Internal review of superconductors and magnet laboratories 2

Internal review of superconductors and magnet laboratories 2 nd part: SM 18 & b. 163: current status, weak points, possible improvement Cryogenics 19 -May-2009 Vladislav Benda (CERN), Klaus Barth (CERN) Review of cryo laboratories

SM 18 operational diagram 19 -May-2009 Review of cryo laboratories 2

SM 18 equipment 1/2 Component Parameters Note Cold box 6 k. W Linde m=25 g/s at P=19. 3 b with LN precooler Possible upgrade: • On line purifier • Turbines to be optimized Compressors of the cold box Stal compressors: 2 compressors from 1 to 5 bar 1 compressor from 5 to 20 bar Flow 100 - 400 g/s Total power 1. 3 MW OK Recovery HP compressors 3 identical 5 stages compressors Burckhardt Flow 3 x 130 m 3/h at 1 bar Power 3 x 40 k. W Pressure 200 b Maintenance/replacement (300 KCHF) is required, as they are old and in bad condition. Compressors are not required if a full flow purifier (20 b) is installed. HP purifier High level of impurities acceptable (5%) Maximum flow 2 x 200 m 3/h Pressure 200 b HP purifier is not needed if the full flow purifier is installed. 1. 9 K Pumping facility 1) WPU 1&CCU 2&H 1 m=18 g/s at 1. 2 k. Pa Qheater=32 k. W at 1 k. Pa If required CCU 3 can be connected to WPU 2. OK 19 -May-2009 2) WPU 2&H 5 m=7. 2 g/s at 1. 2 k. Pa Qheater=32 k. W at 1 k. Pa Review of cryo laboratories 3

SM 18 equipment 2/2 Component Parameters Note Cool down/warm up system CWU 1&2, H 4, H 2, 3 compressors, CWL distrib. line Magnet cooling 120 k. W at 80 K Magnet warming 30 k. W at 320 K GHe return warming 200 k. W at 300 K 3 compressors Kaeser FS 440 Flow of two compressors: 300 g/s at 3 b, P=10 b Third compressor is redundant OK Cryogenic feeder unit CFB 1 pair of 13 k. A CL, 2 pairs of 600 A CLs, HV test in GHe at 300 K&1 b U=3. 1 k. V, GHe/LHe HX 4. 5 g/s, Lambda plate for SC cable from 4. 5 k to 1. 9 K 10 CFBs operational 2 CFBs partially dismantled Cryobox-string LHe at 4. 5 K at 3 b, GHe return, Shield: GHe in at 19 b&50 K, GHe out at 18 b&75 K Cryo lines of CB can be connected either to the cryobox or to Grec. For time being the box is connected to DSL test set up. This set up is foreseen to be adopted for FCM test. RF cavity 2 horizontal, ~5 g/s per bench 4 vertical, big consumption during cool down an filling, small consumption during operation Cryostats are not shielded Distribution line has a very high consumption (~12 g/s). The line is not shielded. A new low heat inleak line including 1. 9 K pumping is required. DSL test set up 1 pair of 600 A CL replaceable for 13 k. A CL, HV test at 2 k. V, Saturated or supercritical He for experiment Originally designed for DSL test 19 -May-2009 Review of cryo laboratories 4

Magnet test facility in SM 18 Heavy cold mass, frequent cool down/warm up, working at 1. 8 K Combined cryogenic line (CCL) GHe Cold compressor unit (CCU) LHe GHe pumping Very low pressure heater (VLPH) Cooling/warming line (CWL) Cooling line Returns Warming line GHe LHe Cryogenic line (CL) 19 -May-2009 Cooling unit (CWU) & GHe heater Review of cryo laboratories Cryogenic feeder units (CFB) 5

GHe/LN pre-cooling system in SM 18 • Is it necessary to pre-cool cold masses with GHe/LN system? It is simpler to cool it down directly with LHe! – Consumption of LHe in litres required to cool down 1 kg of stainless steel • 1 – 32 • 0. 1 – 1. 4 from 300 K to 4 K from 80 K to 4 K – Maximum represent utilization only of a latent heat of LHe – Minimum represent a full enthalpy – Real figures depends on heat exchange during a cool down • It is evident that for heavy cold masses frequently cool down the GHe/LN pre-cooling system is more economic. 19 -May-2009 Review of cryo laboratories 6

Proposal of SM 18 cryogenic upgrade • SRF cavity – LHe distribution line to be changed – Heat leak to be reduced from ~12 g/s to ~2 g/s (shielded line) – 1. 8 K pumping head to be integrated – Total cost estimation ~ 800 k. CHF • • • Control system from ABB & PCview 32 to UNICOS – Duration: 2 years – Budged required: ~250 k. CHF – Resources required: 1 engineer for 2 years – Implementation by steps • Stop for 2 -3 weeks 19 -May-2009 • All other cryogenic lines shall be low consumption, shielded lines. Full flow dryer and full flow precooler/adsorber to be installed – Downtime reduction by avoiding the clogging – The whole system can work permanently at full power (both 1. 9 K pumping units). – Cost estimation ~ 800 k. CHF (French special contribution? ) Upgrade of 6 k. W cold box from refrigerator to liquefier – 4 turbines to be changed/arranged including pipework – Estimated extra LHe production ~ 4 g/s – Cost estimation ~ 500 k. CHF Review of cryo laboratories 7

