Presentation is loading. Please wait.

Presentation is loading. Please wait.

Spectrometer Solenoid Test Plan Workshop: Spectrometer Solenoid Overview Steve Virostek - LBNL February 17, 2012.

Similar presentations


Presentation on theme: "Spectrometer Solenoid Test Plan Workshop: Spectrometer Solenoid Overview Steve Virostek - LBNL February 17, 2012."— Presentation transcript:

1 Spectrometer Solenoid Test Plan Workshop: Spectrometer Solenoid Overview Steve Virostek - LBNL February 17, 2012

2 LBNL Spectrometer Solenoid Test Plan Workshop - 2/17/2012 - 2 -- 2 - Magnet Overview  Steve Virostek  LBNL Topics Overview of the Spectrometer Solenoids Overview of the Spectrometer Solenoids Key magnet requirements Key magnet requirements Recent magnet operation Recent magnet operation Design modifications Design modifications  Heat reduction to 4.2K  Radiation shield improvements  Cryocooling power  Other improvements

3 LBNL Spectrometer Solenoid Test Plan Workshop - 2/17/2012 - 3 -- 3 - Magnet Overview  Steve Virostek  LBNL MICE Cooling Channel Layout Spectrometer Solenoid #1 Spectrometer Solenoid #2

4 LBNL Spectrometer Solenoid Test Plan Workshop - 2/17/2012 - 4 -- 4 - Magnet Overview  Steve Virostek  LBNL Performance Overview Key magnet requirements: Key magnet requirements:  All five coils must be trained to 275 amps  The cryocoolers must maintain the LHe in the cold mass (no boil-off) Not yet achieved for either magnet

5 LBNL Spectrometer Solenoid Test Plan Workshop - 2/17/2012 - 5 -- 5 - Magnet Overview  Steve Virostek  LBNL Magnet 2B Operation A single-stage cooler had been added to increase cooling at the HTS lead upper ends and to help reduce the shield temperature A single-stage cooler had been added to increase cooling at the HTS lead upper ends and to help reduce the shield temperature Magnet 2B was trained in series to 258 amps when a coil lead was found to contain an open circuit Magnet 2B was trained in series to 258 amps when a coil lead was found to contain an open circuit The failure was traced to the M2 coil close to the He/vacuum feedthru The failure was traced to the M2 coil close to the He/vacuum feedthru Training on the Center, E1 and E2 coils in series continued, reaching 270 amps Training on the Center, E1 and E2 coils in series continued, reaching 270 amps During operation, the 3+1 cooler configuration could not maintain a closed LHe system During operation, the 3+1 cooler configuration could not maintain a closed LHe system

6 LBNL Spectrometer Solenoid Test Plan Workshop - 2/17/2012 - 6 -- 6 - Magnet Overview  Steve Virostek  LBNL Magnet 2B Cross Section

7 LBNL Spectrometer Solenoid Test Plan Workshop - 2/17/2012 - 7 -- 7 - Magnet Overview  Steve Virostek  LBNL Added Single Stage Cooler

8 LBNL Spectrometer Solenoid Test Plan Workshop - 2/17/2012 - 8 -- 8 - Magnet Overview  Steve Virostek  LBNL Magnet 2B Disassembly After warm-up, the cold mass was removed from the vacuum vessel and opened After warm-up, the cold mass was removed from the vacuum vessel and opened The failed lead was located just inside the cold mass feedthrough The failed lead was located just inside the cold mass feedthrough Analysis indicated that the conductor adjacent to the feedthru needed stabilization against movement and for enhanced cooling Analysis indicated that the conductor adjacent to the feedthru needed stabilization against movement and for enhanced cooling The internal quench resistors in Magnet 2B were found to be damaged due to overheating The internal quench resistors in Magnet 2B were found to be damaged due to overheating Magnet 1 resistors were not damaged Magnet 1 resistors were not damaged

