After a great struggle with the water block jigs, the TM3 source tray was finally advanced fully into the service tray and all water blocks were connected and torqued to spec in the hot cell by Chad Fisher.

Notes and description of problems encountered during the installation:

- The water lines for the optics tray interfered with the module-side water block jig, and had to be bent out of the way to clear while advancing the tray (see attached photos)

- The water block jig on the source tray side was too low relative to the module side, and had to be eventually unbolted completely from it's mounting bracket in order to raise it up into alignment

- A piece of aluminum plate was placed under the jig, and the pneumatic table was raised in order to move the jig upwards

- After many repeated attempts to engage the blocks by pressing the jigs together, it was discovered that some of the blocks had rotational misalignment with their respective counterparts on the module side, preventing the pins from engaging properly

- By looking through the bolt holes on several of the blocks, it was possible to determine which direction they had to be rotated

- Chads polishing tool was used to apply some torque to rotate the source-tray-side water blocks slightly so proper alignment of the pins could be achieved

- See the attached photo which indicates which blocks had to be rotated (blocks 5, 6, 9, 10, and 11)

- The blocks had the bolts installed and were also torqued in the numbered order shown in the attached photo

Next steps are to remove the water block jigs, re-connect the loosened brackets for the remaining water lines (entrance window, optics tray), re-install the containment box and associated VCR connectors, video inspect, and leak check.

While continuing on the TM3 Rev 3 source tray installation, Chad noticed today that one of the steerer wires is broken and has come out of the thermocouple-style connecter block (see attached photos).

From drawing ITA2826 (Rev D02 attached) it is likely that this is for either the "upper" or "right side" steerer plate.

Today Chad finished making all connections to the new source tray, except for:

- steerers - broken wire, must be repaired at a later date

- IMG gauge - bracket required, old bracket thrown out with previous tray by accident, see ITA3301, must be installed at a later date

- entrance window - the window lines on module side were left blanked-off for leak checking, containment box must be removed in the next few days to complete steerer repairs so these lines were not connected to save work from having to be repeated

The containment box was replaced, and TM3 was moved to the CS for pump-down and leak checking (see other e-log).  David reported at 6:15 pm that the turbos were turned on at the CS and the vacuum looked normal (so far).

As stated above, Chad realized today that he had thrown out the old IMG gauge bracket with the previous source tray, and a new one must be manufactured.  The assembly is described by ITA3301.  Three components must be manufactured (ITA3302, ITA3303, and ITA2673).  A stock split-ring clamp for ITA2673 (MDC #716001) was graciously donated by Dimo Yosifov.  Grant Minor submitted a work order to the machine shop today for 2 each of ITA3302 and ITA3303.

Target Module 3 with no target, and a partially-installed Rev-3 source tray (no steerers connected, no IMG connected, entrance window lines blanked off on module side and not connected to containment box) was transported successfully to the Conditioning Station by Travis Cave and David Wang at around 4pm today.  David attached the vacuum system for start of pump-down to prepare for leak checking.

David Wang started a helium leak check on TM3 at the CS this morning.

David will create an e-log once his check is complete, but here are the preliminary results:

- target oven +/- OK

- mounting support plate OK

- ionizer tube heater +/- OK

- extraction electrode OK

A large leak was found in the heat shield circuit:

- The module pumped down with the leak rate stabilizing at 4.8xE-9 atm.cc/sec
- 60 psi helium was applied to the heat shield fitting on the right side of the Y-shaped connector (see attached sketch, each side of the "Y" is separated by a face to face metal contact only, i.e. no o-ring seal separates supply and return water)
- The maximum leak response was detected in 10 seconds, with base pressure rising from 2.0E-2 torr to 2.8xE-2 torr
- The helium was vented from the line by using an allen wrench to open the valve on the water quick-connect (see attached photo)
- The module continued pumping down, and after some time, the allen wrench was used again to open the valve, but air rushed inside, indicating vacuum was being drawn inside the water line through the leaking interface
- As the module continued to pump, this vacuum vent air rush inside the water line could not be reproduced by opening the valve again with the allen key

The module is currently pumping down at the Conditioning Station. We will leak check the remaining lines tomorrow with whatever base leak-rate we have achieved, and then move TM3 to the Hot Cell for further diagnosis.

TM#3 with no target has been moved from the conditioning station to the south hot cell. The fields observed around the containment box of the module ranged from 0.80 mSv/hr to 1.8mSv/hr..

A huge leak had been found on HS circuit during 60 psi helium pressurize test. Other circuits are free of obvious major leak at present .We will test them again once the TM3 is back to CS. See attachment for details

The heat shield circuit was pressurized with air (15-20 psi) and snoop applied to the water block joint and brazes. Bubbles formed at the joint between the two water blocks indicating that the leak is a c seal problem. Pictures attached but also on docushare Collection-11285.

chad fisher wrote:

The heat shield circuit was pressurized with air (15-20 psi) and snoop applied to the water block joint and brazes. Bubbles formed at the joint between the two water blocks indicating that the leak is a c seal problem. Pictures attached but also on docushare Collection-11285.

