Tuesday, May 07, 2013, 16:48

5 BeO pellets were made.  Each weights about 1.3 g (including org mass). 

A piece of Re foil (0.002" thick) is used as the under layer to protect the reaction between Be(g) and the Ta-boat.  (see Pictures)

Another layer of Ta-foil is used as the heat-shield to wrap around the Ta-boat.

The chamber was pumped down. 

TGHT will be ramped up to 600 A (~1360°C) at 0.2 A/min. The vacuum limit parameter was set for good vacuum at < 3.0e-5 Torr and bad vacuum at > 4.0e0-5 Torr.

The pressure, voltage and current will be closely monitored. 

If the Ta-boat survives, the TGHT will continue to ramp up to max 800 A (~1580°C).

Nikita Bernier wrote:

Tuesday, May 07, 2013, 16:48   5 BeO pellets were made.  Each weights about 1.3 g (including org mass).  A piece of Re foil (0.002" thick) is used as the under layer to protect the reaction between Be(g) and the Ta-boat.  (see Attachments) Another layer of Ta-foil is used as the heat-shield to wrap around the Ta-boat. The chamber was pumped down.  TGHT will be ramped up to 600 A (~1360°C) at 0.2 A/min. The vacuum limit parameter was set for good vacuum at < 3.0e-5 Torr and bad vacuum at > 4.0e0-5 Torr. The pressure, voltage and current will be closely monitored.  If the Ta-boat survives, the TGHT will continue to ramp up to max 800 A (~1580°C).

 Monday, May 13, 2013, 12:48

TGHT has been at 600 A for about 13 hours with stable very low vacuum (10^-7). See Attachment #1.

Temperature measurement has been lost on Saturday. Last measurement was was above 1350°C, at around 480 A.

TGHT was ramped down at 1 A/min.

The chamber will be vented later today. The pellets and the thermocouples will be inspected.

Nikita Bernier wrote:

Nikita Bernier wrote:  Tuesday, May 07, 2013, 16:48   5 BeO pellets were made.  Each weights about 1.3 g (including org mass).  A piece of Re foil (0.002" thick) is used as the under layer to protect the reaction between Be(g) and the Ta-boat.  (see Attachments) Another layer of Ta-foil is used as the heat-shield to wrap around the Ta-boat. The chamber was pumped down.  TGHT will be ramped up to 600 A (~1360°C) at 0.2 A/min. The vacuum limit parameter was set for good vacuum at < 3.0e-5 Torr and bad vacuum at > 4.0e0-5 Torr. The pressure, voltage and current will be closely monitored.  If the Ta-boat survives, the TGHT will continue to ramp up to max 800 A (~1580°C).    Monday, May 13, 2013, 12:48   TGHT has been at 600 A for about 13 hours with stable very low vacuum (10^-7). See Attachment #1. Temperature measurement has been lost on Saturday. Last measurement was was above 1350°C, at around 480 A. TGHT was ramped down at 1 A/min. The chamber will be vented later today. The pellets and the thermocouples will be inspected.

 Monday, May 13, 2013, 17:21

The following table shows the characteristics of the pellets after sintering at 600 A for 13 hours.

Sample,   Mass (g),   Thickness (mm),   Density (g/cm3),    Diameter (mm)

1    0.8904 4.875 1.364 13.058

2    0.8991 4.744 1.396 13.148

3    0.8846 4.579 1.482 12.884

4    0.9142 4.981 1.254 13.650

5    0.9022 4.978 1.250 13.586

Avg 0.8981 4.831 1.345 13.265

Evaporator #2 is still under construction.  For further information please contact Jens Lassen.

Rick mentioned to me that the evaporator is ready for the next steps of the commissioning process.
In the chamber only the target leg heaters have current by-pass clamps on them. 
The ionizer tube heaters do not have them because these lines do not have the same configuration as the others. The current by-pass clamps will 
not fit these lines.

We may not need this for the commissioning, Rick will design and manufacture something  for this when I get back from holiday.

The water is on in all circuits except for the power supply cooling circuit.

Pierre

 Monday, February 13, 2012, 16:21

The Evaporator 2 is now commissioned.  See attachment#1 for the commissioning report or refer to Document #43321.  

Thursday, March 01, 2012, 14:35

Both the IEVAP2:TBHT and IEVAP2:TGHT maximum current setpoints on the vacuum page (see page: /edl/ievap2_vacuum1.edl) are wrong. 