9 LBNL Spectrometer Solenoid Test Plan Workshop - 2/17/2012 - 9 -- 9 - Magnet Overview  Steve Virostek  LBNL Subsequent Analyses The heat leaks from dominant static sources were re-evaluated, focusing on heat leaks to 4.2K (LHe boil-off issue) The heat leaks from dominant static sources were re-evaluated, focusing on heat leaks to 4.2K (LHe boil-off issue) Other operational aspects considered: heat loads on the shield and vacuum insulation Other operational aspects considered: heat loads on the shield and vacuum insulation The design of the passive magnet protection system design was also analyzed under various operational regimes The design of the passive magnet protection system design was also analyzed under various operational regimes

10 LBNL Spectrometer Solenoid Test Plan Workshop - 2/17/2012 - 10 - Magnet Overview  Steve Virostek  LBNL Design Modification Approach The design and assembly modification plan was developed based on the following: The design and assembly modification plan was developed based on the following:  reduction of heat leaks to the cold mass  the addition of more cryo cooling power  modification of the cold leads near the feedthroughs to prevent burn-out  thermal heat sinking of the quench resistors Details provided on the following slides Details provided on the following slides

11 LBNL Spectrometer Solenoid Test Plan Workshop - 2/17/2012 - 11 - Magnet Overview  Steve Virostek  LBNL 4.2K Heat Load Reduction Improved vacuum pumping and instrumentation Improved vacuum pumping and instrumentation 4K areas covered with actively cooled shield where possible 4K areas covered with actively cooled shield where possible Baffles added to vent lines to prevent radiation shine to 4.2K Baffles added to vent lines to prevent radiation shine to 4.2K Possible thermal acoustic oscillations in vent/fill lines to be monitored w/pressure gauges Possible thermal acoustic oscillations in vent/fill lines to be monitored w/pressure gauges Improved application of MLI on cold mass Improved application of MLI on cold mass Sensor wires optimized & w/proper heat sinking Sensor wires optimized & w/proper heat sinking

12 LBNL Spectrometer Solenoid Test Plan Workshop - 2/17/2012 - 12 - Magnet Overview  Steve Virostek  LBNL Radiation Shield Improvements Radiation shield remade w/6.35 mm thick 1100 series aluminum (except for the inner bore) – previously 6061 Radiation shield remade w/6.35 mm thick 1100 series aluminum (except for the inner bore) – previously 6061 Improved thermal connection between cooler first stage and radiation shield (copper sheets vs. aluminum tubes) Improved thermal connection between cooler first stage and radiation shield (copper sheets vs. aluminum tubes) Application of MLI on shield improved Application of MLI on shield improved Heat loads decreased as possible: shield pass-through holes for the cold mass supports, intermediate cold mass support heat intercepts, and shielding of the warm end of the supports Heat loads decreased as possible: shield pass-through holes for the cold mass supports, intermediate cold mass support heat intercepts, and shielding of the warm end of the supports

13 LBNL Spectrometer Solenoid Test Plan Workshop - 2/17/2012 - 13 - Magnet Overview  Steve Virostek  LBNL Quench Resistor Heat Sinking

14 LBNL Spectrometer Solenoid Test Plan Workshop - 2/17/2012 - 14 - Magnet Overview  Steve Virostek  LBNL Other Design Modifications Other key improvements: Other key improvements:  Total cooling power increased to five 2-stage pulsed tube coolers and one single-stage cooler  Extra copper/superconductor added near cold mass feedthroughs for increased cold lead stability Other improvements/additions: Other improvements/additions:  LBNL/MICE personnel assisting with magnet reassembly  Detailed MLI inspection carried out during assembly  Fast DAQ system will continuously monitor voltage taps  Additional temperature sensors added to the logging system

15 LBNL Spectrometer Solenoid Test Plan Workshop - 2/17/2012 - 15 - Magnet Overview  Steve Virostek  LBNL 5 + 1 Cryocooler Layout


Download ppt "Spectrometer Solenoid Test Plan Workshop: Spectrometer Solenoid Overview Steve Virostek - LBNL February 17, 2012."

Similar presentations


Ads by Google