The following work was done to the T1-MK2 target in the hotcell between the dates of May 24, 2019 - Jan 30, 2020 (See E-Log #251 for further information):

• May 24: Flushed position 2 with water, purged all positions with air.  Left air running through position 0 over the weekend
• May 27: Switched to position 5, left air running to dry out bellows
• May 28: Started pump out with cold-trap;  Reached "fine test" (TP pressure < 10E-2 Torr) after ~10-15 minutes, left for 2 hours, removed ice build-up then restarted leak detector;  
  Down to 1.0E-3 Torr TP pressure and 1.0E-8 Torr*L/s after ~10min
  Leak checked with 5psi helium, ~0.5s spray: Response at lower delta seal right side (when facing ladder) up to 3.8E-6 Torr*L/s and drift responses from nearby locations
• June 27: Position 1 target removed - no issues, required light tapping with hamme
  Position 4 target removed - lots of hammer hits required
  Both target beam spots photographed.  Saw what looks like hole on Position 4 entrance window (see attached photos)
• July 8: Protect monitor inspected visually using Nikon level by Dave Cameron and Shengli Liu - Nothing abnormal observed
  Electrical check w/ multimeter: all OK
  Observed ground to HV plates while moving ladder from Position 5 to 0 - all OK
  Observed ground to HV plates while moving profile monitor IN then OUT - all OK
  Found intermittent short from HV to ground when shaking the target assembly or tapping the protect monitor cassette:  must replace
• July 18: Cleaned Position 1 and 4 Swagelok sealing surfaces on the target ladder using the Dremel tool with burgandy Scotchbrite
  Ready for new targets to be installed
  Plugs installed at Position 4
• July 24: Target #105 installed at Position 1
  Started leak detector pumpdown with cold trap;  Only pumped down to 4.0E-3 Torr;  Big helium response at lower right delta seal (10E-5 Torr*L/s range)
  Concluded that the leak got worse during the target replacement (likely from the hammering required to remove Position 4 target
  Tightened bolts for lower right delta seal then repeated leak check: same results, therefore must replace seals
  Received replacement protect monitor cassette from Probes Group and installed
• July 29: Probes group did blip test on new protect monitor - all OK
  We repeated the test for shorts with shaking and tapping on the target assembly and monitor - no shorts observed
  Concluded that protect monitor issues is now fixed
• Early Jan 2020: Lower cone and plate removed, ladder removed (old style w/o plate at top)
  Removed seal spacers, the one for the lower right delta seal was stuck, had to use a flat edge screwdriver as a wedge with aluminum hammer to dislodge
  Removed delta seals, observed some deposits or corrosion at lower right seal location
  Cleaned spacers using Scotchbrite on Dremel
  Used 3D printed jigs with glued on burgandy Scotchbrite to clean sealing surfaces (no air ratchet or dremel, polished with manipulators until a clean shiny surface was produced)
  Had to remove bolts for the ladder flanges to clean the surfaces, and when reinstalling one of them it cross threaded and couldnt be removed
  Bolted instead at different hole locations (still at opposite sides of flange) but also had to switch bolt locations on upper seals to do this because bolts will interfere if using same threaded hole
  Eventually got everything back together with new delta seals installed (TBP0454B, machine shop order #44138)
  Note: the upper delta seals were not disturbed - new bolts installed and torqued before old ones were removed
• Jan 22: Leak check, pumped with cold trap: down to 0.0E-10 Torr*L/s and 1.0E-3Torr TP pressure after 9.5 minutes
  Using 5 psi helium, 0.5s spray;  No response at any previous locations;  Very small drift response up to 0.5E-10 Torr*L/s
  Concluded that leak is fixed
• Jan 26: Base plate and cone reinstalled - no issues
• Jan 30: David Kyle and Shengli Liu re-tested the profile monitor and protect monitors - No issues
  Measured vertical and horizontal positions for all targets and protect monitor, updated measurements sheet (PDF attached)
  Ladder moved to Position 0
  Target assembly ready to be moved to storage pit
   

 Annual MRO work on the T1 and T2 cooling packages is now complete.  The following tasks were performed:

• Water from both packages drained to the South TNF holding tank (samples taken)
• All Proteus paddle wheels, shafts, and o-rings replaced (5 each at T1 and T2)
• All Cuno filters changed
• Archived data for all sensor readbacks inspected.  Only faulty sensor was B1A:T1CS:FGDEM
• Both packages refilled and restarted; Operating smoothly; Inspected for leaks, none found; Demin flow at ~1.0gpm
• B1A:T1CS:FGDEM readback is fixed with new paddle wheel
• South TNF holding tank water released after approval from RPG
• Old filters added to plastic pail with other T1/T2 filters located directly north of the BL1A blocks boot-box area
• Active water from filter canisters dumped into the RH lab active sink

 The T1-MK2 target was moved from the hot cell to Hole #5 in the storage pit.  The M9 beam blocker was then moved from the beamline to the hot cell for MRO work.  A field of 14.4mSv/hr was measured at 0.5m from the beam blocker during removal.

 The M9 service stand floor plate (TB23351) was installed in the M9 pit yesterday.  Prior to installation all 5 threaded inserts were tested using a 1/2"-13 stud tool on an RH pole.  The west most hole (shown in red below) had damaged threads and the stud could only be threaded in 2 turns.  All other locations (shown in green) had usable threads with 6-8 full turns possible with the stud tool.  The plate was installed using RH floor plate bolts (TB23382) at all four locations with viable threads.  The bolts were torqued to 30 ft*lbs which on a bench test was shown to fully compress the belleville washer.  The standard torque spec for 1/2"-13 stainless bolts (43 ft*lbs) was not used to allow easier disassembly in the future.

 The M9 Q1Q2 "foot" plate (TB23363) has been installed over the floor plate.  A nominal gap between the plates of 1/2" was set before lowering the plate, it was then leveled using the three adjustment bolts resulting in a larger gap.  After leveling, the plate was lifted to remove the spirit levels and lock the position of the leveling bolts.  The plate was then re-lowered and the tiedown bolt assemblies (TB23383) were installed using 50ft*lbf of torque (about the maximum practical amount with standard 20' pole tools)

M9 beam blocker MRO work was completed in the hot cell today.  This included replacement of the main shaft seals and replacement of the air cylinders.  Actuation was tested after replacement and the blocker moved smoothly through the full length of travel with approximately 45psi air pressure.  It is ready for transport back to the beamline.

The M9 beam blocker was returned to the beamline today using the RH shielded transport flask.  The top flange o-ring was replaced before installation.

After installation the "Lift T" assembly was removed, and electrical cable and air supply connected.  Correct functionality of the limit switches was confirmed with the control room.  Actuation of the beam blocker could not be tested at this time because control takes place through the M9 area ASU.

 The 10-pin thermal switch wire, 2-pin steering wire for Q2, and a 1/4" copper tube for remote helium leak check were installed through the service chase with the power cables and connected to the M9 service stand.  Approximately 10m of extra cable (2-pin and 10-pin) was coiled and left in the cooler section of the service chase after the first sharp bend.  The cables and the tubing are currently run as far as the vertical cable tray "waterfall" located near the M11 area.

 Laser tracker scan data from 2017 and 2019 attached as a backup.  Original files from Beamlines Group who also keep copies on \\trwindata\experimental support\alignment\T2-M9_data

The Q1Q2 water header (TB23481) was mounted this morning as per installation drawing TB23400.

Heat shrink tubing was applied to the B1 power cables (two positive, two negative) over the length of cable in the highest field which was showing some signs of radiation damage on the insulation.  The tubing used was McMaster-Carr PN 75665K932 (Clear PTFE, 4:1 shrink ratio, 1.0" ID before shrinking), as recommended by Syd Kreitzman.  Each piece of tubing is 4' long, and two were used per cable.  The first one was shrunk along its full length, then the second piece was only shrunk where it overlaps the first and the remainder was left loose.  This was done to minimize time required in the high dose area.

Hand-stacked concrete bricks were removed from the location where the new piping will run to the water header.  This is scheduled to take place between July 6-8

 The M9 Q1Q2 magnet assembly lift beam has been installed according to drawing TB23401.  The side-to-side as well as beam-axis direction adjustment features were tuned so that the assembly is level when lifted.

