1. Ageing workshop - N.Tuning
NIKHEF update Ageing workshop 10 Nov 2006 Gras van Apeldoorn & Niels Tuning
3 lines of attack:
HV training (Mod 3)
Damage reappears after 200 hrs
Q: 200hrs of irradiation, or time constant?
Flushing (Mod 2)
Improvement with flushing
Exceptions: worse after opening?
Heating (Mod 30)
No mechanical consequence for module
Cannot confirm beneficial ageing results from Heidelberg
10 Nov 2006
Ageing workshop - N.Tuning

2. Ageing workshop - N.Tuning
1) HV training
Gas flow
Conditions:
Flow: Ar/CO2 70/30, 20 l/hr
Irradiation: 2mCu, 90Sr source
Sequence:
HV training ~40 hrs 1870 and 1920V
Irradiate 340 hrs
HV training 18 hrs 1910 V
Conclusions:
A second HV training helps again
340 hrs
Lower?
After HV
Rel.gain
1st HV training
hrs
2nd HV training
3rd HV training
Lower??
After HV
NB: 700 hrs ~ s
~ 3 months nominal LHC
10 Nov 2006
Ageing workshop - N.Tuning

3. Ageing workshop - N.Tuning
1) HV training
Question:
Does it prevent ageing during 200 hrs of irradiation
Or does it prevent ageing for 200 hrs of flushing…
It looks like 1)
But untrained part improves!?
8 days of flushing
3 days of flushing
29Sep
-3Oct
3Oct
10Oct
1st HV training
2nd HV training
3rd HV training ??
Gain indeed went up
Ratio 10Oct/3 Oct:
10 Nov 2006
Ageing workshop - N.Tuning

4. Ageing workshop - N.Tuning
1) HV training
20hrs
Question:
Is ageing also prevented at previously unirradiated spots (pos. 190cm) ?
Marginally…
This seems in contradiction with measurements of Aug 20 on unirradiated spot (pos. 200cm)
96hrs
Deepest point
Integrated loss over surface
10 Nov 2006
Ageing workshop - N.Tuning

5. 1) Conclusion HV training
Is ageing also prevented at previously unirradiated spots ?
Marginally…
This seems in contradiction with measurements of Aug 20 on unirradiated spot
To be investigated further
10 Nov 2006
Ageing workshop - N.Tuning

6. Ageing workshop - N.Tuning
2) Long term flushing
What happened with module 2 ?
Briefly opened when moved from setup to setup
Gas had finished before worsening of module 2
Flushing is only temporary benificial ?
Compare to result from Heidelberg:
???
Module 63
36.2 m3
100 days
10 Nov 2006
Ageing workshop - N.Tuning

7. 2) Long term flushing: dips in Module 3?
Date
Loc
I(nA)
Time (hrs) 1 3B
18Jan
cleanroom
190 15 2
23Feb
Lab
150 3
21Mar
21.5 4
12Apr 5 3A
15Apr
180 23 6
23May
140 22 7
19Jun 16 8
15Aug 20
20Jun: opened module
during 24days
6Jun: flushed with
4% O2 for 13days
History:
21Mar – 12Apr:
28Mar-11Apr: opened module
15Apr – 23May:
25Apr-10May: played with water bottle
10May-15May: module not connected
23May – 19Jun:
6Jun: Change Ar bottle
6Jun – 19 Jun: Addition of O2
19Jun - 15Aug
20Jun-14Jul: module not connected
10May: opened module
during 5days
28Mar: opened module
during 14days
Bottom line:
We don’t understand long term flushing behaviour…
10 Nov 2006
Ageing workshop - N.Tuning

8. Ageing workshop - N.Tuning
3) Heating Mod 30 Setup
10 Nov 2006
Ageing workshop - N.Tuning

9. 3) Heating Mod 30 Temperature: 1st heating 3 days
Procedure
Module 30 is heated while flushing with CO2
3 heatings:
1 day 35 oC, 3 days 48 oC
4 days 48 oC
13 days 41 oC
Sep29
Oct 2
10 Nov 2006
Ageing workshop - N.Tuning

10. 3) Heating Mod 30 Temperature: 2nd heating 4 days
Oct 5
Procedure
Module 30 is heated while flushing with CO2
3 heatings:
1 day 35 oC, 3 days 48 oC
4 days 48 oC
13 days 41 oC
Oct 6
10 Nov 2006
Ageing workshop - N.Tuning

11. 3) Heating Mod 30 Temperature: 3rd heating 13 days
Oct 17
Procedure
Module 30 is heated while flushing with CO2
3 heatings:
1 day 35 oC, 3 days 48 oC
4 days 48 oC
13 days 41 oC
Constantly at 41 oC
Try to mimic HD procedure exactly:
13 days 41 oC
4 days flushing
Oct 30
10 Nov 2006
Ageing workshop - N.Tuning

