LHC Performance Workshop (Chamonix 2016 )

LHC Performance Workshop (Chamonix 2016) Sessions 3 : LHC Hardware Performance Cryogenics G. FERLIN on behalf of TE-CRG group With contribution from K. Brodzinski, S. Claudet, D. Delikaris, L. Delprat, E. Rogez and L. Tavian

Hardware status and Availability 2015 Performance aspect 2016 Expected Hardware performance 2016 Improvement foreseen all along the year Cryogenic power studies BS thermal load IT movement investigation Agenda TE-CRG-OA

Run2 configuration • Two 4.5 K cold boxes + one cold pumping unit except P18/P2 w.r.t scenario for Run 1 (1 Cryoplant /2 sectors) Pro • Additional installed capacity for BS scrubbing • Better availability expected (less rotating component running). • One parallel quench/sector could be recovered without delay • Lower energy consumption (-2 MW) as collateral bonus Cons • In case of multiple quenches in parallel (more than 3 cells !!!) , the recovery time should be affected. (never occurs during 2015) • In case of 1.9 K trip, two sectors will be lost. (never occurs, as mostly seen in S12/S23 not concerned by this configuration) • Tuning of this new configuration at P18/P2 not yet possible. • More than 3 parallel quenches will increase the recovery delay Hardware configuration 2015 TE-CRG-OA

Overall Availability 2015 [Cryo Maintain] Statistic for run 2 from April 5th to Dec 14, TS excluded Supply failures mainly during spring (Post LS1 effect Users failures mostly due to quenches @ 6.5 TeV Downtime in line with Run 1 despite higher beam induced heat loads TE-CRG-OA

Overall Availability 2015 [Cryo Maintain] Statistics in line with our Cryo monitoring Downtimeis to beconsidered as average for eachcategory. PLCs: averagedowntime = 18h12min /// frequency = 1 every 2 months Cold Compressors: averagedowntime = 6h34min /// frequency = 1 every 3,5 weeks OP / Human Factor: averagedowntime = 4h32min /// frequency = 1 per month Elec / Instrum / Tunnel: averagedowntime = 1h45min /// frequency = 1 every 10 days DFBMI: averagedowntime = 0h4min /// frequency = 1 every 2 days DFBAF: averagedowntime = 0h3min /// frequency = 1 every 4 days 4 contributors for 75% of total cryodowntime Most frequentcontributors OP factor: Mostly new OP staff (<30% experienced with Run 1) and no more capacity margin TE-CRG-OA

Overall Availability 2015 [Cryo Maintain] Downtime per categories and mitigation action undertaken Most frequent CM losses: - DFBMI: 39 losses; Should be solved during YETS- DFBAF: 29 losses; Trigger origin should be discussed with stakeholders (thresholds, timer…) Most time-consuming CM losses: - 1.8 K units: 8 losses, Average equivalent to Run 1; should devrease if new configuration P18/P2 works well. - PLCs: 4 losses, should be solved with new firmware during YETS- OP/Human factor: 9 losses; should be partially solved by process optimization under high BS load - Elec/Instrum/Tunnel: 22 losses; Average equivalent to Run 1 TE-CRG-OA

2015 Hardware reliability for Cryoplants Hardware reliability 2015 0.7 0.8 0.3 0.8 Failure rate / unit / year 2 1.5 1.8 1.6 TE-CRG-OA

Hardware fault breakdown In line with 2012 good data + “Supply” in spring and Cryo PLC’s (Treated in TS or YETS) Multiple origins, less straight forward to improve Hardware reliability 2015 Hardware fault in line with Run 1 TE-CRG-OA

Hardware status 2015 Refrigeration Main hardware issue solved during YETS warm compressor degradation diagnosed preventively and replacement without damage nor impact Major leak on 18 kW plant 3 turbines failure, No impact, compensated by Liquid Nitrogen TE-CRG-OA

Hardware status 2015 Refrigeration: YETS improvement • Distributed failures • 16 valves for turbine Control • 4 Cryo PLCs • Activated charcoal replacement (P6/P4/P8); • Risk identified with some oil removal systems, worth the effort and follow-up • Software update all around LHC • Partial Cold Compressor VFD & AMB exchange • 24 VDC consolidation • ……. TE-CRG-OA