Aug 5, 2020 update:  All fasteners on the lift beam assembly have been torqued according to the specification on drawing TB23401

The diagram below shows the wiring for the two connectors on the service stand (the wires running from the stand to the power supplies.  (see TB23400 for details)

 Mike Vogel reported that alignment of the Q1Q2 assembly w.r.t. the T2 and B1 flanges was completed on July 7.  This was performed in the test stand with the flange positions set to the measurements taken in the 2019 shutdown.  Alignment to the theoretical location was achieved within 0.1mm.

The axis of the Q1 and Q2 magnets were aligned to each other previously within similar accuracy.

The following work was completed during the 2020 shutdown period for BL1A (Jan-Aug 2020):

• T1 and T2 EPICS data checked for anomalies.  None found, all sensors behaving as expected
• T1 and T2 cooling package water drained to storage tank, sampled, and released
• All cuno filters changed (3 for T1, 2 for T2)
• All T1 and T2 proteus paddle wheels changed
• T1 and T2 hansen fitting connections inspected: all good, no leaks
• Both packages refilled, restarted, demin flow tuned to 1gpm, and checked for leaks: very small leak from 3/4" line going into heat exchanger on T1 target loop (not new, tightening doesn't help) 

• Profile monitor air hoses inspected: ok
• Air amplifiers inspected: cycle time ok, no leaks
• M9 beam blocker overhaul completed including new air cylinders
• M9 and M20 BB actuation checked
• T1 and T2 profile monitor actuation checked
• T1 and T2 ladder movement checked
• XTPAGE 7L updated to indicate which targets spent
• Target ladder status sheet updated
• ASCO valves for M9BB, M20BB, T1 prof mon, T2 prof mon all serviced (with rebuild kit)

August 25, 2020 update:

- The cap block was replaced over T2
- Actuation of the M9-T2 and M20 beam blockers was tested.  Both moved fine and limits displayed correctly

The T2 Collimator A flow meter signal (B1A:T2:FGCOLA) began fluctuating and occasionally reading 0gpm on Sunday Oct 25 causing BL1A trips and machine down time.

On the maintenance day today (Tues Oct 27), the T2 package was uncovered and the T2 Col. A flow meter was opened.  No unusual deposits were observed as seen recently with other flowmeters for BL1A magnets on the CuALCW system.  Some minor wear was observed on the dowel pin shaft, and the paddle wheel didn't spin quite as freely as when new.  A small amount of reddish/brown film (rust?) was seen on the internal SS faces.  The faces were wiped clean and new dowel pin, paddle wheel and o-ring were installed.

The pin, paddlewheel, and o-ring were also replaced for B1A:T2:FGCOLB (no wear observed on old pin) and B1A:T2CS:FGTGT (some wear observed on pin, more than Col. A).  They were not replaced on B1A:T2CS:FGSEC or B1A:T2CS:FGDEM at this time, as neither of these has a noisy signal, and neither can cause trips in the control system.

After all paddlewheels were re-installed and the system restarted, the flowmeters behaved as expected.  The fluctuations that occurred on Sunday were not happening this morning prior to the change, so we're unsure at this point if this has solved the problem.  StripTool was used before and after the change to observe fluctuations in the readbacks, and no noticeable difference was observed.

During testing of the flow meters we observed that B1A:T2:SVCOLB seemed to not respond one of the times it was commanded to close, and one or two other times it seemed to close after a few seconds delay.

Note: All T1 and T2 paddlewheels, pins, and o-rings were changed earlier this year.  They're scheduled to be replaced every 2 years as per the T1/T2 maintenance plan.

 The following work on the T2-MK1 target was completed sporadically over the last few months:

Sept 22:
- T2-MK1 target moved from storage pit to hot cell (new camera view to check flask doors and latch engagement works great)
- Rubber pad from storage pit standoffs was stuck under flange - removed and cleaned base of flange
- Preliminary leak check: target positions and  delta seals no response, left bellows (facing ladder) had tiny response up to 3.0E-8 with recovery in ~5s, right bellows no response
- Removed plugs at Position #1 and #3

Oct 14:
- Installed 12mm Be target #106 at Position 1 (confirmed with Yuri that it may be useful to have a short Be target on the T2 ladder)
- Installed 5cm target #301 at Position 3
- Leak checked target positions: no response, only mild delayed drift
- Position 4 plugs removed

Nov 10:
- Installed 5cm target #302 at Position 4
- Repeated leak check: no response at all target positions
- Took vertical and horizontal measurements for all new targets
- Position limit switches and potentiometer confirmed working ok

Nov 24:
- Moved to Storage Pit Hole #4
 

A trial run of remote removal of the UCN target was performed using the shielded target cask (TTA0335) developed in 2020.  The work took place between Feb 9 - 17 under work permit C2021-02-09-1.

