CLIC rf structure production G Riddone BERF 2009

CLIC rf structure production G. Riddone, BE-RF 2009. 02. 06 CLIC meeting, 20090206 1

Content • Structure production cycle and responsibilities • 30 GHz structures • X-band structures (CERN, KEK, SLAC) – From “mechanical design” to “ready for installation” • Master schedule • Conclusions CLIC meeting, 20090206 2

CERN structure production cycle and responsibilities RF design BE/RF Activities coordinated in mechanical design and production meetings Mechanical design BE/RF Tendering EN/MME BE/RF Decision point based on experimental results Fabrication EN/MME Preparation and Assembly TE/VAC, BE/RF CLIC meeting, 20090206 QC Dimensional control SEM EN/MME RF check BE/RF 3

KEK/SLAC structure production cycle and responsibilities RF design BE/RF Mechanical design KEK Tendering KEK Activities followed in monthly collaboration meetings Decision point based on experimental results Fabrication KEK Preparation and Assembly SLAC CLIC meeting, 20090206 QC KEK/SLAC 4

Status - 30 GHz ac. structures Ready for installation CLIC meeting, 20090206 Disks at CERN 5

Status – x-band ac. structures CLIC meeting, 20090206 6

CLIC vg 1/G structures CLIC meeting, 20090206 7

C 10 -CD 10 structures CLIC meeting, 20090206 8

Mechanical design RF INPUT ST Generated 3 D Parts RF CHECK Smar. Tea m CLIC meeting, 20090206 3 D Part Assembly Design 9 A. Samoshkin

Mechanical design CLIC meeting, 20090206 D. Gudkov 10

Damped Disks machining by turning and milling • Disks: machining by diamond turning • Adding damping features Needs milling (no circular symmetry) with smooth transition between milled and turned surfaces. • Assembly by vacuum brazing (CERN) • Assembly by H 2 brazing (KEK/SLAC) Accelerating structure CLIC G (undamped) Damped disks VG 1 CLIC meeting, 20090206 Firms: - VDL (fully qualified) - Kugler and LT Ultra (still under qualification) - KEK/SLAC firms 11

Achieved accuracy (disk) 30 GHz [accuracy in um] 11. 4 GHz [accuracy in um] Speed bump (VDL) Specified TD 18_disk (VDL) Specified Achieved SA: iris shape accuracy ID: inner diameter Ra: roughness Achieved OD: outer diameter Th: iris thickness S. Atieh CLIC meeting, 20090206 12

Achieved accuracy (T 18#2_KEK) T. Higo CLIC meeting, 20090206 13

Dimensional control (TD 18) TD 18 (VDL) 4 mm CLIC meeting, 20090206 14 From VDL dimensional report

Assembly by brazing Holes/grooves for brazing Before brazing After brazing , ready for RF check CLIC meeting, 20090206 15

Assembly by brazing SB, 813 ˚C, 20’ Tx 18: 815 ˚C, 20‘ 790 ˚C, 2 h CLIC meeting, 20090206 16

Assembly by bonding and alignment verification (SLAC) - Bonding of the disks - Brazing of the couplers - Brazing of the tuning studs 04. 12. 2008 17

Tuning by hammering Test set-up for tuning (SLAC) Disks with tuning studs CLIC meeting, 20090206 18

T 18_disk_CERN (1/3) Following the bad test results of the T 18_disk CERN a “Task Force” has been set-up to understand the cause and to define the actions for the future structures. History reconstruction and comparison to other structures have been made structure from Kugler with several NCs, cleaning procedure different from the old X-band structure, brazing design different from old X-band structure The structure was sent back to CERN last week. RF check, cutting and inspection (agreed procedure) will be then performed Corrective actions have been defined in case of confirmation of brazing problem CLIC meeting, 20090206 19

T 18_disk_CERN (2/3) - History Fabrication NC (ID, OD) Different than old x-band procedure 3 brazing cycles (low pressure, disk flatness) Mismatch output matching cell CLIC meeting, 20090206 20

T 18_disk_CERN 3/3 - Comparison CLIC meeting, 20090206 21

Updated at the monthly collaboration meetings CLIC meeting, 20090206 MASTER SCHEDULE (1/2) 22

MASTER SCHEDULE (2/2) CLIC meeting, 20090206 23

Future accelerating structures Name [#] Material Prototype Motivation Design Fabricated by Re-build a good structure C 10_vg 1. 35 2 Cu OFE Reference structure New CD 10_vg 1. 35_WDS (1. 16) 2 Cu OFE Brazing, tuning, leak tightness tests 5 disks Damping New CD 10_vg 1. 35_Choke 2 Cu OFE Brazing, tuning, leak tightness tests 5 disks New damping New CD 10 _vg 1. 32_WDS 2 Cu OFE Lower DT New C 10_vg 1. 35_milled 2 Cu OFE Milling vs turning New CD 10_vg 1. 35_WDS 2 Cu. Zr brazing tests on simple samples Harder material Existing CD 10_vg 1. 35_WDS 2 Glidcop brazing tests on simple samples Harder material Existing CD 10_vg 1. 35_WDS 2 Cu OFS brazing tests on simple samples Harder material Existing T 18_disk (SLAC/KEK) design Cu OFE TD 25_vg 1. 8_cc 2 Cu OFE (KEK)) Alternative solution KEK CLIC G damping material 2 Cu OFE Final design @ 12 GHz New 500 Ge. V – 502 WDS 2 Cu OFE Prototype New CLIC meeting, 20090206 PSI 24

Conclusions • Fabrication: at present VDL is the best firm, it is the only one which is fully reliable 8 -9 weeks for the TD 18 or TD 24 big effort to qualify new firms • T 18: waiting for cutting and inspection results • T 24: if the T 18 problem comes from brazing, machining of the disk can be done at CERN • TD 18: on hold until the problem on T 18 is fully understood (few iterations may be necessary) • T 24 - TD 24 (both at 11. 4 and 12 GHz) under fabrication • T 24 and TD 24 also made at KEK/SLAC • CD 10 structures: tendering for prototype disks • Decision to build at CERN T 18_disk with same design, Cu material and assembly methods as KEK/SLAC CLIC meeting, 20090206 25