Post Irradiation Examination

October 9, 2024 - Aaron Tam 

Goal: Training (First PIE by Aaron), Characterize any anomalies 

Notes:

• Overall the target looks exceedingly clean with only some discolouration on the copper behind the target tube, and multipin cable insulation. 

 TiC#7 Target Removed from TM4. - Photos attached 

TiC#7 Currently sitting in SHC waiting for disposal 

TiC#7 failed after two weeks of operations - measurements in the electrical room indicated that the negative side of the CHT was broken (35kOhms to the rest of the target). This was likely due to a large number of proton trips during this target run. At every trip I could see the CHT voltage getting higher and more unstable. This cahnge in voltage was reflected in the unstable anode current and fluctuating RIB beam intensity, as a direct result of the fluctuating power on the CHT. The break was confirmed in PIE, loosening the screws caused the target container to come off without the cathode. Otherwise nothing unusual was seen. The anode wire connections seem very robust, dragging the target around with the multipin disconnected, flipping it up and down, etc and the anode wire stayed attached. Though we saw lots of outgassing on this target, things looked the normal level of dirty. There was no buildup between PE and EE.

PIE on TiC#6 was done in the NHC. The target assembly looked brand new when we took it out, no heating spots or deposits (pictures on docushare). Online we measured a 400kOhm connection between TGHT-TBHT-COIL to HV common (TGHT and COIL shorted in TM2 service tray) and anode was unstable above ~300V. After the module move and before the target removal David found TGHT-TBHT-COIL was a dead short to HV common and the anode was at 39kOhms to HV common.

1. Wanted to see if the TGHT-TBHT-COIL short was on the COIL. Measured with ohmmeter the COIL lines to HS and got about 700Ohms. But with the target lying down the COIL lines drop and touch the heat shield so to do this measurement Chad had to lift the lines, which could cause them to touch something else. So not sure how reliable this measurement was. It jumped around a lot, saw 0L occasionally.

2. Measured both target legs and tantalum gas line to HS, got about 5kOhms repeatedly using the ohmmeter.

3. Meggered across the gas line insulator to the gas line going into the target and got open circuit at 250V, so the gas line wasn't coated.

4. Target container looked vaguely red in the areas where the target material was, otherwise still no deposits on the inside. The container was not overly crystalized as seen on the legs and end caps.

5. Some sparking marks on the EE and some slightly asymmetric deposits

Continuing Aug. 22 2023:

6. Found what looks like a hole in the insulation on the COIL, maybe the cause of our short? Found a corresponding line mark on the copper plates that hold the coil down but not sure if it is related. Pics on docushare.

7. Grid looks perfectly new. Where was that current going?

8. Copper plates that hold coil were loose and bolts that hold coil in just fell out as well.

9. What can be seen of the anode wire looks good.

The TiC#5 post irradiation inspection was done on Wed. June 14 and Mon. June 19. This target didn't have any obvious issues but it didn't produce much beam. The inspection revealed that the container was quite embrittled and showed significant damage, though it was not broken. The FEBIAD grid looked fine, despite the large anode current draw (indicating that current was flowing elsewhere). The gas line looked fine though the gas injection to this target looked as if it wasn't connected. But there was a plug on the unused line, so it must have been correct. No other obvious signs that would explain the poor performance. Pictures are can be found here https://documents.triumf.ca/docushare/dsweb/View/Collection-37913

TiC#4 has been installed onto TM3

TiC#3 sucessfully installed and ready for leak and electrical check.

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.

The old thermocouple wire has been sucessfully removed from the module.

Thanks Bevan, Travis and David.

The bad thermal motor protection relay for the crane has been replaced with a new unit. Crane was tested in pendant(local) operation and all drives worked.

to reduce the radioactive shining from  SHC Ta# 40 target.

The yellow steel plug is put on SHC in TH. The spent target is inside the SHC.The field around the SHC area in TH is so high that we have put it on. It will be moved out on this Thursday just before the spent target move. 

ThO#1 has been removed from TM1 and placed into the plastic dissection box.

Containment box cover has been reinstalled as per usual.

ThO#1 has been installed onto TM1 and is ready for leak and electrical checking. High current fasteners torqued to 130 in lbs.

The target hall has been locked-out as per Document-70039.

Forced IG1, IG1S and IG2 to switch on BIAS power supply

Wednesday, July 12, 2017, 11:53: 70 kV at 0.16 mA

2 sparks observed shortly after 70 kV was reached

Wednesday, July 12, 2017, 12:59: No sparks for the last hour.

BIAS power supply off. Forces removed.

 I have tested all of the compressors for TCS. All are operational and cycled as they should. 

Shorted TGHT with new high current connector assembly and heated to 600 A. Temperature measured on half way point on cable ~ 70 deg C and on connector ~60 deg C at 600 A, 45 / 40 deg C at 400 A. Target Hall locked out during test

Friday, November 06, 2015, 14:35: Roughing

Turbos was started around 4pm. Later it was found that the manual valve for the two turbo pumps on the service cap was closed. The valve was open and pumping resumed. The roughing vacuum was high and increased into Saturday morning. The vacuum system was switched off on Saturday.

Purged MP1 using the purging function. Performance recovered. Started rouging.

Monday, November 09, 2015, 09:18: Started TP1S

Monday, November 09, 2015, 09:22: Started TP1 and TP2

Monday, November 09, 2015, 09:33: All 3 turbos at speed

Leak found on F/T for multipin connector

Tuesday, November 10, 2015, 09:53: stopped turbos

Tuesday, November 10, 2015, 16:53: Roughing

Tuesday, November 10, 2015, 18:24: TP1S started

Tuesday, November 10, 2015, 18:30: TP1 and TP2 started

Tuesday, November 10, 2015, 18:41: All 3 turbos at speed.

Thursday, November 12, 2015, 08:30: Purged backing pump using purging function. Vacuum in backing line recovered to previous value. 

Module connected for HV testing. No target heating possible. All F/Ts tied together to HV common. EZL connected.

Friday, November 13, 2015, 11:20: Started water package

Friday, November 13, 2015, 11:52: 1kV on BIAS and 1 kV on EL

Friday, November 13, 2015, 12:54: BIAS/EL 10 / 5 kV

Friday, November 13, 2015, 12:59: BIAS/EL 15 / 7.5 kV

Friday, November 13, 2015, 13:04: BIAS/EL 20 / 10 kV

Friday, November 13, 2015, 13:08 : BIAS/EL 22 / 11 kV. Some sparks.

Friday, November 13, 2015, 13:17: Sparking at 22.5 kV. Had to return to 20 kV to recover. Back at 22.5

Friday, November 13, 2015, 13:21 : BIAS/EL 24 / 12 kV. 

 Friday, November 13, 2015, 13:27: Heavy spakring around 24.5 kV. Had to return to 20 kV to recover.

Friday, November 13, 2015, 13:31: Attempted to increase voltage again. Sparking started around 23 kV. Had to lower to 20 kV.

Friday, November 13, 2015, 13:36: 9 sparks for the last 5 min.

Friday, November 13, 2015, 13:45: Spark rate reduced, but multiple sparks encountered again at 20.5 kV. Reduced back to 20 kV

Friday, November 13, 2015, 13:50: Increased sparking at 20 kV. Had to lower to 18 kV

Friday, November 13, 2015, 14:07: Back at 20 kV

Friday, November 13, 2015, 14:13: BIAS and EL off

Monday, November 16, 2015, 08:18: Fault on chiller. Reset chiller unit on the roof.

 The BIAS voltage was brought up to 70 kV today and held there for 1h. No sparking observed.