The procedure in work instruction Document-187117 R1 was followed. Draining and purging of the water system as well as venting of helium from the target crypt was performed by Tony Hessels.  The remainder of the procedure was carried out by Keith Ng, Maico Dalla Valle, and Isaac Earle.  A maximum field of 1.7mSv/hr was measured at 0.5m from the bare target;  This is higher than the approximate 500uSv/hr field that was expected, however dose incurred during the work was minimal (Isaac: 0.05mSv, Maico: 0.03mSv, Keith: 0.03mSv).

The cask aligned well to the target arm and no modifications to the cask or UCN hardware were required to carry out the procedure.  A few updates will be required to the work instruction document based on discoveries made during the procedure; notably: 

• Cask to be installed on the west side of where the water tubing connections for the crypt flange are located;  As a result the cask lid will be installed after the cask base (with target forearm inside) is removed from the rails
• Shims are not required under blocks TTA0550 and TTA0555 in order to clear the top of the cask (the concrete and steel supports for these blocks are higher than in the UCN area shielding model)
• In addition to the six 3/8"-16 bolts for the water manifold, two shoulders screws (one on each side of the manifold) must also be removed to allow the two halves to separate

The work instruction document will be updated to include the changes above, as well as other minor updates and extra figures. 

After testing, the target forearm was reinstalled and all connections re-made.  Leak checking of the water connections and crypt flange as well as testing of the target thermocouple signals is to be arranged by the UCN Group.  The cask has been stored on top of concrete shielding on the B2 level north-east of the UCN experimental area.

Various photos taken during the procedure are attached.

 The RH Lab Active Sump reached the high level sensor at some point overnight before the April 8th work day.  Maico Dalla Valle noticed the alarm in the morning and notified RPG and myself.  I also received a notification by e-mail from Vicky Hannemayer who had been contacted by Ops because of the RCR alarm.

After sampling and testing by RPG the sump contents were released under work permit C2021-04-08-5 as per the procedure in Document-64834.  The approximate volume of the full sump is 7270L.

T2 target water leak was identified earlier this morning.

Isaac Earle, Ron Kuramoto and Keith Ng co-ordinated Meson Hall blocks removal and target flask transport.

Target assembly was removed from B/L approximately 5pm.

Vacuum "suck tube" (capacity ~ 10L) for removing water in B/L was prepared by Isaac Earle.

Approximately 5 L of water was seen in the bottom of the T2 target ladder vacuum tube enclosure, referenced by the ladder assembly locating spigot (see attached photo).

Most of the water was removed by Grant Minor, Ron Kuramoto, and Keith Ng using the suck tube, job finishing around 8pm November 22nd.

About 1/8" water remains in the bottom of the vacuum tube enclosure, which will have to be left to evaporation overnight and vacuum pumps (see attached photo).

Full suck tube was tagged and left on the north-east side of the Meson Hall blocks near TNF.

Spare target replacement, pump down and block replacement to happen tomorrow, Isaac Earle and Grant Minor to co-ordinate w/ support from Plant Group and Vacuum Group.

The T2 target was exercised to position 0 around 6:15pm so that the T2 profile monitor could be used by operations.  The T2 water package was re-enabled when the target was in position 0, however this resulted in some trips of the cooling package.

Operations called around 7:45 to request return of the target to about 2mm above position 4.

The target position was re-set so that the position reading fluctuated roughly between 2.7 and 1.6 mm above position 4 (hovering roughly around 2.0 mm), and so the potentiometer reading was hovering roughly between 0.801 and 0.798.

The cooling package was re-started, and called operations to confirm the system was OK.