MHI#14 号機の１回目の EP2  Process log  Status of working  Monitor data during EP & Rinsing process  Comparison of EP2 Period : 2011/1/11 ~ 1/17 Process : EP2(20μm) under low current density, Improved 1 st Water Rinsing, Degreasing(FM-20, 2%), HPR x 2, Assembly in C.R., Vacuum evacuation, Leak check, ℃ (48hours) Preparation : Washing vacuum components with ultrasonic, Cleaning in C.R. Workers : M. Sawabe, T. Shishido, Kirk, M. Satoh (KEK), K. Nakamura, N. Tasaki, F. Tsukada (Assist Engineering Co.), T. Okada, M. Iitake (K-VAC), M. Asano, T. Yanagimachi (Nihon Advanced Technology) Kirk 1 STF Cavity Group

2 EP acid (2010/12/21 のサンプルを使用 ) Nb ingredient : 6.6g/ℓ HF ingredient : 30g/ℓ ( 全体 46g/ℓ の 65% が反応に使われる ) Al ingredient : 12mg/ℓ Current density : ～ 37mA/cm 2 ( 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 N 2 gas flow during extracting EP acid (15ℓ/min) 1 st water rinsing (1.5hours) Improved version (25ℓ/min で 10 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 最後の 30 分は 10min (storing)/3min (flushing) で行う Degreasing (2 hours) FM-20(2%) HPR ( ～ 9 hours + 2.5hours) 4h25m (5 turns, w/o blind flanges) 4h25m (5 turns, w/ blind flanges) Condition of 1 st EP2 & Rinsing

Process log ① STF Cavity Group 3 1/11 9:00Mechanical polish for every flange 10:35~Attachment of jigs for EP 11:44Set cavity to EP bed with crane 11:53Installation of cathode bar to cavity 12:10Lunch time 13:00Set data logger to cavity (totally 12ch) 13:30Meeting for tomorrow’s working procedure 14:20Leak check with N 2 gas (Leak 14:30Check every sealing at rotary joint 15:17Leak check with N 2 gas again (never changed!) 15:20Take a rest 16:00Exchange both V-seals at rotary joints (No problem with eyes) White material on detached V-seal  Under analysis 16:35Leak check with N 2 gas [O.K.] 16:50fin... 14:10~Vacuum parts rinsing with ultrasonic in C.R.

Process log ② STF Cavity Group 4 1/12 9:30Plastic case attachment for cooling air Air cooling starts / below 10 surface 10:01EP2 starts 11:11EP2 stops [1h10m00s] / Idling rotation (3 rpm / 20min) 11:13Plastic case detachment 11:30Idling rotation stops 11:32EP acid is removed from cavity with N 2 gas flow(0.020MPa) 11:47First rinsing with ultra pure water starts 13:17First rinsing with ultra pure water stops [1h30m] 13:26Detachment of restriction jigs / Data logger detached 13:43Un-installation of cathode bar from cavity / washing cathode bar 13:49transferring cavity from EP bed to wagon / Checking inside cavity (No marks) 14:15Detachment of jigs for EP / Detaching every blind flange / adjusting degreaser / Checking inside cavity (white material observed at 9cell) / Black marks on Teflon flange 14:20Shower rinsing starts in CP room 14:31Attachment of jigs for degreasing 14:42Flowing FM-20 into cavity 14:47Degreasing with ultrasonic starts 16:47Degreasing with ultrasonic stops [2hours] 16:49Removing FM-20 from cavity 16:55Detachment of jigs for degreasing / Checking inside cavity (white material still exist)

Process log ③ STF Cavity Group 5 1/1217:18Transferring cavity from wagon on turntable for HPR using crane 17:19HPR for outside cavity starts [15mins] 17:33Checking tolerance between position of nozzle and center of beam pipe 17:341 st HPR for inside cavity starts 21:591 st HPR for inside cavity stops [4h25m] (5 turns) 22:04fin. 1/13 9:00Attachment of blind flanges at every port for 2 nd HPR 9:402 nd HPR for inside cavity with blind flanges starts 14:052 nd HPR for inside cavity with blind flanges stops [4h25m] (5 turns) 14:10Cavity enters into C.R. 14:40Assembly in C.R. (Class 10) starts (very careful assemble due to leak troubles) 16:30Assembly in C.R. (Class 10) stops 16:45Vacuum evacuation starts with heat guns 17:10Turbo pump ON (longer time than before!) 17:25Leak -3 Pa  Leak occurred from bottom flange (>>15N·m) 18:30Slow purging starts at ~100mℓ/min of Ar gas (over one night)

