Revamping and extension of the existing HERA refrigeration plant for the operation of the European XFEL linac at DESY in Hamburg, Germany.

In line with the European XFEL Project which is being implemented in the metropolitan region of Hamburg, in close collaboration with DESY in Hamburg, we have been awarded with the contract to revamp, modify and extend the HERA helium refrigeration plant. This turn-key project comprises besides the engineering, design and delivery of 2 new valve and cold compressor boxes also the site management, installation and commissioning with acceptance test run.

DESY is one of the world’s leading accelerator centres and a member of the Helmholtz Association. DESY develops, builds and operates large particle accelerators used to investigate the structure of matter.

DESY is closely involved in a number of major international projects, including the X-ray laser European-XFEL in Hamburg and Schleswig-Holstein, the Large Hadron Collider LHC in Geneva, the neutrino telescope IceCube at the South Pole and the International Linear Collider ILC.
The European-XFEL will generate ultrashort X-ray flashes – 27 000 times per second and with a brilliance that is a billion times higher than that of the best conventional X-ray radiation sources. The outstanding characteristics of the facility are unique worldwide. Starting in 2015, it will open up completely new research opportunities for scientists and industrial users. For more information about the European-XFEL www.xfel.eu

Right: Special magnet arrangements (“undulators”), in which the electrons on a slalom course emit laser-like radiation; image source: DESY
For the planed extension of the HERA refrigeration system Linde Kryotechnik will do a general overhauling of the existing compressor units. This includes the dismantling and revision of the compressors at the manufacturer’s workshops. Besides the warm machines two of the HERA cold boxes will be opened and modifications at the internal piping will be performed. The expansion turbines are examined and revamped at the workshop of Linde Kryotechnik.

For providing the 2K refrigeration capacity one additional valve box and one cold compressor box will be delivered. The valve box will be installed in the HERA refrigeration hall whereas the cold compressor box will be located in the tunnel of the new XFEL linac. The cold compressor box is equipped with 4 cold compressors placed in series in order to achieve the required sub-atmospheric environment for the 2K sub-cooling of the helium gas.
The refrigeration capacities of this new configured helium refrigeration plant for the XFEL linac are between 24kW @ 80K and 1.8kW @ 2K.
The plant hand-over to the customer is planed to take place in the first half of 2014.
This project is another important milestone for Linde Kryotechnik in the long lasting successful co-operation with DESY.