Friday, April 30, 2021, 14:06

Anders and Luca

Resistance measurements on each electrical feedthroughs (A,B,C,D,E,I,P,Q,R,U,60kV,ground) taken with no target or no short attached to the module. Results as expected:

P-Q = 6.439 mOhm

R-U = 6.019 mOhm

All other combinations = Open Loop

prep'ed area for work:

- removed shield plug from window clamp area

- inspected clamp from tunnel side and from top of target station: video recorder was not working, will try again tomorrow.

- corrosion seen on beam pipe cradles, see photos. corrosion also seen on beampipe, clamp and vacuum tank. will try to vaccuum loose rust tomorrow.

note: gamma spec of rust, white powder from RPG located in \\trwindata\groups\remote handling\Documents\2014\2A3 Window folder (added pdfs as attachments 2014 mar 4)

Video inspected 2a3 window joint this morning.

Screenshots from video showing debris forming around aluminum cradle and brown/red dust on top of beam pipe.

Inspection video can be seen in its entirety at \\trwindata\groups\remote handling\Videos\2014\2014_2A3window

Cleaned top of the ITE vacuum flange and top of window clamp. Attempted to clean the bellows/beam pipe through the wall, mostly dust and small particles. When cleaning bottom of the wall penetration we picked up a stone/fragment and the vacuum stopped. Appears to be a rock of some kind. 800cpm.

Videos on \\trwindata\groups\remote handling\Videos\2014\2014_2A3window folder, videos 3 and 4.

Continued with vacuuming inside wall penetration to remove debris. Changed filter bag in nilfisk vacuum, left old filter in place however vacuum continues to stall after >5min use. Vacuum gets quite warm before self shutting off. Debris seems to be falling back down on to joint if vacuum is turned off.

Took some screenshots of video showing removed debris and rust(?) on beam pipe. Video located on remote handling group folder.

Will attempt to remove clamp tomorrow.

Today:

1) Vaccumed top and around clamp. Disconnected clamp from flanges and removed from beam line. Currently bagged and stored in metal pail next to target pit area. Clamp is 500 µSv @ 1/2 m.

2) Removed 2A3 window from beam line. Pried apart joint from top of target station using pole tool. Window is 95 mSv o.c. 5000 µSv @ 1/2 m. Currently stored in a metal shield & covered with lead blanket infront of spent target vault.

3) Did preliminary clean of tank side flange with cotton glove. See videos in RH group folder. A mark still remains on flange.

4) Installed dust cover over tank flange.

5) Removed old leaking beam tube + support from wall penetration. Currently stored in 2A tunnel, both pieces are bagged. 500 µSv @1/2m, 12000 µSv o.c. Took 2 vials/samples of the deposits inside the plastic piping surrounding the beam tube supports. Material appears to be crystalline and moist.

Today:

1) Cleaned flange with methanol and cotton glove, appears to be clean.

2) Installed new beam tube and cradle into wall penetration, cradle was setup same as previous cradle (which is now removed). On advancing into position, the flange on the flexible bellows appears to get stuck on the spigot of the fixed tank flange. Removed and measured slot, is undersize (.373-.374), will re-machine slot for spigot.

3) On visual inspection, ITE tank flange appears to be warped in a location consistent with the clamping area of the window clamp. Further investigation is required.

R. Kuramoto and A. Laxdal measured the distance from the 2A tunnel to the tank flange of ITE. The new fabricated beam pipe with bellows was used to gauge the distance to the tank flange; The flange face of the beam tube was butted up to the tank flange and the beam tube was marked at the plane of the wall. A metal rod was used to gauge the distance to the tank face using the same method.

From the inside of the tunnel wall:

- To tank flange: 45 5/16"

- To ITE vacuum tank face: 49"

See attached PDF.

Today:

1) Installed new cradle and shortened beam pipe section in wall penetration.

- Removed tank dust cover from flange and cleaned

- Held flange faces together from 2A tunnel side to check alignment, slightly biased to the East axially and a small gap present in the top when resting

2) Prepared new 2A window

- Connected preswaged  (1/2 turn) swagelok nuts to the existing copper lines in the target hall, 1/4 turn from finger tight, 3/4 turns total

- Leak checked cooling lines with pressurized air at 75psi and snoop, no leaks were found at the joint

- Grooves were cleaned and helicoflex delta seals were installed with vacuum grease used in the periphery to hold ring in window, applied at 6 points every 60deg

3) Window installation

- Lowered window into position by cooling lines

- Window located into tank flange first then slid beam pipe towards it, capturing the window with seals

- Lowered clamp into place in hole

4) Clamp installation

- Lowered clamp into access hole and started closing clamp with steel RH drive bar

- torqued to 50 ft-lbs collar gap was still ~8"

- Increased torque to 60 ft-lbs then 70 ft-lbs stopped closing of clamp when the displacement did not change between the stop ring and clamp yoke

- It was decided not to continue to close this clamp, more assessment may be necessary

6) We will attempt to pump on the seal in its current configuration, tools have been removed.

Helium leak checked 2a3 window after installing using remote line:

- There was a leak found between the target and entrance module at the target pit, rate of 9E-6 atm-cc/sec.

- One test performed with the remote helium line to the window. There was a response but the leak detector was located above the window access channel, drift cannot be ruled out.

- 3 more tests performed with vacuum group, with leak detector relocated farther away from ITE and isolated with plastic. 2 tests using remote line had no response. One test done with a wand through 2a3 wall penetration had a response of 3.2E-9 atm-cc/sec (not using remote line).

Vacuum group (D. Yosifov) comments that due to the much larger leak at the top of the tank he cannot say with confidence the response seen is a leak at the window (due to leak at top) but if there is, a tolerable leak rate.