Process log ④ STF Cavity Group 6 1/14 9:00Slow purging finishes 9:50Exchange helicoflex for bottom flange in Class 10 helicoflex has some ploblems 10:30Pumping restarts / Leak check  Leak occurred again from bottom flange! helicoflex or bottom flange? 11:10MHI#14 goes out of clean room to do CP in EP area again 11:30Check bottom flange with eyes  No problem! white material disappears at 9cell! 11:40CP starts at every flange again 11:55CP finishes 12:05Check every flange -> No problem! 12:20Degreasing starts 13:20Degreasing stops [1hour] 13:50Set to turn table for HPR 13:56HPR for outside cavity starts [15mins] 14:183 rd HPR for inside cavity with blind flanges starts 16:423 rd HPR for inside cavity with blind flanges stops [2h24m] (3 turns) 16:50Cavity enters into C.R. 17:10Assembly in C.R. (Class 10) starts 18:30Assembly in C.R. (Class 10) stops 18:40Vacuum evacuation starts with heat guns / Turbo pump ON (1.0x10 -2 Pa) / Suddenly scroll pump breaks!! (>200Pa) / Re-connecting neighboring scroll pump

Process log ⑤ STF Cavity Group 7 1/1419:40Vacuum evacuation restarts using new scroll pump 20:05Leak check [O.K.] (1.0x Pa·m 3 /sec) ℃ starts 23:05Cavity vacuum : 3.05 x ℃ /104 ℃ /88 ℃ /90 ℃ (Max : ~1.12 x Pa) 1/1618:10Cavity vacuum : 2.40 x ℃ /104 ℃ /88 ℃ /90 ℃ 18:15Baking Off [45hours] / Ion Pump ON 1/17 9:00Cavity vacuum : 1.16 x Pa / I.P head : 5.1 x Pa 9:40MHI#14 goes out of clean room

Status of working ① STF Cavity Group 8

Status of working ② STF Cavity Group 9

Status of working ③ STF Cavity Group 10 一次洗浄の途中から水が漏れ出してい た （動画の方が分かりやすい）

Status of working ④ STF Cavity Group 11

Status of working ⑤ STF Cavity Group 12

Status of working ⑥ STF Cavity Group 13

STF Cavity Group Status of 1 st EP2 for MHI#14 ① 14 current voltage T cavity T reservoir T room T cavity average current density 平均電流密度が 37mA/cm 2 程度になる ように電圧を調整する。 (low current density EP)

STF Cavity Group Status of 1 st EP2 for MHI#14 ② 15 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

最近の定常状態の比較 STF Cavity Group 16 Cavity Mean temp. [ ℃ ]R.M.S. temp. [ ℃ ] Mean i [mA/cm 2 ]R.M.S. i [mA/cm 2 ] MHI#12 1 st MHI#13 1 st MHI#12 2 nd MHI#13 2 nd MHI#14 1 st

Status of 1 st EP2 for MHI#14 ③ STF Cavity Group 17 #1#2#3#4#5 #6#7#8#9#10 EP2 の間の空洞表面温度の状況。 #11 #12

Status of 1 st EP2 for MHI#14 ④ STF Cavity Group 18 #1#2#3#4#5 #6#7#8#9#10 EP2 の間の空洞表面温度の状況（前ページの最後の拡大図）。 #11 #12

STF Cavity Group 19 #1#2#3#4#5 #6#7#8#9#10#11 #12 Status of 1 st UWR for MHI#14 ①

STF Cavity Group 20 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 Status of 1 st UWR for MHI#14 ②

Status of 1 st UWR for MHI#14 ③ STF Cavity Group 21 最初と 2 回目のフラッシュで 液はほとんど無くなっている。

STF Cavity Group Status of HPR for MHI#14 22 ノズルは 1st HPR では５往復、 2nd HPR でも５往復させた。 ?