 Last night prior to this leak check the Heat Shield was pumped on and helium sprayed on the circuit. The pressure was 0.0 x 10^-4 Torr. The leak was traced to water block. response time was 2 seconds and went from 5.5 x 10^-8 to 1.6 x 10^-6 atm*cc/sec. There was also a response without spraying helium (drift from the nozzle). The results of this testing prompted the testing completed in Chads elog.

Bevan Moss wrote:

chad fisher wrote: The heat shield circuit was pressurized with air (15-20 psi) and snoop applied to the water block joint and brazes. Bubbles formed at the joint between the two water blocks indicating that the leak is a c seal problem. Pictures attached but also on docushare Collection-11285.  Last night prior to this leak check the Heat Shield was pumped on and helium sprayed on the circuit. The pressure was 0.0 x 10^-4 Torr. The leak was traced to water block. response time was 2 seconds and went from 5.5 x 10^-8 to 1.6 x 10^-6 atm*cc/sec. There was also a response without spraying helium (drift from the nozzle). The results of this testing prompted the testing completed in Chads elog.

 Please find attached some schematics which help illustrate the setup for this heat-shield circuit leak check.

 Today Chad entered the south hot cell on work permit 2013-08-29-3 to repair the leaking heat shield line. The heat shield line was removed from the module and the surfaces cleaned. New C seals and spring were inserted and the line re-attached. During this time Chad also installed the new vacuum gauge. Grant took video of this work and Keith some pictures. The video and pictures can be found on the M: drive (groups) in the RH folder. The total time taken was ~ 25 minutes. The line was then pumped on and the block was sprayed with helium. The pressure and leak rate started at 0.0 x 10^-4 Torr and 4.0 x 10^-8 atm*cc/Sec. When the helium tank was opened there was an immediate response with the leak rate climbing to 2.7 x 10^-7 atm*cc/Sec. It then stabilized at 2.0 x 10^-7 atm*cc/Sec and was sprayed with helium. Response time was ~2 seconds the leak rate climbed to ~2.3 x 10^-5 atm*cc/Sec the pressure also increased to ~3.0 x 10^-3. The leak detector cart was left attached for another 1.5 hours but still was not able to stabilize in the 10^-9atm*cc/Sec range. 

Bevan Moss wrote:

Today Chad entered the south hot cell on work permit 2013-08-29-3 to repair the leaking heat shield line. The heat shield line was removed from the module and the surfaces cleaned. New C seals and spring were inserted and the line re-attached. During this time Chad also installed the new vacuum gauge. Grant took video of this work and Keith some pictures. The video and pictures can be found on the M: drive (groups) in the RH folder. The total time taken was ~ 25 minutes. The line was then pumped on and the block was sprayed with helium. The pressure and leak rate started at 0.0 x 10^-4 Torr and 4.0 x 10^-8 atm*cc/Sec. When the helium tank was opened there was an immediate response with the leak rate climbing to 2.7 x 10^-7 atm*cc/Sec. It then stabilized at 2.0 x 10^-7 atm*cc/Sec and was sprayed with helium. Response time was ~2 seconds the leak rate climbed to ~2.3 x 10^-5 atm*cc/Sec the pressure also increased to ~3.0 x 10^-3. The leak detector cart was left attached for another 1.5 hours but still was not able to stabilize in the 10^-9atm*cc/Sec range.

 Also of note is that Chad received a full days dose and that when the plastic was surveyed there were ~150 counts found on it.

Bevan Moss wrote:

Bevan Moss wrote:  Today Chad entered the south hot cell on work permit 2013-08-29-3 to repair the leaking heat shield line. The heat shield line was removed from the module and the surfaces cleaned. New C seals and spring were inserted and the line re-attached. During this time Chad also installed the new vacuum gauge. Grant took video of this work and Keith some pictures. The video and pictures can be found on the M: drive (groups) in the RH folder. The total time taken was ~ 25 minutes. The line was then pumped on and the block was sprayed with helium. The pressure and leak rate started at 0.0 x 10^-4 Torr and 4.0 x 10^-8 atm*cc/Sec. When the helium tank was opened there was an immediate response with the leak rate climbing to 2.7 x 10^-7 atm*cc/Sec. It then stabilized at 2.0 x 10^-7 atm*cc/Sec and was sprayed with helium. Response time was ~2 seconds the leak rate climbed to ~2.3 x 10^-5 atm*cc/Sec the pressure also increased to ~3.0 x 10^-3. The leak detector cart was left attached for another 1.5 hours but still was not able to stabilize in the 10^-9atm*cc/Sec range.   Also of note is that Chad received a full days dose and that when the plastic was surveyed there were ~150 counts found on it.

