UCx #42 moved from North Hot Cell to Storage Vault in Pail #282. Placed in slot 6B. Tray 6 is now full. Pail measured at 34.9 mSv/h at ~1 m upon removal from the hot cell. See attached updated spreadsheet. 

Upon attempting to lower Pail 211 into their tile hole, CNL encountered issues with the pail getting stuck. They shipped the pail back to TRIUMF and requested we perform an investigation. The investigation report is attached.

The pail contents must be re-packaged into a new pail.

Note: the F-308 is currently sitting in the Meson Hall warm cell at approximately 250 uSv/h at 0.5 m.

Dose for primary worker (Chad Fisher) who inspected the cable, unbolted the flask lid, and handled the pail briefly: approx. 104 uSv

Dose for secondary worker (Danka Krsmanovic) who swiped the pail and flask to check for contamination: approx. 70 uSv

More photos available upon request from Adam Newsome.

The following four pails were moved from the main storage vault to the mini storage vault, to stage for shipping in Jan. 2024:

1. Pail 260 (SiC#41), Tray 5B
2. Pail 271 (SiC#42), Tray 2B
3. Pail 246 (Nb#10), Tray 6C
4. Pail 265 (UCx#36), Tray 2A

There is current one open slot in the mini storage vault which is planned for the Ta#58 target (formerly in Pail 211, to be repacked in Dec. 2023).

Target Index spreadsheet updated.

See attached printout with mini storage status.

During operation today, it was observed that the main vault door had issues opening.. typically when the door was around 80-90% opened, it would stop motion. Note that this issue has allegedly been present since early 2023. It appeared that the motor was still spinning but the clutch was slipping. This issue was consistent and observed multiple times when trays 2, 5, and 6 were engaged (note these are all on the same side of the vault). It was overcome by backing the door up slightly then trying again. The door close function worked with no issue.

It is suspected that there is a problem with the clutch or potentially a piece of debris on the track. [no longer true after 2023-11-17 inspection]

Edit [2023-11-17]: Maico Dalla Valle and Adam Newsome inspected the vault on 2023-11-17. It was very clear that the door, when opening, is rubbing up against the rails. Specifically, the side rollers located on each side of the vault (red housing). There are clear wear marks on each side. The skew is obvious because on one side, the wear marks begin immediately and stop halfway through travel, whereas the other side shows the reverse wear pattern. It is therefore suspected that the skew has become so significant that the friction is too high towards the end of travel which causes the clutch to slip. The travel rails were cleaned (significant grime buildup) and the offending side was filed down slightly (a sharp burr was present from the wear). It is not advised to adjust the clutch. Next steps: open and close the vault with no trays engaged to see if the issue persists (perhaps weight distribution was the issue), and then try different combinations of weight distribution to try to replicate the issue. After this, measure separation distance between guide rails at different points and try to identify the source of the skew issue and rectify it.
 

Edit [2023-11-20]: Maico and Adam performed further investigation by opening and closing the vault door under 3 different configurations: no trays engaged, 2 trays engaged on West side, 2 trays engaged on East side. The previously observed stopping issue was not observed this time under multiple cycles with each configuration. It is noted that the door appears to slow down slightly and experience a bit of a "chugging along" motion towards the end of travel when opening. Based on these observations, it is concluded that the cleaning and filing helped enough to allow the door to fully travel open/close without getting stuck. The root cause of the issue still remains to be fixed, but for now there is no major concern. Before end of 2023, measurements and planning will be performed to develop a proper repair for the root cause. It is expected that either late 2023 or early 2024, the repair will be attempted.

Edit [2023-11-22]: during a routine spent target exchange, the issue was not observed when opening tray number 2. 

Edit [2023-11-24]: a dial indicator was set up on the vault on the right side (looking down from above), mounted on the traveling part with the tip touching the black structural member where the wear is observed. The purpose is to determine how much out of alignment the door is with respect to the structural assembly. The following was observed: approximately halfway through the travel, the indicator read approximately 185 thou of travel. This corresponds to when the wear marks start to occur and where the small red enclosure around the roller wheel interferes with the structural member (causing the wear strip). At this point, as expected, the indicator no longer changes because the roller wheel has bumped up against the structural member. This implies the gap between the structural member and the roller wheel, when the door is closed, is approx. 185 thou on the right side (and 0 on the left side). These values reverse around the midpoint of travel. It is suspected that because of this, and because there is a small observable gap between the door and the vault when it is fully close, the right and left side of the door are not parallel with respect to each other. In other words, adjusting the angle so that the starting gap is roughly 92.5 thou on each side should resolve the issue. Measurements to confirm parallel-ness between each side will be performed, and then an adjustment will be made to create even gaps between each side at the starting point. After this, a dial indicator will be set up again to confirm that, when opening the door, the gap is maintained throughout the duration of travel. Small deviations are acceptable, but in general what should be observed is a roughly constant gap, and no interference (i.e. if the gap begins at 92.5 thou, it should not drop to 0 or not exceed 185 thou, but should hover somewhere on the order of 20 to 140 thou, for example).

