 Process log  Status of working  Monitor data during EP & Rinsing process  Comparison of EP1 Period : 2012/2/23 ~ 2/27 Process : Degreasing (FM-20, 2%) [4hours], EP1(20μm, 50mA/cm 2 ), Normal 1 st Water Rinsing [60min], Degreasing (FM-20, 2%) [30min], HPR [1 hour] Preparation :Attachment to jigs Workers : M. Sawabe, Kirk (KEK), K. Nakamura, F. Tsukada, T Kitajima (Assist Engineering Co.), Kirk 1 STF Cavity Group MHI#15 号機の３回目の EP1

Degreasing (4 hours) FM-20 (2%) EP 液の汚染防止のため事前に行って汚れを落としておく EP acid (2/24 のサンプルを使用 ) Nb ingredient : 10.2g/ℓ HF ingredient : ? g/ℓ ( 全体 61.5g/ℓ の 65% が反応に使われる ) Al ingredient : ? mg/ℓ Current density : ～ 50mA/cm 2 (EP1 の時は通常の電流密度で行う ) Cavity surface temperature : <40 ℃ Control Voltage : 温度と電流密度を見ながら制御 Water mist blowing around upstream beampipe With normal N 2 gas flow during extracting EP acid (8ℓ/min) 1 st water rinsing (1 hour) 10min (storing)/3min (flushing) で行う Degreasing (30 min) FM-20 (2%) HPR (1 hour) 60min (4 turns, w/o blind flanges) 2 Condition of EP & Rinsing STF Cavity Group

Process log ① STF Cavity Group 3 2/22 9:00MHI#15 is moved to EP area 9:35Degreasing starts before EP1 13:35Degreasing finishes / Drying in CP area 2/23 9:00Attachment of jigs for EP 9:32Set cavity to EP bed with crane 9:47Installation of cathode bar to cavity [O.K.] 10:50EP preparation ready 10:55Meeting for tomorrow’s working procedure 12:00fin.

2/24 9:33Cavity rotation starts 9:38EP acid flow starts 9:57EP1 starts 11:02EP1 stops [1h05m] / Idling rotation (3 rpm / 20min) / Plastic case detachment 11:22Idling rotation stops EP acid is removed from cavity with N 2 gas flow(0.020MPa) 11:36First rinsing with ultra pure water starts 12:47First rinsing with ultra pure water stops [1h00m] Detachment of restriction jigs / Data logger detached 13:00Un-installation of cathode bar from cavity / washing cathode bar (Sulfur exists!) transferring cavity from EP bed to wagon Detachment of jigs for EP / Detaching every blind flange of teflon / Checking inside cavity (No mark) / Checking teflon surface (No mark) 13:35Shower area / Checking inside cavity (Sulfur smell) 14:00Degreasing starts (FM-20, 2%) [30min] 14:30Degreasing finishes 14:40Taking sample around beampipe 15:00Transferring cavity from wagon on turntable for HPR using crane 15:03Checking tolerance between position of nozzle and center of beam pipe 15:04HPR for inside cavity starts 16:08HPR for inside cavity stops [0h54m] 16:10fin 2/25 9:00move MHI#15 to inspection room Process log ② 4

STF Cavity Group Status of 3 rd EP1 for MHI#15 ① 5 current voltage T cavity T reservoir T room T cavity average current density EP1 の場合は通常通り 50mA/cm 2 で行う。 途中で１回ジャンプしているのは、 電圧を 20V 前後で調整していたことによる。

STF Cavity Group 6 Status of 3 rd EP1 for MHI#15 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

MHI#17 の EP1 の結果はドリフトの効果が大きい。 MHI#18 以降は EP 液が新しくなったため、振れ幅が大きい。 MHI#15 号機の３回目の EP1 はドリフトの効果が大きい。 最近の EP1 の定常状態の比較 Cavity Mean temp. [ ℃ ]R.M.S. temp. [ ℃ ] Mean i [mA/cm 2 ]R.M.S. i [mA/cm 2 ] MHI#14 1 st MHI#15 1 st MHI#16 1 st MHI#17 1 st MHI#14 2 nd EP 液交換 MHI#18 1 st MHI#19 1 st MHI#15 2 nd MHI#16 2 nd MHI#20 1 st TOS#2 1 st MHI#21 1 st MHI#22 1 st MHI#15 3 rd

Status of 3 rd EP1 for MHI#15 ③ STF Cavity Group 8 #1#2#3#4#5 #6#7#8#9#10 EP1 の間の空洞表面温度の状況。 #11 #12

Status of 3 rd EP1 for MHI#15 ④ STF Cavity Group 9 #1#2#3#4#5 #6#7#8#9#10 EP1 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 10 #1#2#3#4#5 #6#7#8#9#10#11 #12 Status of UWR for MHI#15 ①

STF Cavity Group 11 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 UWR for MHI#15 ②

Status of UWR for MHI#15 ③ STF Cavity Group 12

STF Cavity Group Status of HPR for MHI#15 13