Cryogenic Improvements for the ATLAS Energy Upgrade Cryogenic Operations Workshop May 9-11, 2006 Presented by Steve MacDonald Argonne National Laboratory A Laboratory Operated by The University of Chicago
Presentation Overview ATLAS Overview Cryogenic System Staged Construction Energy Upgrade Refrigerator Installation Project Expected Benefits Questions
ATLAS Facility Overview Argonne Tandem Linear Accelerating System (ATLAS) World s First Superconducting Ion Accelerator Located at Argonne National Laboratory National user facility funded by DOE ~6000 hrs/yr beam on target
Split Ring Type Superconducting RF Cavities 47 Total 12 Cryostats - 7 Accelerating, 6 cavities each - 5 Bunchers, 1 cavity each
Original LHe Flow Schematic Model 1400 installed 1978 1400 replaced by 1630 in 1980 Series arrangement Staged construction Cryostat heat exchangers Supply line undersized Supply pressure set by refrigerator/booster secondary Return pressure maintained by dewar heater
ATLAS Section Dedicated 1985 Added 300 watt CTI model 2800 Increased supply line size Need for cross-connect Higher pressure in Booster Dewar level control - Requires ~30 watts excess - Susceptible to load changes
Positive Ion Injector (PII) Cryostats and Cavities 1992 3 Cryostats 6 Cavities Each Gravity fed
Current ATLAS LHe Flow Schematic ATLAS LHe SYSTEM PHASE SEPARATOR 4T 3T 2800W BOX MM 1630 6T 5T 2T 2800E 1MM 3MM 2MM 1WE1 3WE1 2WE1 BOX T 1T 4TT 2TT 5TT 3TT 1TT BOX TT 1L HX L HX J 1J 1K HX K WE 2 L DEWAR (1000L) WE 1 J DEWAR (1000L) K DEWAR (1000L) WE 3 N.O. VALVE TEST CRYOSTAT BOX Z N.C. VALVE 2Z THROTTLE VALVE 3Z BOX R CONTROLLED VALVE 1Z BOX P BOX N 6M 7M 4M 2M BOX A BOX B HX B BOX C HX C BOX D 4D HX C 1R 2R 2S 4U BOX U BOX V BOX E HX E BOX F HX F BOX G BOX W BOX X 5M 6A 3U 6G 4A 4G 1M 3S 6P 3P 6N 3N 3M 5A 3A 3B 3C 3D 1S 3V 6V 3E 3F 3G 5G 3W 6W 3X 5P 4P 2P 1P 4N 5N 2N 1N BOX M 2A 1A 2B 1B 2C 1C 2D 1D 2U 1U 1V 2V 4V 5V 1E 2E 1F 2F 1G 2G 1W 2W 4W 5W 1X 2X BOX S P O N B1 A B C D B2 B3 E F G B4 M5 B5 PII LINAC CRYOSTATS BOOSTER LINAC CRYOSTATS ATLAS LINAC CRYOSTATS J.R.Specht 1/15/96 REV 1: 09/03/03 File # ATALSHE2.VC6
ATLAS Energy Upgrade - ~25-40% Increase in beam intensity - Replace the last cryostat in ATLAS - Install 300 watt CTI model 2800 New ATLAS Cryostat
2800 Installation Critical tasks - Helium line design and fabrication - Refrigerator testing - Installation
2800 Center Test Last operated in late 90 s Test the repair of shipment damage/modification 80 K trap differential pressure Control system operation Capacity check Equipment - Existing spare compressors - RDT Transfer line - 250 Liter portable dewar w/heater
2800 Damage
2800 West Flow Schematic
Installation Schedule Summary - 1 Week shut down - 3 Week installation -1 Week startup
Benefits Provide capacity for new cryostat Add stability and decrease operating costs - Increase operating margin ~10% - Abandon dewar level control - Half of the cryo group call-ins - 1630 is highest maintenance item - ~20% of cryogenic budget/yr - Shut down every 4-6 months as opposed to 18 months Easier to shutdown 2800 East Run 2-3 cryostats with 2800 East down Vacuum break
Presentation Summary ATLAS Overview Cryogenic System Staged Construction Energy Upgrade Refrigerator Installation Project Expected Benefits