Today Chad entered hot cell again and removed the HS module side and Junction Block Wiring Harness (module side). In addition to this he blanked off the module side HS line. It took Chad 16 minutes to perform these tasks and he received a dose of 0.20 mSv bringing his total to 0.84 over the last 2 days. After exiting the hot cell Chad completed a leak check on the module side. The line pumped down to the limits of the leak testing cart 0.0x10^-4 Torr and 0.0x10^-9 atm*cc/sec and there was no response. A video of Chad in the hot cell can be found in:

M:\remote handling\Photos\2013\2013_tm3_source_tray_refurb

This afternoon was spent surveying the anteroom and receiving teaching from Chad as to how to be a hot cell operator. There was little in the way of contamination ~150 counts near the HC door and ~50 counts on the surrounding floor. The wiring harness has a field of 900 uSv/hr but is suspected most of that is coming from the aluminum steerer bracket. 

 September 3rd

David Wang and myself lowered the leak testing cart into the Ante room and prepared the ante-room for the leak testing of TM3s line. David and Grant then entered the anteroom and inspected the old c-seal and leak tested the the heat shield line. The line pumped down to the lower limits of the leak detector and there was no response from the cart. A presentation with the results of the C-seal inspection results was completed by Grant Minor and email for a design review held on the 4th.

September 4th

David Wang and myself removed the leak detector and surveyed the anteroom and cart. The following results were found with the high spec gamma detector.

Leak Detector body and cart 0 

Leak Detector wheels 200 cpm

Floor off of plastic 300 cpm (there was contamination before)

Plastic in front of HC opening 2000 cpm

Working table after plastic was removed < 50 cpm

Tool box < 50 cpm

First tacky mat 2500 cpm

Second tacky mat 200 cpm

outside of door tacky mats 0 cpm

David then laid fresh plastic on the floor around the HC opening and covered the exposed floor as well.

Following this Travis and David measured the lengths of the wiring and attempted to separate the wiring harness from the Ultem block. It was found that the block was pinned and could not be separated, a new block will need to be made. The measured the following lengths:

Steerering - 26" to 27"

Collimator - 32" - 33"

PNG - 60"

Today Maico measured the thickness of three indium-plated inconel c-seals, presumably Ultra-Seal P/N 50606.  These seals had NOT been in the Hot Cell.

Uncompressed (new) "thin" c-seal

OD .435"

ID .300"

Thickness .094"

Uncompressed (new) "thick" c-seal

OD .438"

ID .280"

Thickness .096"

Compressed (used) "thin" c-seal (Beginning of Life bench test compression only, not long term compression)

OD .438"

ID .294"

Thickness .079"

Maico commented that he measured the thickness of a few other compressed "thin" c-seals and they all had .079" thicknesses.

The seal space when the blocks are bolted together (shown on ITA2342 Rev F) should be .070" (steel insert CB) + .002" (recess on module side)  + .002" (recess on source-tray side) = .074"

Thus the compressed seals seem to have .079" - .074" = .005" spring-back.

C-seal drawings from Ultra-Seal and Garlock in chronological order from Guy Stanford's design file are attached.  Guy's whole design file is also attached for reference.

Yesterday, Grant entered the Ante Room with David Wang to visually inspect the two sets of failed c-seals from the Heat Shield circuit, to remove the second set from the Heat Shield water blocks, and to leak check the heat shield circuit with o-rings and a water-block-to-leak-detector fitting.

Some photos of the inspected seals are in the attached design review presentation.  Some unusual marks were observed on both sets of failed seals.

The heat shield lines and water block assembly leak checked successfully to the bottom of the leak rate range ("UNDER" ~1x10-9 atm cc / sec on the Varian 979) with a great flood of helium on all joints with no response anywhere.

 Today Maico completed the new leak testing tool and blank off. He tested them with C-seals without springs and all was leak tight. He then inspected the crushed seals and noticed that there was an area that was crushed less on both seals (more prominent in one,  20130906_tm3sourtrayefurb_P1020975) and that this reduced crushed zone only appears on one side of the seal. This is similar to the failure seen on both sets of the heat shield lines. On the seal with the greatest change in crush zone the average crush zone was ~0.025 and the reduced crush zone was ~0.012". He inspected the leak tester and the blank off and determined they were within tolerance and that they had a total seal goove height of 0.074" which is nominal. New seals were selected and one had a visible dimple prior to crushing (20130906_tm3sourtrayefurb_P1020978)  and the other had some defects on the inside (20130906_tm3sourtrayefurb_P1020962). These defects were marked and crushed using the same leak testing tool and blank off. The seal with the dimple showed a reduced crush zone in the same area (20130906_tm3sourtrayefurb_P1030021) and the seal with the defects on the inside showed less or undetectable change in crush zone. Maico then inspected (20130906_tm3sourtrayefurb_P1020991) and crushed the "thicker seals" (more indium coating). When inserting the seals he noticed that they fit tight on the counter bore of the blank off. He then attempted to crush the seal to the point where the copper faces would touch (as design intent) but the seal locked. The gap between the 2 copper faces was measured to be ~0.001". This setup was leak tested and found to be leak tight. When inspecting the crushed thicker seals it was found that the material had actually been pushed sideways causing a lip to form around the crush zone (20130906_tm3sourtrayefurb_P1030003). Maico then fitted the wires for the testing of the module and the heat shield line. 

