TM2 was moved and connected in ITW yesterday afternoon. After roughing down, ITW turbo pumps are started. ITW TP4 can not be started to full speed. ISAC ops kept it at low speed mode with less than 1.0A current draw on pump. ITW IG1s shows red as well. I will take a look on them today when beam is off.

  Chad and I did the helium spray leak check on TM2 GE and MSP water lines at SHC this morning. We confirmed the GE leak on water blocks. We can not found the MSP leak by using the helium spray since its leak rate in TCS is much smaller than GE leak.  The leak check process are as below:
Leak detector are calibrated before the check.
GE lines : Base leak rate 0.0 X E-9 atm.cc/sec, base pressure 0.0 XE-4 torr.
Chad sprayed 5 psi helium to GE lines soldering joints  for 5 second, no response on leak detector.
Chad sprayed 5 psi helium to GE lines water blocks( between blocks seal surface) for 5 seconds, Leak detector response to 8 XE-9 atm.cc/sec right away.
Chad sprayed  5 psi helium to GE lines soldering joints for 5 seconds again, No response on leak detector.
Chad sprayed 5 psi helium around the source tray and to vacuum duct for 5 seconds more, No response on leak detector.
MSP lines: Base leak rate 0.0X E-9 atm.cc/sec, base pressure 0.0 X E-4 torr.  Chad did same thing as he did on GE lines. no response on LD. Chad repeated the test and prolonged the spray time to 10 seconds, No response.
The conclusion: It is pretty clear we have a leak on GE line water blocks seal.  MSP lines leak could not be found by helium spray in SHC since it is a small leak.
 

TM2 has been helium pressure tested in ITW and TCS. They are both tested with 70psi helium, each circuit for 3minutes. 

The leak detector base leak rate: 0.0X E-9 atm.cc/sec, base pressure 0.0 xE-4 torr  for both ITW and TCS. The test results are:

 2016-11-24: Checked again and added result into this elog.  No essential change has been found. MSP still has the biggest leak rate. David

Spark between HV cover vertical mesh plate and HS 60KV  bias connecting clamp 90degree angle at 55 KV on TM2 top. HV cover is removed to test above  55KV. The spark triggered TH and SHC ventilation secondary alarm.

Starting HV tests on TM2 with 50uA of protons.

Tuesday, August 06, 2019, 03:37 : Ramping up 500V every 2mins or so, couple of sparks, then consistent sparks at 34kV. No vacuum response on IG1 for any sparks, even though the current spikes from around 40uA to 1300uA. Brought it down to 28kV to stop sparking. See a response on the EZL frequently.

Tuesday, August 06, 2019, 05:24 : Going above 30kV proves very difficult, lots of up and down, frequent sparks, still no vacuum response. Still seeing an EZL response.

Tuesday, August 06, 2019, 05:58 : Up to 31.5kV on bias, 1046V on EE and 15kV on EZL.

Tuesday, August 06, 2019, 06:50 : Controls are being sticky - not responding well.

Tuesday, August 06, 2019, 07:25 : Sat at 32 kV > 20mins with 2 sparks

Tuesday, August 06, 2019, 08:03 : lots of sparking at 36kV, went back down to 35kV. Current draw is 50uA.

Tuesday, August 06, 2019, 08:10 : lots of sparking after 9 mins at 35kV, had to turn it down to 34kV

Tuesday, August 06, 2019, 08:11 : Still sparking at 34, down to 33

Tuesday, August 06, 2019, 08:31 : At 33kV, sparked twice in 20mins and was going for another when the protons went off.

With protons off, the bias current dropped quickly from 66uA to 40uA and raising the bias to 40kV was not difficult.  Later bias up to 50kV. Still no conclusion on if the sparking was inside or outside of the vacuum. No vacuum response seems to indicate outside, however the influence of protons would indicate inside. To be investigated visually when TM2 comes to the HC.

Chad and I did  leak check on TM2 HS line at SHC yesterday. Base LR 0.0XE-9 atm.cc/sec.   No response on LD. during helium spray.   Today , I did helium pressure test at TCS. base LR 0.0xe-9atm.cc/sec. applied 70psi helium for 3 minute. leak rate slowly climbed to2.2 Xe-7 atm.cc/sec ate stopped there.  The result is close to before.

TM2 HS line helium leak check is done. leak detector base LR 1.8xE-8atm.cc/sec.  helium pressure 70 psi. 5 minutes test. no change on LD leak rate.    I spray lots helium to gas line adaptor and fittings. No leak.has been found  at this base leak rate level.  Since the TCS MP1 has some  issue ,this time the base leak rate on LD only can get to 1.8Xe-8 atm.cc/sec at this moment instead of 0.0xE-9.  The low E-8  level is not perfect, but  i  have no concern on it.

