IHEP-02 1.3 GHz 9-cell CavityR&D Status and Plan
The Third IHEP-KEK 1.3GHz SC Technology Collaboration MeetingDec. 7-8, 2010, IHEP, Beijing
GAO Jie, ZHAO Tongxian, ZHAI Jiyuan, LI Zhongquan, LI Dazhang, LIU ZhenchaoInstitute of High Energy Physics, Chinese Academy of Sciences
CHEN Jinzhe, QIAO JianqiangBeijing Hejieli Science and Technology Development Co. Ltd.
YUAN Hong, YU Huai, WANG JinxueBeijing Institute of Aviation Materials
OUTLINE
• Backgound of the IHEP 9-cell cavity
• IHEP-02 R&D goal and schedule
• IHEP-02 Fabrication Procedure
• HOM coupler
BACKGROUND
IHEP-01: Low-Loss Type 9-cell Cavity with Bare Tubes (VT) IHEP-02: Low-Loss Type 9-cell Cavity with Full End Groups (VT&HT)
IHEP-01 First Vertical Test Result Of IHEP-01
20MV/m (2010.07.01@KEK,STF)
IHEP-02 R&D GOAL, SCHEDULE
• IHEP-02 with full end groups for the horizontal test
• Achieve the requirement of ILC 25-35MV/m for the vertical test 20-31.5MV/m for the horizontal test
IHEP-02 2010-1011 2010 2011Fabrication 2010.06-2011.01 IHEP
Surface treatment 2011.02-03 IHEP
Vertical test 2011.04-06 Other Lab
weld helium vessel 2011.07 IHEP
assemble and HT 2011.08-12 IHEP
OUTLINE
• Backgound of the IHEP 9-cell cavity
• IHEP-02 R&D goal and schedule
• IHEP-02 Fabrication Procedure
• HOM coupler
Large Grain Niobium Sheets
The cavity material• disks from Ningxia OTIC (Nov., 2008)
• inspection, CP, annealing
• ultrasonic and eddy current scanning tests
• mechanical behavior sample test at room temp. and 4K• RRR measurement
• We do that when we made the IHEP-01
Nb sheets thickness measurement
The problem ： uneven thickness like the above sketch map(1) will lead to large crack, the Uniform thickness maybe good, but we think uneven thickness like the good cketch map(2) may be better.
1: NOT GOOD
2: GOOD
IHEP-02 Progress
Annealing @900OC, 3HoursHeating and cooling speed ： 300OC/H4: After annealing, we deep drawing the half cell again.
1: deep drawing 2: trimmingAfter trimming,Waiting for measurement
Some half cells3: Annealing after first trimming
Comparing of the twice deep drawing
37# 0.26 0.22 6# 0.33 0.11 1# 0.15 0.10 9# 0.22 0.17 15# 0.16 0.17 36# 0.14 0.05 11# 0.03 0.16 43# 0.22 0.10 17# 0.10 0.10 4# 0.19 0.09
Half cell No.
After the first deep drawing
After the second deep drawing
Standard deviation
IHEP-02 Progress
The half cells
Frequency measurement of the half cell
length, iris and equator diameter measurement
The measurement dataCell No. Freq. Q
MHz 7 1275.25 2300.00 4 1275.23 2000.00 36 1273.93 1900.00 33 1273.90 2000.00 20 1277.40 2200.00 17 1274.08 2100.00 15 1272.08 2000.00 34 1272.96 2090.00 6 1275.57 2150.00 9 1275.62 2350.00 11 1275.48 2800.00 1 1274.27 2100.00 42 1274.71 3000.00 13 1274.70 2700.00 43 1273.64 2900.00 19 1273.90 2900.00 37 1274.53 2200.00 35 1280.45 2400.00 8 1274.73 2900.00 18 1273.32 2680.00 2 1275.91 2700.00
Cell No.
Average/ mm
Standard
deviation/ mm
6 2.63 0.19 2 2.43 0.21 8 2.57 0.24
15 2.59 0.06 34 2.43 0.25 11 2.53 0.19 20 2.33 0.33 18 2.50 0.10 36 2.54 0.11 42 2.59 0.21 43 2.55 0.1613 2.13 0.26 4 2.62 0.16
35 2.52 0.35 19 2.59 0.11 9 2.47 0.21
17 2.64 0.09 1 2.61 0.20 7 2.42 0.20
33 2.55 0.10 37 2.60 0.12
Cell No.
Average/ mm
Standard deviation
/ mm6 60.47 0.23 2 60.25 0.17 8 60.28 0.24
15 60.55 0.05 34 60.28 0.25 11 60.62 0.25 20 60.56 0.14 18 60.53 0.15 36 60.29 0.15 42 60.40 0.27 43 60.74 0.23 13 60.60 0.24 4 60.43 0.24
35 60.24 0.15 19 60.49 0.16 9 60.52 0.12
17 60.35 0.22 1 60.39 0.23 7 60.64 0.19
33 60.51 0.15 37 60.30 0.04
Iris wall thickness
Iris diameter
Frequency of the half cell
IHEP-02 Progress Equator roundness reshaping 20 μm chemical polishing of half cells,
ultrasonic cleaning, rinsing, 3 μm chemical polishing at iris area, Rinsing,
EBW.
New Fixtures for cell equator roundness equator roundness reshaping
equator roundness reshaping result
37# 0.22 0.06 6# 0.11 0.06 1# 0.10 0.03 9# 0.17 0.04
15# 0.17 0.04 36# 0.05 0.03 11# 0.16 0.06 17# 0.10 0.05 4# 0.09 0.03
18# 0.04 0.04
No.
Before reshaping
after reshaping
Standard deviation
IHEP-02 Progress
Dumbell without stiffening ring Dumbell with stiffening ring
stiffening rings forming
stiffening rings forming
OUTLINE
• Backgound of the IHEP 9-cell cavity
• IHEP-02 R&D goal and schedule
• IHEP-02 Fabrication Procedure
• HOM coupler
IHEP-01 Mode; Freq. --- R/Q
Boundary conditions: Electric-Electric & Magnetic-Magnetic
IHEP 01 QE CALCULATION
TM010 ： 1.3GHz ， Qe2.88e+010 TE111 ： Freq. 1.6023GHz ， 1.6034GHz Qe: 4.24e+004 ， 7.85e+004
TM110 ： 1.87GHz ， Qe1.37e+004 TM011 ： 2.16GHz Qe ： 2.97e+004
CST M
odel
Lines per wavelength 55
Lower mesh limit 15
Mesh line ratio limit 10LL cavity with Tesla HOM coupler
HOM coupler material
Nb Stick RRR300 D60 ， L500 5 couplers housingNb sheet RRR300 200×150×8.8 6 Inner conductors
5 Tesla HOM couplers
IHEP-02 next plan
• HOM coupler fabrication will be speed up.
• End groups fabrication
• Cavity Welding
• IHEP-02 will be finished at early 2011
Summary
• The multi-cell cavity is one of the key components for 1.3 GHz SRF technology R&D of IHEP.
• We have developed effective methods, procedures, tools and facilities to fabricate and tune the 9-cell cavity.
• The IHEP-01 finished fabrication and EBW, surface treated at IHEP and tested at KEK STF in July 2010. 20MV/m. It will be test at kek again in early 2011.
• The IHEP-02 will finish in early 2011, surface treated at IHEP and test in middle 2011.
Thanks for your attention
