FPIX extraction during LS1 Rachel Yohay University of California, Davis Pixel general meeting May 13, 2013
Outline • Basic sequence of steps • Overall impression • Individual items of interest • Uncabling • Beam pipe support position • Tools • Initial position of synchronous pull drive • Asynchronous pull into CTUs (cylinder transport units) • Placing half cylinder into cold box • Conclusions R. Yohay Pixel general meeting 13 May 2013 2
Basic sequence of steps 2.Set up equipment 1.Un-cable FPIX • Crane both CTU/VIF (vibration isolation frame) pairs to pixel platform • Attach base frame (for mounting extension rails and synchronous pull rod), extension rails (to extend up to the FPIX rails inside the tracker), and synchronous pull rod to pixel table • Align everything to the FPIX rails inside the tracker 4.Mount CTUs to base frame and pull 3.Perform synchronous pull for ~1 m half cylinders into CTUs (feet at higher |z| value will exit the tracker onto the extension rails) 6.Unpack CTUs and lift half cylinders into cold boxes 5.Place CTUs in VIFs, pack up, and crane both CTU/VIF pairs to clean room R. Yohay Pixel general meeting 13 May 2013 3
Overall impression • No major hiccups • New people were trained and were able to help out • Proceeded much more quickly the second day than the first • By the second day, much of the procedure was committed to memory • Better parallelization of tasks (at the cost of attention to detail?) • New people more familiar with the procedure • Existing documentation proved useful but could benefit from some revision • All personnel actively kept an eye on others’ distance to activated areas and reminded them to minimize their exposure—no single person integrated more than 8 μ S in a single day R. Yohay Pixel general meeting 13 May 2013 4
Uncabling • 1h40m with 3 people • 1 person as the primary uncabler per half cylinder • 1 person helping the primaries with tools, garbage bags, connector covers, etc. • Important to have a fresh pair of eyes inspect the uncabling before proceeding (during the +z extraction 1 cable was accidentally left plugged in until it was spotted during the synchronous pull) • Ideas for improvement • 2-3 each of long Allen wrenches needed to unscrew the optical connectors (had 1 of these + 1 shorter Allen wrench) • 2-3 each of straight and angled-nose pliers for securing the HV/LV/DCS connector standoffs (had 1 straight and 1 angled) • 2-3 each of flathead screwdrivers needed to unscrew the HV/LV/DCS connectors (had 1) R. Yohay Pixel general meeting 13 May 2013 5
Beam pipe support position Correct ✔ Incorrect ✘ y x z R. Yohay Pixel general meeting 13 May 2013 6
Tools • Tools were pulled from the SX5 clean room and the TIF and organized in dedicated toolboxes • Sneeze guards forgotten upstairs during the -z extraction ⇒ 20 minute delay to retrieve them • Plan to draw up a tools/materials checklist for next time R. Yohay Pixel general meeting 13 May 2013 7
Initial position of synchronous pull drive • For controlled synchronous push/ pull, hand crank is used • Setting the initial position of the drive (no detector attached) can be sped up by using a power drill with a Screw (turning Synchronous hex attachment screw causes drive pull drive to move in z) R. Yohay Pixel general meeting 13 May 2013 8
Asynchronous pull into CTUs • On the second day, 2 teams simultaneously pulled the 2 half cylinders into CTUs without any trouble • Time savings, but some concern that attention to detail is sacrificed for speed R. Yohay Pixel general meeting 13 May 2013 9
Placing half cylinder into cold box • Minor damage to carbon fiber on 1 half cylinder Screw • Half cylinder brushed against large fixing screw when trying to center half cylinder in cold box Half cylinder • Carbon fiber pieces will be vacuumed away by RP group View from top • Change of procedure: remove fixing screw, place half cylinder in box, then reseat screw and fix half cylinder in place Cold box Half cylinder Screw R. Yohay Pixel general meeting 13 May 2013 10
Conclusions • Successful FPIX extraction during LS1 • Lessons learned will be incorporated into revised documentation • New personnel trained and ready for the insertion next year • Some room for improvement in the procedures regarding ALARA, but personnel took radiation safety seriously R. Yohay Pixel general meeting 13 May 2013 11
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