Vacuum clamping technology specialists, Schmalz explain how the use of vacuum clamping technique can offer several advantages in aerospace component machining applications.
The aerospace sector is renowned for manufacturing excellence across all areas of the industry. There is a plethora of different components, some of which eventually come together to produce sub-assemblies such as airframe structures, and many of these individual parts, comprising a variety of material types, will have been precision machined in some way.
As for any manufacturing sector, maintaining the highest levels of productivity and efficiency are essential if delivery timescales and profitability targets are to be achieved. For machining applications this requires not only optimised tool paths when cutting, but also minimum set-up times during component changeover.
There are of course a number of factors which can influence part changeover and therefore non-productive machine time. The use of vacuum clamping technology however offers several advantages including the fact that the tooling is simpler, and finished machined parts can be replaced quickly and easily by just turning off the vacuum to release the finished part, and re-activating the vacuum circuit once the new part is in place. Vacuum clamping also provides greater access to more surfaces of the part, further optimising machining times as there are no mechanical clamps restricting the cutting path. Furthermore, components that may be difficult to clamp mechanically can be secured quickly and precisely, without fear of inducing distortion, when using a vacuum clamping system.
Schmalz Vacuum Automation unit offers a comprehensive range of solutions for machining applications within the aerospace sector, including individual components such as suction cups and vacuum generators, together with complete gripping systems and vacuum clamping solutions for holding workpieces in CNC machining centres.
Vacuum clamping technology offers a robust solution for a wide range of material types including aluminium and other nonferromagnetic materials such as CFK or plastics which are unsuitable for magnetic clamping systems. The concept of vacuum clamping is also suitable for a wide range of part sizes, from small individual components to large flat or contoured workpieces such as those which make up aerofoil surfaces.
Flexible vacuum clamping
The matrix plate, which provides the basis for a comprehensive and flexible vacuum clamping system, can be easily mounted onto a CNC machine table using either mechanical clamps or a zero-point clamping system. Also, multiple matrix plates can be connected if required to expand the clamping area for larger parts. The main body of the matrix plate is made of precision machined high-strength aluminium which facilitates distortion-free clamping of workpieces of varying sizes. Mechanical stops can be mounted on the side of the matrix plate enabling simple positioning of the workpiece and additional support to absorb transverse cutting forces.
Another vacuum clamping concept from Schmalz is the Innospann Steel-Plate System. This is a modular clamping system for precision metal and plastic machining which incorporates multiple vacuum openings. The Steel-Plate itself is mounted securely by vacuum to the Schmalz Matrix-Plate. Vacuum blocks, from the ISBL range, are then positioned as required above the vacuum openings and pre-located magnetically. Sealing magnets are used to cover any unused vacuum openings. All of the materials used in this system are specifically designed for use with cooling lubricants.
The ability to achieve the shortest possible set-up times, together with the flexibility to adapt to a wide range of workpiece geometries and material types, are key attributes of the technology. Whether in in low volume and high mix manufacturing environments or high volume areas, the benefits of vacuum clamping make a valuable contribution to achieving efficiency and productivity targets.