Proposal of the new cavity cryogenic distribution line in SM 18 • Design and Technical specification to be done • One valve box required per a bench • Particularity of the line – Twin valve protection • Bench branch lines disconnected while the main line is cold – He guard • Protection of sub-atmospheric circuits • Protection of twin valves volume – Each valve box includes: • One heat exchanger • One phase separator • One He guard 19 -May-2009 Review of cryo laboratories 8

Proposal of the new full low purifier in SM 18 Full flow helium dryer Full flow precooler/adsorber unit 19 -May-2009 Review of cryo laboratories 9

Number of Tests in SM 18 up to 2014 19 -May-2009 Review of cryo laboratories 10

Compatibility with 6 k. W (@ 25 g/s) CB LHe production Average consumption needed (in g/s) 2009 2 nd 2010 1 st 2010 2 nd 2011 1 st 2011 2 nd 2012 1 st 2012 2 nd 2013 1 st 2013 2 nd 2014 1 st 2014 2 nd Cavities (with new cavity line 2 g/s)* 4 6 6 6 10 10 11 25 23 0 0 Magnets 12. 5 13 15 15 17 11 10 11 9 12. 5 9. 5 Total 16. 5 19 21 21 27 21 21 36 32 12. 5 9. 5 Total if existing SRF cavity line (+10 g/s)** 26. 5 29 31 31 37 31 31 46 42 12. 5 9. 5 * Estimated consumption of the new line ~2 g/s ** Consumption of the existing line ~12 g/s • • Considering 6 k. W CB current capacity 25 g/s, the requirements cannot be fulfilled at a present condition. Only if the CB is fully upgraded (~30 g/s) and the cavity transfer line is changed the requirement can be fulfilled except for 2013. Peak of consumption possible: boosting by LHe, GHe to atmosphere or adapting the priorities between the tests. New cavity line and CB upgrade is not expected before 2011. 19 -May-2009 Review of cryo laboratories 11

SM 18 summary • Compatibility of LHe required consumption and LHe production – Reduction of LHe consumption • New distribution SRF cavity cryogenic distribution line • All other cryogenic lines, cryostats and valve boxes to be shielded – Increase of cooling capability • 6 k. W cold box upgrade – In any case the consumption requirement in 2013 cannot be fulfilled • Control system to be transferred to Unicos • Typical tests suitable for SM 18 – Heavy cold masses to be pre-cooled by GHe/LN circulation preferable at high pressure – Working temperature 1. 8 K 19 -May-2009 Review of cryo laboratories 12

Building 163 operational diagram 19 -May-2009 Review of cryo laboratories 13

Building 163 equipment 1/2 Component Parameters Note Cold box Linde/Sulzer Cemtec 5 g/s with LN precooling Filter of turbine is clogged. Origin 1980, recuperated 1997 Compressor of the cold box Kaeser FS 440 80 g/s at 13 b, P=250 k. W, U=400 V Cooling water 7 m 3/h The same compressor is in b. 165 and can be used for the cold box in b. 163 (reciprocity). OK Origin 1998 All pumps are identical OK 5 x 1. 8 K pumps 1 x purge pump Leybold Segelec SV 300 1. 8 K Freska pumping unit 2 x primary Alcatel 34014 1 x roots Alcatel RHV 300 19 -May-2009 P=45 k. W 2 x 400 m 3/h 3000 m 3/h Review of cryo laboratories Very old, no maintainance, leaky. Estimated cost of a new one of the same pumping speed is about 120 k. E. Leybold, fully automatic, one primary: SV 600 & one roots 3000 m 3/h. 14

Building 163 equipment 2/2 Component Parameters Note HP recuperation compressor in b. 253 0 -400 m 3/h, P=180 b OK Two other compressors in bad condition. Buffers for pure He 4 x 80 m 3 at 12 b HP buffers: 70 m 3 at 150 b 6 x 80 m 3 at 12 b close to b. 180 (BEBC) Big d. P (12 b) , Larger diameter of a connecting pipe is required. Buffers for impure He 18 m 3 at 150 b Dryer and purifier, twin 2 x 200 m 3/h P=180 b OK Dryer for impure He 400 m 3/h OK Gasholder 40 m 3 OK 19 -May-2009 Review of cryo laboratories 15

Liquefaction capacity in b. 163 • Nominal capacity • Real capacity • Today capacity 150 l/h 130 l/h ~5 g/s 80 l/h – because of turbine filter clogging (charcoal powder? ) • Change of the filter is foreseen for week 28 – Stop for 3 weeks, Unicos transfer in the same time • Cost estimation 10 k. CHF • Required capacity 130 l/h • Possibility to boost capacity by external source of LHe – Limitation: volume of He buffers • Possibility to use BEBC buffers more efficiently. New connecting line of a larger diameter is required. • At a peak consumption GHe possibly to atmosphere 19 -May-2009 Review of cryo laboratories 16

Building 163 summary • Major part of the equipment is in a good condition • Weak point to be treated – 1. 8 K Freska pumping unit is too old • Its replacement is recommended – Cold box • Clogging of the filter to be investigated and solved – If more often replacement of the filter is required an access shall be improved. • Quite old – Possibility to change it for Block 4 cold box – 6 “BEBC” buffers to be use more efficiently 19 -May-2009 Review of cryo laboratories 17

HP recovery Burckhardt compressors in SM 18 19 -May-2009 Review of cryo laboratories 18

1. 8 K Fresca pumping unit 19 -May-2009 Review of cryo laboratories 19