DESY, Hamburg
The main RF-Couplers for 1.3GHz TESLA-Type cavities in the FLASH linac need several preparation and processing steps. The RF processing is usually done on coupler test stands (2 couplers pairwise), on a single coupler together with a superconducting cavity in the horizontal cavity test stand, on the module test stand (up to 8 cavities) or finally in FLASH. In FLASH one or more modules are connected to one klystron and conditioned together. Therefore the software was forked several times and merged during the last FLASH shutdown into one version. This is flexible enough to handle all these different test setups, without additional programming for IO hardware or data handling. The system is based on LabView, DOOCS and Linux operating system. The working principle is shown, including a possible outlook for the XFEL cavity production and operation.
DESY, Hamburg
For the series production of XFEL cryo modules, it is planned to test all complete modules prior the installation in the XFEL tunnel. For the test stands in the Accelerator Module Test Facility (AMTF), we have developed a new technical interlock. The interlock allows the observation of 8 individual analog signals per device (like temperature, pressure, light, free electrons) and can be fully remote controlled. Each channel has its own upper and lower remote controlled thresholds. The channels will be customized with sensor specific module cards, which adapt the power needs and signal conditioning to the specifications of the different sensors. The local display is used as user interface and the little space requirement makes the device quite suitable. An overview of functionality, internal features, connectivity and extendability of the device is given.
DESY, Hamburg
Radio frequency measurements on parts and subassemblies of superconducting cavities during its fabrication are a proper method of quality management and quality assurance. During the fabrication of 1.3 GHz cavities for FLASH, a simple device was used for measuring the half cells, dumb bells and endgroups. Because of the long test duration the device is not applicable for massproduction of 800 cavities. A semiautomated RF measurement machine was designed and built. This machine performs an easy load of the parts, consistent RF contacts, automated RF measurements and documentation. We describe the functionality of the RF-measurement machine and performance of the prototype during fabrication of 40 cavities for FLASH.
DESY, Hamburg
Fermilab, Batavia
A semi-automatic cavity tuning machine is used at DESY since 15 years to tune the field flatness and concentricity of the TESLA shape 9 cell cavities for FLASH. Based on this experience a further development work was done in a collaboration effort among FNAL, DESY and KEK to support the high throughput cavity fabrication necessary for the European XFEL and other SRF based future projects. Two of the four machines will be delivered to and operated by the cavity vendors for the tuning of the XFEL cavities. We describe the mechanical design and functionality of these machines and discuss the safety aspects for the operation at the industry.