual wall thickness can be realized by various removal technologies.
Typical components machined to residual wall thickness:
- Fuselage part segments of airplanes and rockets
- Lipskins of turbines
- other aluminum sheet parts in aerospace quality
Conventional chemical milling
The previous procedure
A complex but still widely used process, for example, is chemical milling, in which sheets are immersed in chemical baths to obtain the desired thicknesses. While this technology is well controlled and established, it has enormous drawbacks due to the high use of chemicals and the relatively long process time.
DISADVANTAGES OF CHEMICAL MILLING:
- Long cycle times
- High use of chemicals
- Very high environmental impact
FOOKE offers an alternative to reduce environmental impact and shorten cycle times
Pros and cons
MECHANICAL MILLING CHEMICAL MILLING
+ Short cycle times - Long cycle times
+ State-of-the-art machine technology - High use of chemicals
reduces energy consumption
+ Green Technology - Low - Very high environmental impact
environmental impact
- Complex in terms of precision + Well controllable accuracy
35% PRODUCTIVITY INCREASE
compared to reference processes, through highly dynamic linear drive technology, optimum component clamping and intelligent quality control.
FOOKE
TURNKEY SOLUTION
Specially designed for mechanical thickness reduction of aircraft skins:
- 5-axis gantry milling machine
- Hardtooling
- Component measurement
- Compensation calculation
- Creation of serial milling process
The pre-shaped sheets are vacuum-fixed in negative contour - so-called hard tooling - and the pockets are machined by a high-speed machine. Not the depth of the pocket is critical here, but the particularly tight tolerance of the residual wall thickness.
The manufacture of large, precise and highly dynamic milling machines has been part of FOOKE's success story for decades. But it is the process of component measurement and compensation, based on various measuring methods, with the associated data processing and visualization, that can be highlighted as FOOKE's decisive core competence.


Ultrasonic probe and FOOKE data processing algorithm for
COMPONENT MEASUREMENT AND COMPENSATION
Various measuring routines and complex data processing algorithms for component correction ensure maximum accuracy. Deviations and e.g. deformations of the clamping device can be reliably detected and compensated. The application includes fully automatic integration of ultrasonic component measurement into the machine control. Temperature influences are also detected and taken into account accordingly in the machining process. Time-consuming adjustments to CNC programs are simply eliminated.
Strict and continuous quality control and documentation meet the extremely high requirements of the aerospace industry.
50% WEIGHT REDUCTION of a 10 x 2 m fuselage by pocket milling with a FOOKE turnkey solution.
This turnkey solution was developed, validated and has been in production at a large, well-known aircraft manufacturer in northern Germany since 2020.
INTELLIGENT MANUFACTURING IS THE KEY TO SUCCESS.
Use our know-how for your process.
Make an appointment for a consultation!
FOOKE has been supporting OEMs and suppliers from the aerospace industry with productive manufacturing processes for over 20 years. Would you like to learn how FOOKE can support your company in the production of fuselage or lipskin components?
Then call us at +49 2861 8009 - 222 or contact us by e-mail sales@fooke.de.