Bevan Moss wrote:

Today Maico completed the new leak testing tool and blank off. He tested them with C-seals without springs and all was leak tight. He then inspected the crushed seals and noticed that there was an area that was crushed less on both seals (more prominent in one,  20130906_tm3sourtrayefurb_P1020975) and that this reduced crushed zone only appears on one side of the seal. This is similar to the failure seen on both sets of the heat shield lines. On the seal with the greatest change in crush zone the average crush zone was ~0.025 and the reduced crush zone was ~0.012". He inspected the leak tester and the blank off and determined they were within tolerance and that they had a total seal goove height of 0.074" which is nominal. New seals were selected and one had a visible dimple prior to crushing (20130906_tm3sourtrayefurb_P1020978)  and the other had some defects on the inside (20130906_tm3sourtrayefurb_P1020962). These defects were marked and crushed using the same leak testing tool and blank off. The seal with the dimple showed a reduced crush zone in the same area (20130906_tm3sourtrayefurb_P1030021) and the seal with the defects on the inside showed less or undetectable change in crush zone. Maico then inspected (20130906_tm3sourtrayefurb_P1020991) and crushed the "thicker seals" (more indium coating). When inserting the seals he noticed that they fit tight on the counter bore of the blank off. He then attempted to crush the seal to the point where the copper faces would touch (as design intent) but the seal locked. The gap between the 2 copper faces was measured to be ~0.001". This setup was leak tested and found to be leak tight. When inspecting the crushed thicker seals it was found that the material had actually been pushed sideways causing a lip to form around the crush zone (20130906_tm3sourtrayefurb_P1030003). Maico then fitted the wires for the testing of the module and the heat shield line.

 Hello all,

As an addendum to Bevan's e-Log:

Maico also prepared eight (8) new retainer spring windings out of the .025" diameter stainless welding wire for the next seals that we will attempt in the Hot Cell and Ante Room

Maico, Bevan, Keith and I had a discussion about the bolt torque related to the c-seal and water block compression:
- It was found that not much torque is required to compress the "standard" design "thin" c-seals (Ultra-Seal P/N 50606 .001 - .0015 thou indium plating) - basically hand tight only with an allen wrench
- By hand-tightening the bolts with an allen key until the faces of the blocks came together, and then measuring the torque with a torque wrench, Maico discovered that about 8 foot-lbs = 96 inch-lbs (or 5/8ths of a turn past finger tight) was required
- The c-seals are fully compressed when the faces of the blocks are contacting... any additional torque applied is only to pre-load the bolts to ensure that they do not come loose due to temperature cycling and mechanical vibration
- Chad's Hot Cell torque tool is nominally set to about 168 - 180 inch-lbs (or about 14 to 15 foot lbs) based on an e-mail update from him 3-June-2013 - this torque is normal chart torque for a 1/4"-28 UNF SAE Grade 8 bolt pre-load of 3,250 lbs
- see http://www.imperialsupplies.com/pdf/A_FastenerTorqueCharts.pdf
- This amount of bolt pre-load torque may not be required if the bolts are SAE Grade 5.  I recommend at this point that the minimum possible pre-load torque be applied to achieve the chart recommended pre-load for the grade of the bolt, which should be investigated
- This is to ensure that we do not over-stress the thread inserts on the water blocks... if these inserts are damaged, we will basically render the service chase unusable and ruin the module

Cheers,

Grant

 The sealing surfaces of the module side heat shield water block were polished on September 9th in the morning using Chad's polishing tool with the following attachments:

- Scotchbrite pads  (30 seconds)  (after this step indium material from the previous seal was no longer visible on the sealing surface)

- 2000 grit sandpaper (30 seconds)

- Felt material with isopropanol (30 seconds)

- Lint free pad (30 seconds)

After the final step the surface was rinsed with isopropanol and air dried using canned air.  The water block blank-off was then installed with the manipulators, tightened until snug using the air ratchet, then tightened an additional 1/4 turn while the water block was gripped firmly using one manipulator.  The seal was leak checked and passed successfully.

TM#3 with no target has been moved to the conditioning station from the south hot cell.