[Aidan]
I've attached a timeline of our inspection this afternoon along with today's pumping timeline,
Here is a brief summary of observations from previous pumping timelines. Today's pump down is consistent with previously observed timelines.
2:17PM – Assessing the impact of the 408K event in the MegaStat
Coldhead reached 363K (90C)
Innershield reached 403K (130C)
2:24PM – Aquadag E service temperature (149C)
https://www.laddresearch.com/index.php/lanotattachments/download/file/id/40/store/1/
Maximum service temperature in air* : 300°F (149°C)
*Service temperature under vacuum conditions is significantly higher. Contact Acheson for specifics.
2:25PM – Bringing Megastat back up to air for initial inspection
2:37PM – chamber is at air
2:41PM – removing bolts
3:13PM – initial inspection looks normal. No elevated amount of black particulates found on surfaces – consistent with or less than the amount seen last time we opened.
Stephen detected faint smell different from last time (“campfire”?)
- One RTD connector did delaminate Aquadag from the inner shield
3:14PM - Stephen reattaching the RTD wiring that had delaminated. I wiped up visible particulates with isoproponal soaked wipe.
3:21PM – putting lid back on
3:30PM – lid on. Screws in finger tight
3:35PM – screws tight – ready to pump
3:40PM – pumping station on
Time (minutes) |
Pressure (Torr) |
Notes |
0 |
7.5E2 |
Pirani gauge initially |
1 |
7.5E2 |
|
2 |
7.5E2 |
|
4 |
7.5E2 |
|
5 |
7.5E2 |
|
7 |
7.5E2 |
|
9 |
7.5E2 |
|
10 |
7.5E2 |
|
11 |
7.5E2 |
|
12 |
4.3E2 |
Gauge starts reading decrease |
13 |
2.2E2 |
|
14 |
9.8E1 |
|
15 |
5.5E1 |
Turbo ON |
16 |
2.9E1 |
|
17 |
1.6E1 |
Turbo at 44% |
18 |
9.4E0 |
|
19 |
4.9E0 |
|
20 |
1.8E0 |
Turbo at 58% |
21 |
3E-2 |
Turbo at 70% |
22 |
1.1E-3 |
ION gauge readings from here. Turbo at 91% |
23 |
7.5E-4 |
Turbo at 100% |
24 |
6.3E-4 |
|
25 |
5.9E-4 |
|
26 |
5.5E-4 |
(Cryo-cooler normally turned on around this time)
Not in this instance though
|
27 |
5.0E-4 |
|
28 |
4.59E-4 |
|
29 |
4.26E-4 |
|
30 |
4.05E-4 |
|
|
|
|
|