 

Edit [2023-11-24, 2]: a dial indicator was set up on the left side of the vault in a similar manner as described above. In this case, the indicator's reading remained roughly constant during the start of travel (starting with the door closed and opening it up), with only up to around 10-20 thou variation at first slowly, followed by a slow increase to up to approximately 135 thou. This is similar to the 185 thou observed on the other side. One suggested means of resolving the issue is: raise the entire door slightly with overhead crane, translate it sideways approximately half of door's lateral travel distance (i.e. around 90 thou) and then lowering it back down. This should, in theory, be acceptable. It may not resolve the issue of whether the door is rotated, but should give enough clearance on both sides throughout the entire range of motion to be deemed an acceptable fix. Other opinions will be gathered on the subject to determine if this could work. 

The spent Ta#65 target was removed from the south hot cell and placed in the spent target vault. It was placed in pail #284 and placed in spot 2B. It was 41 mSv/hr at 1 m upon removal. Target index spreadsheet updated.

It is reported that the crane's hook rotation is not working currently. It was working yesterday (Nov 22). Investigation to follow, and this e-log will be updated.

Edit [2023-11-23]: the issue was a result of a tripped circuit breaker. Perhaps the motor became overloaded. It is advised to monitor the rotation mechanism over the new few operations, and rotate the hook CW and CCW prior to performing any critical operation to confirm it is working.

TM3 was moved from the Silo to South Hot Cell.

TM3 has been moved from the target conditioning station to the south hot cell.

TM3 was moved from the SHC to the TCS (no target installed).

Pail 211 which contained Ta#58 spent target was repackaged into Pail 286 in the South Hot Cell.

The dose rate at approx. 1 m was 4.16 mSv/h.

Pail 286 was transferred to the mini-storage vault and placed in the outermost location. The mini-storage vault is full at this time, in preparation for the next shipment.

TM2 was moved from ITW to the South Hot Cell with Ta#66 target.

TM2 was moved with no target attached from the South Hot Cell to a silo.

Today (2024-02-09), five flasks were loaded in preparation for shipment with the following targets: SiC#41, SiC#42, Nb#9, UC#36, Ta#58.

Note: prior to shipping, the pails within these flasks will need to have a crimped lifting loop added to them.

The mini-storage vault is now EMPTY.

The target index spreadsheet has been updated.

Spent target UCx#43 (pail 289) was moved from the South Hot Cell to the Storage Vault, placed in location 2A. Dose rate at 1m was approximately 22.6 mSv/hr.

Target index spreadsheet updated, attached.

In preparation for F-308 loading, three pails were moved from the main storage vault to the mini storage vault. The following pails were moved:

• Pail 270 (C#3)
• Pail 276 (UC#39)
• Pail 231 (UC#41)

Target Index spreadsheet updated, attached.

Today (2024-02-16), three flasks were loaded in preparation for shipment with the following targets: UCx#39, UCx#41 and C#3.

Note: prior to shipping, the pails within these flasks will need to have a crimped lifting loop added to them.

The mini-storage vault is now EMPTY.

The target index spreadsheet has been updated.

TM3 was moved from SHC to NE silo. Cable tray was recently installed.

The annual inspection of the main storage vault will be skipped this year since extensive inspection and testing was performed during the re-alignment job in May (see this e-log for details: e-log 2584). This included successful testing of the emergency close mechanism.

The mini storage vault was informally inspected by Adam Newsome on 2024-06-18. The following was checked:

• Cabling and cable management
• Connectors (note: the strain relief for the remote control input cable was loose - it was tightened)
• Controls box - external connectors and wiring
• Limit switches - wiring, mounting
• Motor visual check
• Drive wheels visual check
• Drive track visual check (note: the track had small pieces of metal shavings on it which were wiped off)
• Bearings visual check
• Miscellaneous fasteners visual check

Photos can be found in G:\remote handling\Facilities and Projects\ISAC\Mini Storage Vault\Inspections

The inspection was generally successful. No areas of concern. Regular inspection will resume next year.

The pail handling tool which is used to move 5 gallon pails around the target hall was inspected by A. Newsome. The main tool was checked, but not the spare as it is currently in a disassembled and unusable state. The tool appears to be in good, working condition. The following items were checked.

• Inspect structural integrity of long tube - check for bending, warpage, dents, cracks, rust/corrosion
• Inspect structural integrity of hook assembly - check for bending, warpage, dents, cracks, rust/corrosion
• Inspect fasteners - check all fasteners installed as per drawings, fasteners are tight (note: one fastener on crane interface subassembly was loose - all fasteners in these subassembly were tightened as a precautionary measure)
• Inspect crane interface assembly - check for damage and wear where the tool connects to the crane
• Check alignment - verify the tool connects to the crane and hangs vertically with no major misalignment (this step was not done - alignment is regularly checked during operations, and there was no concern as the tube was straight)

 Note: these tools are being inspected monthly by D. Wang and F. Song.

Photos can be found in G:\remote handling\Facilities and Projects\ISAC\Pail Handling Tool\Inspections\June 2024

IMPORTANT: the maximum load capacity and lifter tag for the tool are not present. There is a plan in place to affix these two labels in the very near future.

Today (2024-07-05), five flasks were loaded in preparation for shipment with the following targets: SiC#43 (Pail 272), SiC#44 (Pail 275), Ta#63 (Pail 266), UC#40 (Pail 278), UC#38 (Pail 274).

The crimped lifting loop has been applied to each pail. The locks have not yet been applied to the flasks at the time of writing this log, but will be done next week.

The mini-storage vault is now EMPTY. Because some of the pails had contamination (200 - 1500 CPM), it is highly recommended that the mini-storage vault be cleaned or at least swiped for contamination.

The target index spreadsheet has been updated (attached).