Difference between revisions of "Minutes-8-9-2012"
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Participants: Bill, Dave, Chris, Nick, Vlad, Eugene, and Lubomir | Participants: Bill, Dave, Chris, Nick, Vlad, Eugene, and Lubomir | ||
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== Cathode corrosion == | == Cathode corrosion == | ||
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- Lubomir: a test with cathode foils, Viton/EPDM O-rings and water was done (at Blue Crab dirty area). First, the O-ring samples were pressed against the foils with a lead brick, also using G10 and aluminum plates to equalize the pressure. After a couple of days, water (from the tab) was put on the samples. Corrosion appeared immediately on the next day: very well pronounced on the EPDM sample and resembling the same dark traces that we had on the cathodes of the first and second packages (see first picture above), also some corrosion but with lighter color on the Viton sample. Olga did SEM analyses on the two sample foils at the places of the O-rings: second link above. Generally, the experiment was not done in a clean environment and tab water was used, so you see a lot of dirty stuff like chlorine. At the same time sulfur is visible in almost all the areas of the EPDM sample, while for the Viton sample sulfur is present in much smaller areas visible with high magnification. We started the same experiment inside the clean room using distilled water; expect results next week. | - Lubomir: a test with cathode foils, Viton/EPDM O-rings and water was done (at Blue Crab dirty area). First, the O-ring samples were pressed against the foils with a lead brick, also using G10 and aluminum plates to equalize the pressure. After a couple of days, water (from the tab) was put on the samples. Corrosion appeared immediately on the next day: very well pronounced on the EPDM sample and resembling the same dark traces that we had on the cathodes of the first and second packages (see first picture above), also some corrosion but with lighter color on the Viton sample. Olga did SEM analyses on the two sample foils at the places of the O-rings: second link above. Generally, the experiment was not done in a clean environment and tab water was used, so you see a lot of dirty stuff like chlorine. At the same time sulfur is visible in almost all the areas of the EPDM sample, while for the Viton sample sulfur is present in much smaller areas visible with high magnification. We started the same experiment inside the clean room using distilled water; expect results next week. | ||
| − | - Three other test experiments are running. One with production cathodes and a wire frame that started more than two weeks ago. Second one with the small-scale prototype | + | - Three other test experiments are running. One with production cathodes and a wire frame that started more than two weeks ago. Second one with similar samples using the small-scale prototype, running since yesterday when we were able to fix the HV. The third one is the Vlad's experiment using the vacuum chamber (picture linked) with same samples (EPDM, Viton with/without Apiezon) with same gas, but no HV, with some water inside to create moisture and heated with a lamp (only during the day) up to 80degC. We will open it on Monday. |
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== Production == | == Production == | ||
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- Dave showed the latest Construction Tracking file (linked): now refurbishing second package. The plan is to use all the spare cathodes there plus three newly build: all of them using new foils and one spare cathode frame (the only we had), and two refurbished (type-1 and type-2). The refurbished frames came from package #1 by successfully removing the foils. For package #1 we may use some of the cathodes from package #2 that didn't have bad channels (indicated with blue color) and all of the spare foils left after building package #2. | - Dave showed the latest Construction Tracking file (linked): now refurbishing second package. The plan is to use all the spare cathodes there plus three newly build: all of them using new foils and one spare cathode frame (the only we had), and two refurbished (type-1 and type-2). The refurbished frames came from package #1 by successfully removing the foils. For package #1 we may use some of the cathodes from package #2 that didn't have bad channels (indicated with blue color) and all of the spare foils left after building package #2. | ||
Revision as of 17:49, 9 August 2012
August 9, 2012 FDC meeting
Agenda
- Cathode corrosion
- Status tests with water, SEM results
- Testing chambers vacuum chamber tests
- Production Construction Tracking (Dave)
- Cathode production
- Fixing cathodes
- Second package refurbishment
- Engineering (Bill)
- Electronics (Chris, Nick)
- TDR, page 132-145 (Lubomir)
- Other
Minutes
Participants: Bill, Dave, Chris, Nick, Vlad, Eugene, and Lubomir
Cathode corrosion
- Lubomir: a test with cathode foils, Viton/EPDM O-rings and water was done (at Blue Crab dirty area). First, the O-ring samples were pressed against the foils with a lead brick, also using G10 and aluminum plates to equalize the pressure. After a couple of days, water (from the tab) was put on the samples. Corrosion appeared immediately on the next day: very well pronounced on the EPDM sample and resembling the same dark traces that we had on the cathodes of the first and second packages (see first picture above), also some corrosion but with lighter color on the Viton sample. Olga did SEM analyses on the two sample foils at the places of the O-rings: second link above. Generally, the experiment was not done in a clean environment and tab water was used, so you see a lot of dirty stuff like chlorine. At the same time sulfur is visible in almost all the areas of the EPDM sample, while for the Viton sample sulfur is present in much smaller areas visible with high magnification. We started the same experiment inside the clean room using distilled water; expect results next week.
- Three other test experiments are running. One with production cathodes and a wire frame that started more than two weeks ago. Second one with similar samples using the small-scale prototype, running since yesterday when we were able to fix the HV. The third one is the Vlad's experiment using the vacuum chamber (picture linked) with same samples (EPDM, Viton with/without Apiezon) with same gas, but no HV, with some water inside to create moisture and heated with a lamp (only during the day) up to 80degC. We will open it on Monday.
