Difference between revisions of "Minutes-8-30-2012"

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# [http://www.jlab.org/Hall-D/detector/fdc/general/tdr.pdf TDR, pages 132-145] (Lubomir)
 
# [http://www.jlab.org/Hall-D/detector/fdc/general/tdr.pdf TDR, pages 132-145] (Lubomir)
 
# Other
 
# Other
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= Minutes =
 
= Minutes =
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- Wire frames: Chris will put the resistors on the first PCB set next week. Then we will start laminating the wire plane #29, we have a frame for it. The other three G10 wire frames will come from the machine shop in ~2 weeks. Fernando and Bill confirmed that the new PCBs can be used.  
 
- Wire frames: Chris will put the resistors on the first PCB set next week. Then we will start laminating the wire plane #29, we have a frame for it. The other three G10 wire frames will come from the machine shop in ~2 weeks. Fernando and Bill confirmed that the new PCBs can be used.  
  
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- Quotations came from Allflex  
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- Roger got quotations from Allflex and Flexible Circuits, the two Minnesota companies that made the cathode foils and the rigid-flex assemblies. According to Allflex they have material for 18-19 foils and we asked for 20. We will need the foils for some of the cathodes on package #2. Based on Dave's estimations for the refurbishment of the first package and then completion of the fourth one, we will need the foils sometime in November-December. In any case it's better to submit the PR now and contact Eugene to use funds (~$10K) from FY12.   
  
 
== Cathode corrosion ==
 
== Cathode corrosion ==
  
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- New SEM results from Olga (follow the above link) for the samples from the Vlad's test with the vacuum chamber; the chamber had water inside and the temperature at end of the day (lamps were off overnight) was close to 100degC.  The test was done for about 4 days:
 
  
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*Copper foil with EPDM inside: significant corrosion, a lot of sulfur present.
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== Conductive tape studies ==
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*With the EPDM of the gasket, part of the foil strips were inside the gas chamber and part exposed to the air: no sulfur seen at the air side and a lot of it at the gas side. However, inside the gas volume there was moisture and the temperature was much higher than outside. We had seen corrosion before also in the samples placed in air with some water put on the foils and no heating. We will do more tests.
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*Copper foil with Viton: some traces visible, almost no sulfur there but some chlorine. Tim suggested cleaning the O-rings before installation.
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== Engineering ==
  
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*With Viton and Apiezon: no visible corrosion, only copper and carbon lines are visible, but the grease was not cleaned. Olga will repeat the measurements after cleaning it. 
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- The first testing chamber with production wire frame and cathodes was opened yesterday, exactly 4 weeks operating with HV and gas. Some traces from the EPDM O-ring are visible but it doesn't look like the corrosion on the first and second packages. We conclude that the humidity is an important factor. No traces on the cathode against the Viton+Apiezon O-ring are visible. The test with the small-scale prototype is running two weeks, haven't opened it yet.
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- Tim for the humidity conditions in the Hall: nominally it will be less than 45%, but he can't exclude some periods when it might be higher. There will be dry air blowing through the magnet. We should avoid opening the Hall doors for a long time during the installation.
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== Engineering ==
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- We will have two strong-backs to be used to grab the cathodes from both sides and keep them flat. We discussed how to support the cathode periphery when using the strong-backs. Casey made a table with rods that will be used to store the cathodes in a flat position.
 
- We will have two strong-backs to be used to grab the cathodes from both sides and keep them flat. We discussed how to support the cathode periphery when using the strong-backs. Casey made a table with rods that will be used to store the cathodes in a flat position.

Revision as of 18:26, 30 August 2012

August 30, 2012 FDC meeting

Agenda

  1. Production Construction Tracking (Dave)
  2. Cathode corrosion
    • Recent test results: [1]
  3. Conductive tape studies: [2], [3], [4],[5], [6] (Vlad)
  4. Engineering (Bill)
    • Cathode strong-backs
  5. Electronics (Chris, Nick)
    • PCBs
  6. Third package tests FDC E-log (Beni)
  7. TDR, pages 132-145 (Lubomir)
  8. Other

Minutes

Participants: Fernando, Bill, Dave, Elton, Simon, Chris, Vlad, Beni, and Lubomir

Production

- Dave for: working on all the cathodes for package #1. Using the new tool to hold the cathodes flat, two cathodes moved to tables and the cards are being glued there. Will have cathodes for the first, second, and third cells by next Tuesday, next Thursday, and next next Tuesday respectively. This is assuming one cathode per day, which is limited by the tools that we use now.

- Wire frames: Chris will put the resistors on the first PCB set next week. Then we will start laminating the wire plane #29, we have a frame for it. The other three G10 wire frames will come from the machine shop in ~2 weeks. Fernando and Bill confirmed that the new PCBs can be used.

- Roger got quotations from Allflex and Flexible Circuits, the two Minnesota companies that made the cathode foils and the rigid-flex assemblies. According to Allflex they have material for 18-19 foils and we asked for 20. We will need the foils for some of the cathodes on package #2. Based on Dave's estimations for the refurbishment of the first package and then completion of the fourth one, we will need the foils sometime in November-December. In any case it's better to submit the PR now and contact Eugene to use funds (~$10K) from FY12.

Cathode corrosion

Conductive tape studies

Engineering

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