Performance aspects TE-CRG-OA

Expected Hardware performance 2016 cleaning s12, 23, 81, 78 W/hc p+/bunch cleaning s34, 45, 56, 67 installed capacity + margin form 1.9K unit at lower flow than designed Theoritical LHC nominal heatloads In 2016 we will be able to provide at least the same capacity as in 2015 after 8b4e bunch train test 85 limit S23 installed capacity limit for 4.5-20K 36 bunch trains 72 bunch trains 72g72 bunch trains 144 bunch trains TE-CRG-OA bunch number K.Brodzinski_6th Evian_2015.12.15

Expected Hardware performance 2016 Main improvement foreseen all along the year Software improvements to fulfill the cryogenic power increase (continued effort as in 2015 Automatic adaptation to follow the thermal load on BS (must be tuned online!) Tuning of installation to prepare a scheme for high load Anticipation of the thermal load before beam Smooth Decrease of the thermal load by electrical heating after dump For FDBAF, a new settings of the threshold (absolute value and timer) should decrease drastically the quantity of losses of the Cryo Maintain signal. … “Data mining” to anticipate possible issues on tunnel components (1st studies started last year with former EN-ICE); On & Off line tracking of process deviations and abnormal behavior. TE-CRG-OA

Expected Hardware performance 2016 • Hardware configuration This configuration will be tested before the end of YETS 2015 The aim is to decrease the number of rotation machine to improve the global availability The second target is to boost the cooling power of the Cryoplant in P2 and consequently the BS cooling power for the S23(cooling capacity margin to be evaluated during tests, to be used in addition to previously defined actions for S23) Specific configuration with non symmetry TE-CRG-OA

Cryogenic power studies BS thermal load (Maximum plant power validation) Due to a limited margin for sector S23 the proposition consists to define a road map to increase the margin and to reach the ultimate power; A first step consists to perform a power survey of the Cryoplant unit not connected to sector in P2 (same power survey for the twin plant in P8). (already foreseen during the restart of the plants). The second step consists to Perform a maximum BS load on the sector by using electrical heater installed on BS circuits. In parallel, perform the same test on the twin plant installed in P8 This second step is not included in the YETS time schedule and should be included if confirmed (3 to 4 days) TE-CRG-OA

Cryogenic power studies BS thermal load (Process upgrade to reach higher power) This operation scheme was not foreseen originally. Hardware modification are necessary to be able to use this configuration with higher effects on all points. A prototype should be installed during EYETS and after validation the 3 others installation should be updated during TS2 Cryogenic power recovery by using cold bypasses and associated issue / propositions Theoretical interest: Recover cooling power for BS cooling A new test is foreseen at P2 (see slide above) Practical limitations of this scheme do not shows a high margin on measured sectors TE-CRG-OA

Cryogenic power studies He storage Compression Compression Refrigerator (liquefier) Refrigerator (economizer) A B 1.9 K circuit 1.9 K circuit 4.5 K circuit 4.5 K circuit Magnets supply Magnets supply TE-CRG-OA

Cryogenic power studies ITR8 movement investigation In order to investigate the ITR8 oscilation, a step by step check sequence is proposed to identify concerned circuit if any This sequence should be: Adjust Pressure difference with DFBX to stop refilling Block all valves Validation the oscillations during a significativeperiod. This sequence is not yet planned and needs 2 to 3 days to be done (possibly during powering test of the sector?) TE-CRG-OA

Summary • Beam Screen heat load mitigation • Installed power ~110 W/h-cel, 160 W/h-cel already reached except S23 with plan to understand the lower margin • Software optimization on going to fit with 2800 bunches • Data mining to detect online smooth drift and anticipate possible issues. • Proposition to test an upgraded cold by-pass, during EYETS, for recovering additional margin. TE-CRG-OA For 2016, Cryo team expect a global availability in the range 93 to 95 %with CRG origin fault below 5%

LHC Performance Workshop (Chamonix 2016 )