Paper |
Title |
Page |
TUPO036 |
Material for European XFEL Resonators |
460 |
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- W. Singer, S. Arnold, A. Brinkmann, J.A. Dammann, A. Ermakov, J. Iversen, D. Klinke, M. Lengkeit, W.-D. Möller, P. Poerschmann, X. Singer
DESY, Hamburg, Germany
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Twelve different types of semi-finished products will be provided by DESY to producers of European XFEL superconducting resonators. Work on material for XFEL cavities is divided into three phases (prototyping, pre-series and series production). Two new companies (Ningxia OTIC and Plansee Metal GmbH) have been qualified as XFEL suppliers. Material is contracted to 4 companies (Ningxia OTIC, Plansee Metal GmbH, Tokyo Denkai and W.C. Heraeus). Procurement of semi-finished products includes: acceptance on producer’s site, eddy current scanning of the sheets, testing for required parameters (RRR, interstitial impurity analysis, metallic impurities analysis, metallography, tensile test, hardness HV, dimensional check, surface roughness), documentation using the DESY EDM-System, marking, delivery to companies. Semi-finished products for pressure bearing sub-components of cavities have to be fabricated according Pressure Equipment Directive 97/23/EC. Qualification of material and the certification of the material producers were done by a “notified body”. Appropriate infrastructure and logistic for guiding through more than 20.000 of semi-finished products has been build up.
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Poster TUPO036 [2.332 MB]
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TUPO046 |
Results on Large Grain Nine-Cell Cavities at DESY: Gradients up to 45 MV/m after Electropolishing |
490 |
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- D. Reschke, S. Aderhold, A. Gössel, J. Iversen, S. Karstensen, D. Kostin, G. Kreps, A. Matheisen, W.-D. Möller, F. Schlander, W. Singer, X. Singer, N. Steinhau Kühl, A.A. Sulimov, K. Twarowski
DESY, Hamburg, Germany
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Since 2009 a series of eight nine-cell cavities (AC151 – AC158) of TESLA shape fabricated of large grain (LG) niobium material is under preparation and test at DESY. In a first step all cavities were tested after a BCP treatment. In a second step additional electro polishing is applied to all cavities. In this paper the treatment will be discussed and present results will be reported
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TUPO048 |
Commissioning and Upgrade of Automatic Cavity Tuning Machines for the European Xfel |
495 |
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- J.H. Thie, A. Gössel, J. Iversen, D. Klinke, G. Kreps, W.-D. Möller, C. Mueller, H.-B. Peters, A.A. Sulimov, D. Tischhauser
DESY, Hamburg, Germany
- D. Bhogadi, R.H. Carcagno, T.N. Khabiboulline, S. Kotelnikov, A. Makulski, R. Nehring, J.M. Nogiec, W. Schappert, C. Sylvester
Fermilab, Batavia, USA
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Four new tuning machines were developed and built in a collaborating effort among FNAL, KEK and DESY. Two machines were commissioned at DESY in a close teamwork with FNAL. For several months, these machines have been used regularly for the automatic tuning of different types of cavities for FLASH. Due to this operating experience and the requirements for the European XFEL cavity Specification, it was necessary to implement the following improvements: improve the precision of the eccentricity measurement; change the tuning sequence according to the different production stages in the cavity fabrication and preparation process; review and change the machine access procedures according to the safety aspects of the EC Directive of Machinery. These improvements required changes in both the mechanical parts developed by DESY and the electronics and software developed by FNAL. We report in detail about the commissioning, our tuning experience and the necessary improvements.
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Poster TUPO048 [0.257 MB]
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THPO053 |
Material for Fabrication of DESY Large Grain/Single Crystal Cavities |
854 |
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- X. Singer, J. Iversen, W. Singer, K. Twarowski
DESY, Hamburg, Germany
- H.G. Brokmeier
Technische Universität Clausthal, Institut für Nichtmetallische Werkstoffe, Clausthal-Zellerfeld, Germany
- R. Grill
Plansee Metall GmbH, Reutte, Austria
- F. Schölz, B. Spaniol
W.C. Heraeus GmbH, Materials Technology Dept., Hanau, Germany
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Material for large grain LG and single crystal SC cavities of TESLA shape has been developed in collaboration with industry. One of the aspects of LG material was electron beam melting of the ingots with required structure. The second was slicing of the discs cost effectively with tight thickness tolerances, high surface quality and high purity. Surface and structural properties of SC on the LG discs are investigated. Measurements of the crystal orientation on the LG discs of three companies have been done by complete penetration using synchrotron radiation. Two LG material features have been stressed in cavity production: the influence of the LG crystal orientation on the anisotropic behavior during deep drawing and the impact of pronounced steps at grain boundaries on cavity behavior. 11 LG 9-cell cavities of XFEL-like shape are fabricated. The procedure of increasing the crystal size by rolling of LG discs and cut out of SC discs, followed by subsequent forming and welding without destroying of the SC structure, was developed. A method of fabrication of single crystal cavities was proposed. Several SC cavities with different crystal orientations were produced.
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Poster THPO053 [2.201 MB]
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