For IEVAP2:TGHT, the maximum current setpoint should be 1500A (see page: /edl/ievap2tghtcp.edl), not 1000A. 

For IEVAP2:TBHT, the maximum current setpoint should be 500A (see page: /edl/ievap2tbhtcp.edl), not 300A. 

See attachement#1 for grabscreen. 

Fault: 5853

 Tuesday, March 20, 2012, 14:22

The Evaporator #2 backing pump (IEVAP2:BP1) muffler has not connected to the exhaust duct.

 See attachment#1 as to where the muffler should be connected to the exhaust ducting system.  

The Evaporator chamber is currently under vacuum; the BeO sintering process will be pending for now until the backing pump is properly installed. 

(ISAC E-fault 5880) 

 Wednesday, March 21, 2012, 13:55

Edi Dalla Valle is connecting the evaporator backing scroll pump exhaust to the existing nuclear exhaust. (See attachment#2: scroll_pump_exhause.jpg).  A filter is also added between the exhaust line 

to prevent any back flow of oil from the Evaporator #1 backing pump (An oil pump). 

Work is covered under ISAC WP# 2012-03-21-3.

The evaporator is now operational. 

 Tuesday, May 15, 2012, 13:45

It was discovered that one of the insulators that supported the target module broke apart (see Attachment#1).  This might be caused by the heat from the target legs that reflected back from the base to the insulators.  The burnt marks are the evidence.  

A stainless metal sheet is used as the heat shield  (see Attachment #2). 

 Tuesday, May 15, 2012, 17:00

It was found that there were water droplets from the TBHT cooling line.  The joint is leaky.  (see attachment 1) 

A message has sent to Rick M. 

 Tuesday, May 15, 2012, 17:03

The tube heater power supply current readback and setpoint are not matching.  Ray Dube checked the power supply and confirmed that it is faulty.  He will replace a functional p/s tomorrow. 

 Friday, May 18, 2012, 13:24

The original p/s was replaced with a new one and there was still a discrepancy between the readback and the setpoint.  After checking with the drawings for the ITE/ITW tube heaters, it was confirmed that the connections for the Evap#2 tube heater control were wrong.  (see attachment 1).  The connections were corrected and the power supply is now operational. 

John Wong wrote:

Tuesday, May 15, 2012, 17:00 It was found that there were water droplets from the TBHT cooling line.  The joint is leaky.  (see attachment 1)  A message has sent to Rick M.

 Wednesday, May 16, 2012, 14:01

The connector was re-tighten.  The water valve was opened, and no water leaks were found.

Monday, May 28, 2012, 11:08

It was discovered this morning that the Evaporator #2 chiller was leaking water from the bottom (see attachment 1).  A puddle of water was formed and eventually found its way down to the Hotcell. 

The evaporator was running over the weekend for the BeO pellets process.  The TGHT is now off and the chiller will be inspected... 

Tuesday, July 17, 2012, 15:45

Target boat is filled with TaC coated regular- and D-endcaps. 

The boat is wrapped with a Ta heat-shield. 

Chamber is being pumped down, currently at 5e-6 Torr.

Tuesday, July 17, 2012, 15:58

Heat-shield cooling water valve opened; no leaks detected.

Initiated TGHT auto-ramping at 0.5A/min, set TGHT max at 580A.

 Wednesday, July 18, 2012, 10:44

Yesterday evening, the target heater tripped off a few times due to high vacuum excursion.  The TGHT ramping rate was low to 0.2A/min.  The current was ramped up sturdily to 500A this morning.  

Wednesday, July 18, 2012, 10:46

Increased ramping rate to 2A/min.  Vacuum currently at 2.2e-6 Torr.

 Wednesday, July 18, 2012, 16:18

TGHt has reached to 580A and stayed for about 5 hrs. 

Cooling down in process...  2A/min for TGHT --> 0A.

 Thursday, July 19, 2012, 10:31

TGHT reached to 0A. 

Evaporator is off. 

Venting chamber... 

Monday, July 30, 2012, 15:38

The evaporator was used for the processing the NiO target for 8 days and it was discovered today that there was a puddle of water underneath the chiller. 

The cover of the chiller was removed and some water around the plumbing was found (see attachment #1). 

Will continue to keep running the chiller to see if there is more water leaking out...

 Friday, August 10, 2012, 19:54

Target boat with TaC coating, inside covered with a 0.002 inches thick Ta foil, wrapped with a 0.002 inches thick Ta foil, contains a Ta foil with TaO coating.

