1.
Status of HRMT23 Activities F. Carra, E. Berthomé, G. Gobbi HL-LHC Collimators: Design, Engineering and Prototyping Meeting 1 December, 2016

2. Opening of the Test Bench
HRMT23 was stored in b. 954, sealed
RP measurements at contact with the test bench showed acceptable values (dose rate 80 mSv/h at contact with the downstream flange)
However, impossible to exclude a priori a contamination risk  agreement with A. Hervé, K. Weiss to perform the opening at b. 867-R-P58 (EN/STI bunker, with closable roof). Space created pushing aside HRMT28 test bench
Light procedure decided (limited availability time of the room, uncertainty on the state of the conditions inside the tank):
Opening of the upper plate
RP measurements (dose rate at contact with the jaws and contamination)
If everything ok, extraction of the three jaws with a crane
Dismounting of RF fingers and packaging of the jaws
Closing of the tank
Estimated duration: 4h30m (conservative), target: keep the collective dose below 100 mSv
Federico Carra – EN-MME

3. Federico Carra – EN-MME
Transport to b. 867-R-P58
Done on Tuesday 8th November
Federico Carra – EN-MME

4. Federico Carra – EN-MME
Tank Opening
It took ~3h (13h30 – 16h30)
Performed by S. Favre (EN-MME-MA) with support from E. Berthomé. K. Weiss and C. Saury from RP
No contamination found. Maximum dose at contact with the jaws, 80 mSv/h. Collective dose for the intervention: ~10 mSv
Federico Carra – EN-MME

5. Federico Carra – EN-MME
Jaws Extraction
TCSP
Jaw CFC undamaged (some beam trace on the surface, but no external sign of failure)
Downstream Glidcop tapering locally melted, with oxidation of the BPM button (sign of high temperature reached)
Federico Carra – EN-MME

6. Federico Carra – EN-MME
Jaws Extraction
TCSPM MoGr
A scratch provoked by the beam, surface phenomenon ( micron depth?). No sign of failure of MoGr.
Both MoGr taperings ok, no trace of high temperature on the BPM buttons
Federico Carra – EN-MME

7. Federico Carra – EN-MME
Jaws Extraction
TCSPM CuCD
Grooves generated by the higher-intensity beam impacts
Local fracture of the bulk material at the block/block contacts
Damage can be recovered through the 5th axis
Both MoGr taperings ok, no trace of high temperature on the BPM buttons
Federico Carra – EN-MME

8. Federico Carra – EN-MME
Jaws Packaging
Jaws inserted into plastic bags and CR code applied on all, then registered in TREC
Then placed on a pallet, also registered in TREC as the container of the three items (HCPWPAB001-CR000002)
Tank closed, everything re-transported to b. 954
Federico Carra – EN-MME

9. Metrology and Electrical Conductivity Measurements
Pallet with the three jaws transported to the EN/MME metrology on Tuesday 29th November
Temporary radiation-controlled area prepared around the machine
1st Goal: perform the same measurement of flatness done before the test, to look for plastic deformation of the Glidcop support and of the blocks, block/clamp sliding, etc.
Pre-test metrology on EDMS:
2nd Goal: map the electrical conductivity of the CFC, MoGr and CuCD, to look for a possible degradation provoked by the test (Sigmatest)
Federico Carra – EN-MME

10. Metrology Measurements
Analysis of results ongoing
Federico Carra – EN-MME

11. Metrology and Electrical Conductivity Measurements
Sigmatest measurements on the beam-side surface.
Irradiated jaws measured only in the vertical centre of each jaw. Comprehensive mapping after disassembling.
Pristine
Irradiated
Jaw
Number of measured points (Frequency)
Average value
[MS/m]
Deviation
Average value [MS/m]
Change
CFC
>10 (60kHz)
0.27
0.01
10 (60kHz)
0.31
0.03
+14%
MoGr
72 (960kHz)
0.69 (0.692)
0.05
24 (960kHz)
0.69 (0.686)
-0.9%
CuCD
90 (960kHz)
53.7
9.1
30 (960kHz)
52.4
10.9
-2.4%
Highest frequency was used in CuCD in order to measure only the external cladding. In MoGr the values were similar in all frequencies
Federico Carra – EN-MME

12. Next Steps G. Gobbi managing the test and activity program
Testing of the three jaws
Non-destructive tests before disassembling the jaws
Metrology
Electrical conductivity
BPM performance: are they still operative?
Cooling circuit pressure test? Before or after disassembling?
… ?
Disassembling of the jaws (at the metrology?)
Non-destructive tests of jaw components (blocks, Glidcop housing, pipes, tapering, etc.). For example, measurement of the groove depth (profilometry?), mapping of electrical conductivity, etc. Target: avoid frequent transports from b. 954 to the testing facilities: maximize the number of tests per activity
At a later stage, destructive tests
Recovering of instrumentation, table, preparation of RP wastes
It may involve machining (for example of the table, for HRMT36 use)
Idea is to do it at b. 109, in 2017
Dismounting, machining, sorting of RP wastes: it may be long. Room to be booked for at least 1 week, preferably 2 weeks. To discuss with J. Tonoli, the calendar is very dense
G. Gobbi managing the test and activity program
Federico Carra – EN-MME

13. Federico Carra – EN-MME
Conclusions
At this stage, after HRMT23 opening, no change to the preliminary conclusions given at the LMC in August 2015 (failure of Glidcop tapering, survival of MoGr tapering, survival of MoGr and CuCD absorbers to the respective failure scenarios)
Lots of test to come to evaluate:
BPM survival
Glidcop housing plastic deformation
Cooling circuit under water pressure
Thermo-physical property change of the impact materials
Many thanks to the colleagues involved in these operations! (EN/MME, EN/STI, EN/HE, HSE/RP, SMB/SC, EN/EA, BE/ABP, …)
Federico Carra – EN-MME