 An electrical check was done at SHC for TM2 with FEBIAD SiC #42 Target. 

 A Test Febiad Target was installed and checked at SHC. 

TM2 is now in the hot cell with the containment box off for inspection and eventual blank off off the water blocks.

Upon initail inspection the status (fron a hot cell point of view) is:

-Water block jig is equipped/on

-There is a thermocouple line that will need to be removed

-TM2 requires a new front containment box cover - already manufactured and waiting for installation

The containment box was taken off TM2 in preparation for installation of a new coil line isolator.

ITA6272 and ITA6273 have been received from the Scintillator Shop.  ITA6274 should be ready by the end of today.

TM2 coil line R,U has been vacuum leaked check at the hot cell and has passed with no response from the leak detector.

First thing this morning the hot cell was "cleaned up" in preparation for the return of TM2 for attempted verification and locating of leak on R/U coil circuit.

Containment box has been removed and front cover reinstalled to provide some modicum of shielding form the entrance and exit windows. Box was placed at an angle in the corner to try and minimize line-of-sight with potential worker(s).

Did notice some funny discoloration of both sides of coil water block "R" as seen in attached picture.

SEE ATTACHMENTS. EVERYTHING IS GOOD.

Containment box has been removed and the blank off from circuit D has been removed for inspection of both the blank off and water block sealing surface.

Firday, November 8 all water blocks (excluding I and K) were blanked off and vacuum leak checked. No responses were found. (First Picture)

I and K could not be blanked off without removal of the water block jig. Also, I dropped one of the blank offs onto the table, so one line could not be blanked off until a new clean blank off was inserted into the cell. In addition, there was still reminace of a bolt in block Ias it aslo could not be removed until the water block jig was removed.

Tuesday, November 12 a new blank off was put into the cell. The water block jig was removed, which was very easy, confirming documentation from installation (in 2008?) that it fit very well / the blocks were bent and soldered to the jig very carefully.

Screw was removed from I and both I and K were blanked off and vacuum leak checked. No response. (Second Piccture)

Containment box was re-installed and module ready to move to the conditioning station by noon.

The water blocks soldered to the TM2 cooling lines (see Ref. Assy. ITA6144) were inspected.

See attached inspection reports and drawings.

It was found that only 18% of the seal groove diameters and 55% of the depths were in spec.

The source tray must be tested on the test stand with c-seals to ensure that these blocks will seal properly on the module.

Hello all,

TM2's first performance in the Conditioning Station with the new source tray was not great, with sparking and HV degradation beginning to occur at 30kV:
https://elog.triumf.ca/TIS/RH-ISAC/1039

This is perplexing, because the module without the source tray performed well at the TCS:
https://elog.triumf.ca/TIS/RH-ISAC/829

AND the new source tray performed well at the test stand (i.e. not inside the module):
https://elog.triumf.ca/TIS/Test-Stand/447

Upon inspection back at the Hot Cell last week after the failure, David Wang was observant enough to notice that one of the steerer coax wires (ground plane) was essentially touching one of the FEBIAD gas lines (HV plane) in the new source tray installation (photo attached).  Closer inspection by a group consisting of Anders, Alex, and myself revealed some apparent tracking and damage to the wire sheath.
https://elog.triumf.ca/TIS/RH-ISAC/1045

We believed at this point that the bad HV performance of TM2 was due to this problem.  The wires were originally arranged loose as it was believed it would be easier to install them in the Hot Cell this way.  However, it turned out to be a bad decision, as the wires at ground ended up becoming stray and touching the HV surface.

To correct the problem, the old wires were removed, and a new steere wire bundle was made using a PEEK material sheath.  This new sheath bundle was installed over the last day or so.  The penning gauge wire was kept separate from the steerer wire bundle.  You can see the new wire bundle and penning gauge wire in the attached photo, now with a healthy clearance to the FEBIAD gas lines.

Chad has been instructed to re-install the Einzel lens wire, install the new ZrC target, and replace the containment box in preparation for transport back to the TCS for another HV test.  If anybody would like to see the source tray today before ~3pm, I have asked Chad to wait for my final OK to put the containment box back on the module.

I apologize for this problem.  We are hopeful the solution we have installed will improve the HV performance.  Much work over the last 2+ years was put into building and installing this source tray by many contributors inside and outside of Remote Handling, and we want this module to succeed more than anybody!

Thanks and best regards,

Grant

The HV  cover is installed on to TM2 after the connections. The HV key is returned back to B2 level. The TCS Faraday cage is locked.