March 17, 2017 - 200kV gun upgrade meeting
Last week's action items
1. Carlos/Gabriel/Bubba - Move gun to Test Lab. Validate Matt's assertion of plug-and-play of pure alumina vs. conductive insulator, determine stack-up of flange+insulator+electrode. Close layout/geometry loop between chamber + ME drawings + Poisson. Assess stock materials for shed/electrode e.g. Nb/Nb or SS/SS. Main goal is electrode design, but give some thought to testing HV chamber before dismantling.
2. Phil/Joe - See if can locate two large diameter BPM cans, recall existing length of shorter tunnel NEG w/ bellows each end, sketch proposed tube w/ BPM, magnets, does it all fit?, check with Pete about two channels of electronics
- Pete says super easy
- Installed already: VME electronics, wiring, interconnects, downstairs cables
- Already purchased, ready to install: (2) Transport RF modules, Lmr cable sets for 2 bpm cans
- To do : Install, RG58 cables, update CED, update IOCINSE4, Menu and BPM screens
3. Marcy - Plan A for vacuum can/diagnostics at gun3 valve, what is useful and makes sense.
4. Joe/Scott - Identify hooks into gun switch software (controls, interlocks), propose modification to allow for gun3 removal
- Met w/ Scott Higgins
- Eliminate Gun3 options, w/o breaking dependencies
- Scott will start building a new simplified page, summarize dependencies
- Timeframe : May-June for test, ready for July
5. John/Matt/Joe - Move Spellman to Test Lab, restore comm for controls to power itself, then test w/ Ross probe, get TOSP ready for HV to Spellman, vacuum chamber, start discussion w/ software for EPICS application.
- Good progress this week...
- John moved two Spellman supplies to UITF (one for EPICS app, one for Gun2 HV tests)
- Pam assigned Mike Johnson as the lead, Scott Higgins will involved and start training Mike on present Glassman HVPS, interfaces
6. Carlos/John/software - Deploy a radmon at UITF; use FEL control box?, purchase GM tubes, port software app, add to archiver
New action items
- Electrode/insulator design/fabrication
- Danny/Gabriel/Carlos will iterate on final design : minimize gap over triple point, optimize ceramic/metal gap curvature
- Build electrode/shed from one piece of material 8" cube, not enough Nb, go w/ SS
- Matt will check on 316LN vacuum melt, but let's still check what shop used for 350kV ball electrodes, maybe save time and money
- Plan is to vacuum fire 900C, barrel polish before attaching to ceramic
- Reuse springs/rollers/cage, but new rear support ring optimized for electrode
- Collect as-found on white insulator assembly and black insulator
- Finalize design by next week, get to shop
- Vacuum chamber/considerations
- Plan A - Use as-is, but identify/repair short of NEG isolation, retain leak valve but add right angle for isolation
- Do we forego NEG isolation and remove unnecessary ceramic plates (fallen to bottom of chamber)
- Plan B - Rotate NEG's => remove NEG's, weld support rods, NEG coat chamber, return X number of NEGs, new ground screen, retain leak valve w/ right angle valve
- Gun2 NEG Tube
- As-found of existing Gun2 NEG
- Find/leak check cans
- Give Danny sketch of sequence for new tube w/ BPM's + magnets, eliminate/shorten downstream bellows
- All assembled FH solenoids spoken for; take from Gun3, maybe spare parts, or fabricate new coils
- Retain downstream chamber w/ extractor, RGA, GP-100 w/o NF3/Cs
- Remove gun table and HV section
- As-found of existing Gun3
- Spellman HVPS update...
- Radmon update...