Meeting Notes

Hytec Inc

February 1 & 2, 2001

1. The goals of the meeting were reviewed: Exchange information on the tooling and assembly procedures, Pisa is working in parallel for the testing (vibration and thermal) required as well as setting up the fabrication and assembly facilities to build the EM trays.
2. Hytec presented a review of the Tracker requirements. All the slides for all of the Hytec presentation will be placed on the web.
3. The detailed tray mechanical design was reviewed. There is no experience with titanium inserts in Italy for the 1.6mm screws, several samples were fabricated and given to Sandro to show to industry. The closeout insert design was modified to have a “top hat” instead of the conical shape to simplify the assembly and alignment procedures. Sandro will check with the European supplier of the carbon/carbon material and see if they could provide the closeouts in final machined form.
4. Tom will discuss various testing scenarios with Martin Nordby for the prototype “tower”. Will there be a prototype grid that could be used? Will there be a prototype, or mass model, of the calorimeter for a combined test?
5. A detailed discussion of the tooling fixtures and assembly procedures, based on the Hytec presentation, helped the level of understanding between SLAC/Hytec and Pisa. Hytec will look into adding two extra tooling holes in the non-MCM closeouts for ladder placement per a request by Sandro. A more complete analysis of the tolerance stack up needs to be completed before the final procedures can be issued. Hytec will put the final draft of the closeouts and the assembly tooling on their website by EOB Friday Feb 9, 2001. Sandro will use these drawings in discussions with Italian industry the week of Feb 12-16.
6. Sandro requested further information and confirmation that 200 micrometers of Kapton material is required in the cables and bias circuit between ground and the 150-volt bias voltage.
7. Sandro presented the tooling design for the ladders. The use of some of the tooling used for tray assembly being used also for ladder assembly was discussed.
8. Enrico presented the results of their finite element analysis of the superGLAST trays. It was agreed that a test of the entire system, thermal cycling, will be performed for all configurations. A reason for the bowing of the tray that showed up in the FEA analysis was discussed and Enrico will review his analysis. The “bowing” is possibly a figment of the fidelity of the grid used for the analysis.
9. A general discussion of the assembly of the tower highlighted some of the concerns with tolerances and the final assembly sequence. Further discussions will take place after the tolerance trade study that Hytec is working on.