MHI#14 号機の２回目の EP2

1. MHI#14号機の２回目のEP2 Period : 2011/2/8 ~2/14 Process : CP @flanges, EP2(20μm) under low current density, Improved 1st Water Rinsing, Brushing @HOM & Flange using FM-20, Degreasing(FM-20, 2%) [1hour], Brushing @Flange, HPR x 2 [10 hours], Assembly in C.R., Vacuum evacuation, Leak check, Baking @100℃ (48hours) Preparation : Washing vacuum components with ultrasonic, Cleaning in C.R. Workers : M. Sawabe, Kirk, M. Satoh (KEK), K. Nakamura, N. Tasaki, F. Tsukada (Assist Engineering Co.), T. Okada (K-VAC), S. Imada (Nihon Advanced Technology) Process log Status of working Monitor data during EP & Rinsing process Comparison of EP2 STF Cavity Group Meeting @2011/2/14 Kirk

2. Condition of EP2 & Rinsing • EP acid (3/2のサンプルを使用) • Nb ingredient : 8.2g/ℓ • HF ingredient : 29 g/ℓ (全体38g/ℓの65%が反応に使われる) • Al ingredient : 15mg/ℓ • Current density : ～37mA/cm2 (最近の傾向より) • Cavity surface temperature : <35℃ • Control Voltage : 温度と電流密度を見ながら制御 • With normal N2 gas flow during extracting EP acid (8ℓ/min) • 1st water rinsing (1.5hours) • Improved version (25ℓ/minで20分間上下から流し続ける) • 1分毎に1秒間水抜きを繰り返す(40分間) • 最後の30分は10min (storing)/3min (flushing)で行う • Degreasing (1 hour) • FM-20(2%) • HPR (～10 hours) • 5h17m (6 turns, w/o blind flanges) • 4h25m (5 turns, w/ blind flanges) Brushing @HOM & Flange using FM-20 Brushing @Flange using FM-20 STF Cavity Group Meeting @2011/2/14

3. Process log ① 2/8 10:00 CP @flanges 10:30~ Attachment of jigs for EP 11:41 Set cavity to EP bed with crane 12:00 Installation of cathode bar to cavity Lunch time 13:00 Set data logger to cavity (totally 12ch) Leak check with N2 gas [O.K.] 13:30 Meeting for tomorrow’s working procedure 13:50~ Vacuum parts rinsing with ultrasonic in C.R. 14:40 Guide for Iwate-Ken Giren @STF 16:30 HPR Trouble occurred! Not finished at top position by automatic operation 17:00 fin. STF Cavity Group Meeting @2011/2/14

4. Process log ② 2/9 9:45 Cavity rotation starts / EP acid flow starts 9:56 EP2 starts 11:05 EP2 stops [1h09m00s] / Idling rotation (3 rpm / 20min) 11:10 Plastic case detachment 11:27 Idling rotation stops 11:29 EP acid is removed from cavity with N2 gas flow(0.020MPa) 11:42 First rinsing with ultra pure water starts 12:02 Flow rate of pure water is changed slightly due to low level 13:17 First rinsing with ultra pure water stops [1h30m] 13:24 Detachment of restriction jigs / Data logger detached 13:40 Un-installation of cathode bar from cavity / washing cathode bar 13:50 transferring cavity from EP bed to wagon / Checking inside cavity (No mark) 14:20 Detachment of jigs for EP / Detaching every blind flange / Checking inside cavity (No mark) [O.K.] 14:30 Brushing at every flange using FM-20 / Shower rinsing 14:40 Checking inside cavity (No mark) [O.K.] 14:42 Attachment of jigs for degreasing 14:47 Flowing FM-20 into cavity 14:54 Degreasing with ultrasonic starts 15:54 Degreasing with ultrasonic stops [1hour] 16:00 Removing FM-20 from cavity 16:05 Detachment of jigs for degreasing / Checking inside cavity (No mark) [O.K.] STF Cavity Group Meeting @2011/2/14

