With its 10’000 users – staff, researchers, colleagues from other institutes etc., the European Organisation for Nuclear Research CERN, which is headquartered in the canton of Geneva, Switzerland, is the largest research centre for particle physics in the world. At CERN, wide-ranging fundamental physics research activities are carried out with the help of a series of accelerators, including the LHC (Large Hadron Collider).
One of CERN’s very interesting research projects is the study of a new accelerator concept, the CLIC (Compact Linear Collider), an electron-positron machine 48.3 km long and with a centre-of-mass energy of up to 3 TeV. The new concept comprises a linear two-beam accelerator in which the counter-rotating beams interact at a designated collision point in the centre of the machine.
High precision machining
And this is where Kern Micro- und Feinwerktechnik comes into the picture. One of the key components for this project is a part manufactured by Kern: the PETS (Power Extraction and Transfer Structure), an 800 mm long copper rod made of highly conductive, oxygen-free copper with a high-precision, toothed comb profile. Eight of these copper rods (PETS) running parallel to one another are installed in an octagonal arrangement. An electron beam is then passed through this arrangement at the speed of light and some of the beam energy is extracted in the form of high-frequency microwaves. This power is then used for the acceleration process as such in a second parallel accelerator, with the copper surfaces being exposed to huge electromagnetic fields in the process.
To reach the very high precision needed, Kern offered its star performer – the Kern Pyramid Nano! Faced with this very demanding challenge, the machine’s key innovations come to the fore, i.e. its completely hydrostatic guides and drives. These run on a constantly controlled 15 µm thick hydraulic oil cushion. The Kern Pyramid Nano is one of the very few milling machines in the world on which the workpiece is not moved by mechanical components. Positioning accuracy is only possible if the friction is equivalent to zero – as is the case with the Kern Pyramid Nano.
We will detail this success story in one of our next issues.