August 9, 2010 CDC Meeting

Meeting Time and Place

Monday Aug 9, 2010 at 2:30pm At Jefferson Lab, the meeting will be held in room CC F326

Connections

To connect from the outside, please use ESNET
1.) ESNET: 8542553
2.) Phone:
+1-800-377-8846 : US
+1-888-276-7715 : Canada
+1-302-709-8424 : International
then enter participant code: 77438230# (remember the "#")

Agenda

• Discuss assembly drawings for CDC [Link to Slava's web]
• Discuss straw tube and plastic feedthru futures

Crimp pins from Acumetrics

Discussions

• • In attendance Gary Wilkin, Curtis Meyer, Naomi Jarvis, Slava Razmyslovich, Beni Zihlman, Tim Whitlatch
• Gary is currently testing samples for gluing the inner shell to the inner ring using the spare inner shell supplied by JLAB
• Discussed outer shell - consists of 2 1.5mm thk aluminum half shells rolled to shape. These will be glued to the G10 outer rings. The outer rings consist of G10 strips formed and glued in place. The outer shell gaps will be covered with copper tape (non-conductive adhesive) and then covered with another tape to ensure sealing (TBD)
• Does the outer shel need to be grounded to the upstream aluminum plate?
• Revisited gas flow. Gas enters through tubes (.25 inch) to the downstream plenum, then into straws, then into upstream plenum, then to inner volume surrounding straws and exits from there. We discussed the current gas tube design and will need to revisit as CMU had some concerns. A question was considered as to use plastic or aluminum tubes and how they should be attached (glue, compression fittings etc...
• Discussed upstream standoffs (through alum disk from spacer rods to polycarbonate plate). CMU suggested to remove gas seals from the both ends and use .05 thk teflon washers to seal (and possible prevent rotation of disc during torquing). Also remove studs on ends so polycarbonate plate can be installed easier. Also, it was decided to get the standoffs made now so CMU does not have to change out for shoulder bolts at a later time. Jlab will have standoffs made. 3 of the inner standoffs will have studs.
• Plastic feedthrus should be ready for checking in september
• Crimp pins from Acumetrics were returned to get the inner holes re cleaned (ultrasonically)to clear the inner holes. CMU will re check when they return so we can have a future alternate vendor.
• Straw tubes scheduled for shipment by August 29th

New Action Items

• Produce drawings and fabricate 12 standoffs for upstream gas plenum (JLAB)
• Review drawings for standoff for fabrication (CMU)
• Discuss grounding needs of outer shell to upstream aluminum disc with Fernando (JLAB)
• Review current gas tube assembly and suggest an alternative (CMU)
• Look at sealing tape alternative for covering outer shell gap (CMU)