SRF2011 - List of Authors (Steinhau-Kuehl, N.)

Paper	Title	Page
TUPO018	Update of the DESY Infrastructure for Cavity Preparation	401
	M. Schalwat, K. Escherich, N. Krupka, A. Matheisen, B. Petersen, N. Steinhau Kühl DESY, Hamburg, Germany
	The clean room is the main infrastructure for preparation of superconducting cavities at DESY, which was set up in the early 90th of the last century. This clean room was completely renovated in 2009. The ground plan of clean room class ISO 4 was enlarged from 20 to 53 m² and the areas of ISO 7 of the old clean room were upgraded to ISO 6 and ISO 5 standard. Areas for ultrasonic cleaning, ultrapure water rinsing and chemical surface treatment were upgraded to ISO 4 standards. Multiple vacuum connections were installed to reduce movement of cavities. A 120oC heating chamber was connected to the ISO 4 assembly area and allows the in situ bake out of multi cell super conducting resonators. For industrial cavity production it was shown that a high pressure rinsing unit driven by a turbine pump allows feeding several high pressure rinsing stands in parallel. For cost reduction of ultra pure water production and for increase of the amount of water in the cavity preparation cycle, a recirculation of rinsing water is under commissioning. Fixtures and tools for the assembly of the Beam position monitor and Quadrupol units (BQU) for the XFEL modules are installed and commissioned.

TUPO041	Investigation on Cavity String Assembly and Repair	472
	A. Matheisen, B. Horst, van der, S. Saegebarth, P. Schilling, M. Schmökel, N. Steinhau Kühl, H. Weitkämper DESY, Hamburg, Germany
	At DESY several cavity strings for modules of the FLASH accelerator and studies on XFEL prototypes are completed. In some modules cavities have been exchanged for upgrade of applicable module gradients or exchange of resonators showing performance degradation in the module test. Assembly and repair sequences and quality control plans for cavity string are developed and applied. From module string PXFEL3 six out of eight cavities are removed and handed over to CEA Saclay for training of string and module assembly. On two of these cavities the procedures for assembly and exchange of cavities in cavity strings are crosschecked. These cavities are tested at 2 K as removed from string without additional treatments to cross check assembly and repair sequences.

TUPO046	Results on Large Grain Nine-Cell Cavities at DESY: Gradients up to 45 MV/m after Electropolishing	490
	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
	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

Paper

Title

Page

Update of the DESY Infrastructure for Cavity Preparation

401

M. Schalwat, K. Escherich, N. Krupka, A. Matheisen, B. Petersen, N. Steinhau Kühl
DESY, Hamburg, Germany

The clean room is the main infrastructure for preparation of superconducting cavities at DESY, which was set up in the early 90th of the last century. This clean room was completely renovated in 2009. The ground plan of clean room class ISO 4 was enlarged from 20 to 53 m² and the areas of ISO 7 of the old clean room were upgraded to ISO 6 and ISO 5 standard. Areas for ultrasonic cleaning, ultrapure water rinsing and chemical surface treatment were upgraded to ISO 4 standards. Multiple vacuum connections were installed to reduce movement of cavities. A 120oC heating chamber was connected to the ISO 4 assembly area and allows the in situ bake out of multi cell super conducting resonators. For industrial cavity production it was shown that a high pressure rinsing unit driven by a turbine pump allows feeding several high pressure rinsing stands in parallel. For cost reduction of ultra pure water production and for increase of the amount of water in the cavity preparation cycle, a recirculation of rinsing water is under commissioning. Fixtures and tools for the assembly of the Beam position monitor and Quadrupol units (BQU) for the XFEL modules are installed and commissioned.

TUPO041

Investigation on Cavity String Assembly and Repair

472

A. Matheisen, B. Horst, van der, S. Saegebarth, P. Schilling, M. Schmökel, N. Steinhau Kühl, H. Weitkämper
DESY, Hamburg, Germany

At DESY several cavity strings for modules of the FLASH accelerator and studies on XFEL prototypes are completed. In some modules cavities have been exchanged for upgrade of applicable module gradients or exchange of resonators showing performance degradation in the module test. Assembly and repair sequences and quality control plans for cavity string are developed and applied. From module string PXFEL3 six out of eight cavities are removed and handed over to CEA Saclay for training of string and module assembly. On two of these cavities the procedures for assembly and exchange of cavities in cavity strings are crosschecked. These cavities are tested at 2 K as removed from string without additional treatments to cross check assembly and repair sequences.

TUPO046

Results on Large Grain Nine-Cell Cavities at DESY: Gradients up to 45 MV/m after Electropolishing

490

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

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