When the damage to the T2 Protect Monitor was found to be caused by flying debris from a vacuum spike (see e-log #179), it was decided that the T1 Protect Monitor should also be replaced.
Oct 8:
- The T1-MK2 target was transported from the beam line to the hot cell after the T2 target was returned to the beamline (see e-log #180). The T1 target was 38.9mSv/hr at 0.5m
- The T1 target was inspected in the hot cell: profile monitor looked ok, protect monitor damaged with holes and dents on upstream side (see attached photos), position 4 target looked ok with beam spots roughly centered (see photos)
- The old protect monitor was removed in the hot cell and a new monitor supplied by Probes Group was installed (previously undocumented brass spacers were seen over the monitor cassette alignment pins on the target)
- The T1-MK2 profile and protect monitors were checked by Probes Group at the hot cell --> both ok
- Measured elevation of the new T1-MK2 protect monitor: 1831.1mm on entrance side (previously 1831.0 --> ok)
- Position 4 target entrance side elevation checked: 1832.9mm (previously 1831.9mm --> 1mm discrepancy)
- Position 4 exit side elevation measured: 1832.4mm (previously 1832.1mm --> ok)
- Protect monitor exit side elevation measured: 1833.7mm (previously 1833.3 --> ok)
- T1-MK2 target returned to beamline at approximately 5pm, no problems
- Vacuum pumped down quickly and it was decided that a leak check would not be necessary
Oct 9:
- All target services attached
- T1 target moved to Position 0 using remote control box
- T1 package started, no change to T1 vacuum
- T1 profile monitor and protect monitor electronics checked by Probes Group from mezzannine --> both ok
- T1 motor drive cable conected to controller in 1A racks. The T1 ladder can be moved from the 1A racks mimic panel (T2 still requires portable control box)
- Actuation of the T1 profile monitor was tested --> actuated properly, no change in vacuum
- T1 cooling package expansion tank level checked: no change
- The T1 area is ready to be covered |