On drawing ITA6008 for the Encole 0.5" ceramic standoffs there is a note to match pairs of ceramics to within +/-0.001". This step was missed on the current build of TM2 source tray (ceramics were not measured).

Measured the lengths of the rest of the ceramic standoffs in inventory and they range from 0.5035" to 0.4950" in length. The ceramics have been sorted by length and grouped into bags.

Transfered the 2A window from the ISAC Storage Vault to the Cyclotron Vault Tunnel Storage area. RPG storage form attached.

Travis Cave wrote:

The 2A3 window now has a lid, and lift yolk on it and it has been installed in the spent target vault in spot 2A. The lid is a normal unmodified and has no sealant on it.

The pail containing window was transferred from the Storage Vault to the Cyclotron Vault Tunnel Storage 2017 Mar 24. It was placed in a brick bunker along the north wall and marked with item #1434. RPG storage form is attached.

Highest field measured at 0.5 m was 3000 uSv/h with an estimate of 4000 uSv/h on contact with the pail. Pail exterior was not contaminated. See attached storage form for details.

 

After re zeroing alignment telescope to master jig and adjusted parts into place:

Orientation: X = Left -, Right+; Y = Up +, Down -

Front wire target

X = 0.000, Y = 0.000

Rear wire target

X = 0.000, Y = +.008" (high)

All fasteners torqued to specification, steerer housing and assembly not installed yet. Weight of steerer assembly might cause rear to sag into place. Otherwise may attempt to split difference between the front and rear elements (alignment is on an angle in the horizontal vertical plane.)

Spare source tray build continued.

Initial alignment check in the morning:

- Target mounting plate target: Horizontal: .002, Vertical: -.002

- Ground electrode (bore) target, with un-clamped target: H 0.0 V -.003

- Ground electrode target (with target clamped): H: 0.0, V: .010

@14:10: sighting Master target position WRT sighting axis, calculated using the edges of the brunson target center circle edges calculated to center. Target circle is .02" in diameter.

- Master target mounted with slight finger torque.

- Front of master target, H .002 V -.002

- Rear of master target, H: 0.0 V: .005 (circle target is .020" in diameter)

- Rear of ground electrode target, H: .002, V: 0.011

@14:49: Replace mount plate target.

- Target mounting plate target: H -.001, V .001

- Ground electrode target: H .002, V .011 (rear target was rotated 90 deg from in the morning as a check)

@15:21 Steerer cone re-alignment.

- Undid the six screws holding the steerer cone and steerers to the aluminum flange and adjusted cone tip to RIB axis. The ground electrode bore was deemed not to be adjustable to the RIB axis with the current build order.

*Steerer cone assembly torque is 23 in-lbs

- Steerer cone target, H: .001, V: 0.0

- Steerer cone target, H: .002, V: .002 (after rotating target 180 degrees)

@15:30 Replaced target mounting plate target.

- Mounting plate target, H: .001, V: -0.001


Will go ahead and finish mounting components to mounting plate and final check the alignment after.

Source tray is complete for brazing, gas line bracket is currently missing but can be made in parallel with tube bending operations.

Source tray water lines to be fabricated according to ITA6144 drawing set.

- Alignment between target mounting plate and steerer cone is holding within .002"

- Aluminum soldering jigs are installed in place of the ceramics with fasteners only torqued just past "finger tight".

2A2 window has been removed from ITW and beamlines has removed the beamtube from the penetration. The penetration has been sealed with plastic sheeting and duct tape to maintain the ventilation depression between the 2A tunnel and the Target Pit.

Window is currently stored in a lead flask in the target hall. Window fields are 26 mSv/h OC, 1.2 mSv/h at .5m. There is a 10 uSv/h field outside the flask with the window inside it.

Clamp is currently sitting bagged in ITW Station Pit, it is quite corroded.

Tank flange was video inspected but still needs to be cleaned, currently there is a slip on dust cover over the flange to protect it.

Work will resume after the nuclear ventilation comissioning is completed.

Vacuumed out remainder of debris from the wall penetration, removed cradle and checked condition. Down stream support bracket sees advanced stages of material loss (OBO 20-30% loss). See attached photos.

RPG reports that the removed beam tube has 15k CPM on the interior of the beam tube.

Tank flange was cleaned as per 2009 repair report, looks OK. Video capture of flange inspection attached as .zip file.

.03" shim was inserted into the clamp indexing block.

Yesterday we installed the 2a2 window, the drive screw was torqued until 70 ft-lbs and we stopped, the yoke is not fully closed to its hard stop with roughly 7/8" to 3/4" still to go. Similar to identical conditions to 2a3 beamline window install, see https://elog.triumf.ca/TIS/RH-ISAC/647 for that install. Otherwise clamp looks centered and installed correctly.

Concerns with the cooling lines for the window WRT to the base of the shielding plug: There is no jog bend indicated on drawings for the transition of the window cooling lines from beamline center to the corner of the shield plug penetration. See photo for cooling line position on initial removal of shielding plug. It was decided to not add a jog for the shield plug and to carefully reinsert it being mindful of the cooling lines.  The shielding plug has a chamfer on the corner to allow the cooling lines to be routed to the top.

A new beam tube cradle is being manufactured where the old one will removed and the new one swapped with the beam tube in situ. Both sides of the window still need to be leak checked.

Attached alignment check notes after brazing and fabrication.

First page lower half shows establishment of baseline using master jig

Second page top half shows the alignment of the target mounting plate jig and the steerer cone aperture.

Second page bottom half shows alignment of the master target jig. Master target jig needed the 9 pin and heat shield locating features removed to seat the target correctly.

Overall, source tray assembly sits .006" high on average (min .003", max .010"), .003" to the left with respect to ion beam axis.