12. 3) Heating Mod 30: Geometry
Flatness:
Module is flat to +/- 200 μm
Change after heating <100 μm OK
Width:
Module shrinked by 100 μm +/- 50 μm OK
Shape:
Straight within +/-100μm OK
Gas tightness:
OK, Unchanged: l/s ± l/s
Corresponding to 0.007mb/min OK
10 Nov 2006
Ageing workshop - N.Tuning

13. 3) Heating Mod 30 Geometry: Length
Date a b
Average (a+b)/2
Nominal: 2.46mm
Delta
(mm)
Shrinkage
22Sep
3.69
2.88
3.28
+0.82
25Sep
3.55
3.21
3.38
+0.92
3 Oct
2.74
2.03
2.38
-0.08
1.03
5 Oct
2.27
2.16
2.21
-0.25
10 Oct
2.30
1.55
1.92
-0.54
1.20
17 Oct
2.96
1.74
2.35
-0.11
6 Nov
2.62
2.02
2.32
-0.14
1.01
12.92mm a b
module
table
8.0mm
a+b/2
Length:
Module shrinked by 1.03±0.10mm
Module shrinked by additional 0.2±0.1mm
These shifts are easily seen by eye… OK
10 Nov 2006
Ageing workshop - N.Tuning

14. 3) Heating Mod 30: high currents?
After heating: many channels with high current
Loose wire tension? (shorter module?)
Loose wire tension? (loose soldering?)
Deformation of straw?
Humidity in module?
Broken feedthrough board?
After additional 3 days of flushing: high currents disappeared OK
Scan after heating Oct 16: and additional 3 days of flushing: OK
Scan after heating Oct 12:
10 Nov 2006
Ageing workshop - N.Tuning

15. Ageing workshop - N.Tuning
3) Heating Mod 30 Ageing
Not OK
Ageing:
No sign of improvement after various heatings
Sep 4, after 6 days of flushing
Oct 16, 7days heating +4days flushing
Oct 4, after 3 days at 48 C
Nov 3, 13days heating+4days flushing
Oct 11, after 3+4 days at 48 C
10 Nov 2006
Ageing workshop - N.Tuning

16. 3) Ageing after Heating+Flushing
No sign of improvement after various heatings
Even worse, when compared to unheated modules…
Heating 3:
13 days heating
+4 days flushing
No heating
4 days flushing
Heating 1:
3 days heating
Heating 2:
4 days heating
10 Nov 2006
Ageing workshop - N.Tuning

17. Ageing workshop - N.Tuning
3) Conclusions Heating
Geometry: OK
Shorter due to evaporation of water from panels?
Gas tightness: OK
HV behaviour: OK
Although initially high currents
Ageing: No sign of improvement
10 Nov 2006
Ageing workshop - N.Tuning

18. 3) Heating: Compare to HD
Heidelberg: Irradiation ~90 hrs 55Fe
Mod 20 and Mod 7 heated
Mod 7: Double irradiation (186hr)
NIKHEF: Irradiation ~20 hrs 90Sr
Mod 20+7 have steeper slope?
Mod 20
Mod 7
10 Nov 2006
Ageing workshop - N.Tuning

19. Ageing workshop - N.Tuning
3.2m Module: an oldy…
LHCb
What is the 3.2m module?
Construction date: 2001
Used in 2001 testbeam for TDR
Straws glued to panels with Araldite or Stycast ?
16 channels connected
Wire locator
16 channels
connected
160 cm straws
10 Nov 2006
Ageing workshop - N.Tuning

20. Ageing workshop - N.Tuning
Irradiating 3.2m Mod
Two irradiations, 2 mCu
44 hrs
164 hrs
 smaller damage
23 hrs
Gas flow
20 hrs
118 hrs
20+22 hrs
164 hrs
10 Nov 2006
Ageing workshop - N.Tuning

21. Ageing workshop - N.Tuning
Irradiation 3.2m Mod
3.2 m module (2001):
 very little damage
3.2m: 15% after 200hrs
Mod3: 35% after 200hrs
Smaller damage due to
Stycast?
Age?
Compare to F-mod 3:
10 Nov 2006
Ageing workshop - N.Tuning

22. Ageing workshop - N.Tuning
Conclusions + outlook
Cannot reproduce beneficial effect of heating
Don’t understand (non) beneficial effect of flushing
Need to investigate HV training further
Next, investigate openable module (WARSAW) and find ageing component by adding components one-by-one
10 Nov 2006
Ageing workshop - N.Tuning