See John's Ipad for their recipes.

Evaporator #2 is now auto-ramping overnight at 0.2 A/min, up to 830 A, with the maximum voltage limited at 14 V, between 2.00e-05 (Good vacuum) and 3.00e-05 Torr (Bad vacuum).

Nikita Bernier wrote:

Friday, August 10, 2012, 19:54   Target boat with TaC coating, inside covered with a 0.002 inches thick Ta foil, wrapped with a 0.002 inches thick Ta foil, contains a Ta foil with TaO coating. See John's Ipad for their recipes. Evaporator #2 is now auto-ramping overnight at 0.2 A/min, up to 830 A, with the maximum voltage limited at 14 V, between 2.00e-05 (Good vacuum) and 3.00e-05 Torr (Bad vacuum).

 Saturday, August 11, 2012, 19:15

Heating process was going smoothly up to 400 A. See Attachment 1.

Around 420 A, vacuum went up again and the voltage increased more quickly. It seems like resistance is building up. After reaching 530 A, the current was tapped down to 420 A in an effort to save the Ta boat. See Attachment 2.

The current will stay at 420 A for the weekend until John takes a look at this.

Nikita Bernier wrote:

Nikita Bernier wrote:  Friday, August 10, 2012, 19:54   Target boat with TaC coating, inside covered with a 0.002 inches thick Ta foil, wrapped with a 0.002 inches thick Ta foil, contains a Ta foil with TaO coating. See John's Ipad for their recipes. Evaporator #2 is now auto-ramping overnight at 0.2 A/min, up to 830 A, with the maximum voltage limited at 14 V, between 2.00e-05 (Good vacuum) and 3.00e-05 Torr (Bad vacuum).    Saturday, August 11, 2012, 19:15 Heating process was going smoothly up to 400 A. See Attachment 1. Around 420 A, vacuum went up again and the voltage increased more quickly. It seems like resistance is building up. After reaching 530 A, the current was tapped down to 420 A in an effort to save the Ta boat. See Attachment 2. The current will stay at 420 A for the weekend until John takes a look at this.

 Monday, August 13, 2012, 13:46

 TGHT was ramped down at 2 A/min and then tapped down to 0A. See Attachment 1.  The target boat will be cooled down for about an hour before turning off the chiller.

Tuesday, August 14, 2012, 15:01

The Cu-heatshield insulators are broken due to prolong heating time during the target processes (see attachment#1). 

The insulators are replaced with the MM800 type (see attachment #2).

Nikita Bernier wrote:

Nikita Bernier wrote: Nikita Bernier wrote:  Friday, August 10, 2012, 19:54   Target boat with TaC coating, inside covered with a 0.002 inches thick Ta foil, wrapped with a 0.002 inches thick Ta foil, contains a Ta foil with TaO coating. See John's Ipad for their recipes. Evaporator #2 is now auto-ramping overnight at 0.2 A/min, up to 830 A, with the maximum voltage limited at 14 V, between 2.00e-05 (Good vacuum) and 3.00e-05 Torr (Bad vacuum).    Saturday, August 11, 2012, 19:15 Heating process was going smoothly up to 400 A. See Attachment 1. Around 420 A, vacuum went up again and the voltage increased more quickly. It seems like resistance is building up. After reaching 530 A, the current was tapped down to 420 A in an effort to save the Ta boat. See Attachment 2. The current will stay at 420 A for the weekend until John takes a look at this.    Monday, August 13, 2012, 13:46  TGHT was ramped down at 2 A/min and then tapped down to 0A. See Attachment 1.  The target boat will be cooled down for about an hour before turning off the chiller.

 Tuesday, August 14, 2012, 16:56

Summary:

The purpose of this experiment is to test the chemical and high temperature (1600C) resistance of a Ta foil (0.001" thick) coated with Ta2O5, so it can be used as the under-layer for the BeO sintering process.

The Ta2O5 (white powder, -325 mesh) was prepared in a non-aqueous solution and was sprayed on a piece of Ta foil. 

The coated foil was rolled up and inserted in a Ta-coated (previously sintered) target boat for heating.

The foil was heated up to 520A (~1200C) and evidently,Ta2O5 started to react with Ta foil, and the foil became brittle and cracked (see attachment#1).

In conclusion, Ta2O5 is not a good protection layer for Ta material - at least for our applications.