Uncovered T2 monolith and transferred M20BB to hot cell using flask.

Field at 0.5m from beam blocker while being lifted with flask: 21,700μSv/hr (using pole monitor) 

Field above hole after removing M20BB: 9000μSv/hr

 Replaced M20 beam blocker vacuum seal o-rings.  Old o-rings were noticeably harder, but not brittle or cracked.  Applied "Haskel Dry Air Seal" lubricant to air cylinder shafts and "Apiezon M Grease" to vacuum seal o-rings and main shaft.  Took approximately 1 full days work.  Total dose: 0.08mSv.

 While wrapping up vacuum seal bearing replacement on the M20 beam blocker I found a piece of hard black material approximately 3x1x1cm on top of the hot cell turntable.   Checked for contamination and found 480,000cpm on the Ludlum 44-2 probe, and off scale on the pancake monitor.  This piece fell from the transport flask when it was opened above the hot cell after picking up the M20 beam blocker.  Upon further inspection, more pieces were found inside the hot cell on the table.  RPG was notified and currently has the sample for further testing.

 The broken M20 beam blocker plastic shaft bearing was removed.  Measurements of the bearing as well as the shielding disc (for which drawings can't be found) were taken inside the hot cell and a brass replacement bearing has been designed based on these measurements.

Photos of the removed bearing, measured dimensions of bearing and shielding disc, and a PDF drawing of the new design are attached.

The replacement shaft bearing was machined by Maico Dalla Valle and installed in the beam blocker.  Smooth operation of the beam blocker air cylinders was confirmed, and the beam blocker is scheduled to be re-installed in the T2 monolith on Monday morning (Jan 23).

M20 beam blocker was transferred from the hot cell to the beam line.
M9 beam blocker was transferred from the beam line to the hot cell.

Field at 50cm from M9 beam blocker during removal: 5000μSv/hr
Field above M9BB hole on monolith after removal: 3500μSv/hr

Unlike M20BB, M9BB has an unmodified lower shielding plate, and no plastic bushing.

M9 beam blocker returned to beam line.

T2 target disconnected, picked up using flask, and returned to beam line as training exercise.
Field @ 50cm from T2 target during removal:  ~90,000μSv/hr

Resin can flask with new resin moved from hot cell lab to T1 cooling package area.

 The faulty air pressure supply check valve for M9BB, M20BB, and T2 Profile Monitor was replaced.

The rotor, shaft, and o-ring were replaced on the Q4 flow transducer to address erroneous readout that began last week.
The attached plot shows the flow readout before failure, during the failed state, and after repair.

 The air hoses for the profile monitor supply line were inspected and no cracking was found (was found on T2).  The quick connect fittings for the bottom air assembly were sticky/corroded and not actuating properly.  Replaced fittings with new parts.

The T1-MK2 target was transferred from the beam line to the hot cell.  Water was seen in the bottom of the target pipe confirming that the leak is from the target.  The lower cone of the target assembly was submerged in the water and came up dripping wet.  The profile monitor, protect monitor, and two of the target cassettes were also wet.  As it is not possible for those to be submerged, water was likely spraying from either the bellows flanges, or somewhere on the target ladder.  It is estimated that 15L - 20L of water leaked from the target in total.

Inspection, leak checking, and repair on the target will begin next week.  We will suck up as much of the water in the beam line as possible from the top of the monolith using a suction device designed for this purpose.  The remainder will have to be pumped out by vacuum group.

All water was removed from the base of the target hole in the T1 monolith using a suction tube device and wypalls.  Video inspection was performed and revealed standing water in the unused 4" beam line pipe facing south as well as on the bellows on the M13 beam line.  (Photos attached)

Vacuum group is currently pumping down on the T1 volume to remove the remainder of the water.

 The T1-MK1 target was transferred from the storage pit to the beam line.  Services were hooked up and the cooling package was started (operating normally).

Target ladder documentation and elevation values for the new target were delivered to operations.

 Graham Waters has activated the appropriate target ladder position look-up tables for the T1-MK1 target which was installed in the beam line yesterday.

Vacuum interlock defeat jumpers were removed for T1 and T2.  The interlock was tested by venting the T1 and T2 volumes.  Both packages registered a vacuum trip, however only the T1 package shut off.  A fault report has been filed to investigate this.

Controls group identified that issues with remote actuation of the profile monitor at T2 was due to a short-circuit on limit switch wires on the target assembly.  The relevant wiring assembly was removed from the target and controls group is preparing a replacement.

This morning it was noticed that the warning level indicator for T2 expansion tank displays as tripped on XTPAGE.  The level was checked in the tank and has not moved (is well above the warning level float).  I will investigate further and contact controls group if a solution is not forthcoming.

Controls Group replaced the wiring and wire harness for the profile monitor limit switches on T2.  The monitor was actuated remotely and functioned properly.

The T1 profile monitor was also tested and actuated properly.  The T1 monolith is now ready to be covered so that blocks may be removed from the M20 area.

 Diagnostics group completed their "blip" signal response tests on the T1 and T2 profile and protect monitors.  A small amount of leakage was observed on the T2 profile monitor, but was not thought to be a significant concern.  All other results were normal.

 The problem with the T2 vacuum interlock was fixed by restarting the "Crate TG1" control panel microprocessor.  The T1 and T2 vacuum interlocks were retested several times and are functioning properly.  Fault report #5907 was returned.

Graham Waters investigated the faulty signal from T2 expansion tank warning level sensor.  The problem was found to be a loose cable at the panels.  The connection was restored and the level sensors are now displaying correctly.

 In preparation for extended periods of the T2 volume being vented during the M20 repair, the T2 water package was shut-off, the water lines were disconnected from the target, and the cooling water was removed from the target using compressed air.

 While working on the leak repair of the T1-MK2 target in the hot cell on Friday April 20th, a cable snapped on the slave end of the right side manipulator.  It is suspected to be the 'Y' shaped cable assembly that actuates the grippers when the lever is pulled on the master end.

The target repair job cannot continue until the manipulator is repaired.  The repair job may take up to a full week, and will require space in the Remote Handling lab as well as use of the house crane, therefore the job will have to be scheduled strategically to avoid interfering with the M20 Q1/Q2 magnet repair which is on critical path and also requires use of the crane.

 The west side manipulator was removed from the hot cell using the new manipulator removal frame.  The operation went smoothly and required about one hour with two operators after everything had been prepared.  No contamination was found on the manipulator thru-tube or slave arm.  Only 50cpm were measured on the wrist assembly of the slave end.