5. Process log ③ 2/9 16:10 Brushing at every flange using FM-20 / Shower rinsing 16:28 Transferring cavity from wagon on turntable for HPR using crane 16:38 Checking tolerance between position of nozzle and center of beam pipe 16:39 1st HPR for inside cavity starts 21:56 1st HPR for inside cavity stops [5h17m] (6 turns) 22:05 Attaching only top flanges in C.R. 22:26 fin. 2/10 9:00 Attachment of blind flanges at bottom beam pipe for 2nd HPR 9:18 HPR outside cavity with blind flanges starts [15mins] 9:36 2nd HPR for inside cavity with blind flanges starts 14:00 2nd HPR for inside cavity with blind flanges stops [4h25m] (5 turns) 14:05 Cavity enters into C.R. 14:30 Assembly in C.R. (Class 10) starts(type of helicoflex is changed from In to Sn coating) 15:35 Assembly in C.R. (Class 10) finishes / Moving out from Class10 to Class1000 15:44 Vacuum evacuation starts with heat guns 16:00 Turbo pump status 100% (Normal operation, but abnormal noise) 16:20 Leak check thoroughly @~1.5x10-3Pa [O.K.] 16:35 Baking @100℃ starts 19:00 Cavity vacuum : 1.58 x 10-4Pa @108℃/105℃/88℃/44℃ (Cell#3/Cell#7/Top/Bottom) Max Vacuum Level just after baking start : ~1.5 x 10-3Pa STF Cavity Group Meeting @2011/2/14

6. Process log ④ 2/12 16:45 Cavity vacuum : 1.23 x 10-5Pa @109℃/106℃/98℃/46℃ Ribbon heater at bottom beam pipe is broken! 16:50 Baking Off [48hours] / Ion Pump ON 17:15 Cavity vacuum : 1.43 x 10-6Pa @86℃/67℃/90℃/44℃ 2/14 8:52 Cavity vacuum : 1.01 x 10-7Pa / I.P head : 3.8 x 10-8Pa 9:25 MHI#14 goes out of clean room and moves to V.T.A. STF Cavity Group Meeting @2011/2/14

7. Status of working ① 電極棒の先端(ビニルテープで保護されている) STF Cavity Group Meeting @2011/2/14

8. Status of working ② EP後にブラシングをかける STF Cavity Group Meeting @2011/2/14

9. Status of working ③ 前回のEP2時に９セルに見られた白い縞模様は無くなっていた STF Cavity Group Meeting @2011/2/14

10. Status of 2nd EP2 for MHI#14 ① Tcavity voltage Treservoir current Troom Tcavity 平均電流密度が37mA/cm2程度になるように電圧を調整する。 (low current density EP) average current density STF Cavity Group Meeting @2011/2/14

11. Status of 2nd EP2 for MHI#14 ② 左図は平均電流密度と電圧の相関 右図は定常状態での分布 target STF Cavity Group Meeting @2011/2/14

12. 最近の定常状態の比較 今回は空洞内液温も電流密度もいずれも高かった。 ただし、電流の振れ幅はいつもよりは小さかった。 STF Cavity Group Meeting @2011/2/14

13. Status of 2nd EP2 for MHI#14 ③ EP2の間の空洞表面温度の状況。 #1 #2 #3 #4 #5 #6 #7 #8 #9 #10 #11 #12 STF Cavity Group Meeting @2011/2/14

14. Status of 2nd EP2 for MHI#14 ④ EP2の間の空洞表面温度の状況（前ページの最後の拡大図）。 #1 #2 #3 #4 #5 #6 #7 #8 #9 #10 #11 #12 STF Cavity Group Meeting @2011/2/14

15. Status of UWR for MHI#14 ① 通信不良でデータが途中で何度か跳んでいる。 #1 #2 #3 #4 #5 #6 #7 #8 #9 #10 #11 #12 STF Cavity Group Meeting @2011/2/14

16. Status of UWR for MHI#14 ② 一次洗浄中の空洞温度の状況（前ページの拡大図） #1 #2 #3 #4 #5 #6 #7 #8 #9 #10 #11 #12 STF Cavity Group Meeting @2011/2/14

17. Status of UWR for MHI#14 ③ ① ①は最初の注水完了時。 ②は流量を増やした状態での洗浄中。 ③は流量を減らした状態での洗浄中。 ② ③ STF Cavity Group Meeting @2011/2/14

18. Status of HPR for MHI#14 ノズルは1st HPRでは６往復、2nd HPRでも５往復させた。 ２回目の方がTOCは下がったが、particleが逆に上がっている。 STF Cavity Group Meeting @2011/2/14