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Kickoff: Series production of the bypass lines for the large FAIR ring accelerator begins

Photo: G. Otto/GSI

Bypass segment

Photo: J. Polinski/WUST

Visit in Poland



Extreme cold in one area, warm room temperature right next to it – the sophisticated cryotechnology for the large SIS100 ring accelerator, the heart of the international accelerator facility FAIR, is a major challenge. An important element in achieving the best possible technical solutions for cooling the 1100-metre-long SIS100 is now going into series production: the so-called bypass lines, a Polish contribution to the FAIR facility currently under construction at the GSI Helmholtzzentrum für Schwerionenforschung.

Recently, a delegation with Jörg Blaurock, Technical Managing Director of GSI and FAIR, and representatives of the FAIR project lead as well as the subprojects ring accelerator SIS100/SIS18 and fragment separator Super-FRS visited the Wroclaw University for Science and Technology (WUST) in Poland. The delegation, which also included subproject managers Peter Spiller (SIS100/SIS18) and Haik Simon (Super-FRS) as well as work package managers Thomas Eisel and Felix Wamers, met with representatives of the Polish FAIR shareholder, the University of Wroclaw, to which Majka Zbigniew belonged, as well as the top management of the executing Wroclaw company Kriosystem. The kickoff meeting marked the start of the important phase of series production of bypass lines for the SIS100.

The bypass lines that are arranged around the entire ring ensure the transport of the cryogenic agent (liquid helium, LHe) past warmer accelerator components such as high-frequency systems, injection systems or extraction systems and serve to bypass these room-temperature devices in the straight sections of the SIS100. In this way, they constantly guarantee the cold of -268.6 °C required for the operation of the superconducting magnets in the entire ring system and are thus an essential part of the SIS100 local cryogenics system.

Beside the LHe process lines, the bypass lines contain the most important magnet bus bar system (consisting of three quadrupole- and one dipole circuit). In comparison to standard LHe transfer lines, they create major technical challenges. According to a design of WUST University, which was responsible for the design, Kriosystem has already manufactured and delivered the first of a series (FoS, First of Series) of bypass lines, which was successfully tested and accepted at GSI in Darmstadt after careful SAT tests (Site Acceptance Tests). With the signed manufacturing contract between the provider WUST and the company Kriosystem, the series production of 27 such bypass lines will now be launched.

In addition to these bypass lines, two more major technical systems of the highly specialized SIS100 cryogenics will be designed and manufactured as a Polish inkind contribution: The "lead boxes", chambers with terminals for feeding electricity into the cryogenic system, provide the link between the room-temperature water-cooled copper cables and the superconducting Nuclotron cables of the cryomagnetic system. The inkind contract for these lead boxes has already been signed and the design could meanwhile be completed. For the so-called "feed boxes" the content of the inkind contract has already been agreed and the final signature process has been launched.

Another important Polish FAIR contribution is planned for the superconducting fragment separator (Super-FRS) for the local cryogenics system. In order to be able to sign the corresponding inkind contract on short term, a steering group has been established to finalize the definition of the contractual scope of this contribution and to implement technical simplifications, proposed by the responsible team at WUST and GSI. (BP)

Bypass segment
Visit in Poland
The first of the bypass lines (FoS, First of Series) has already been successfully tested in the test facility on the GSI and FAIR campus.
The GSI and FAIR delegation at company Kriosystem in Wroclaw Poland.
Photo: G. Otto/GSI
Photo: J. Polinski/WUST