02/07/2017 Coordination Meeting
Attendance
This is a periodic meeting the Cryogenics Group has with various representatives on site to discuss future plans or issues related to supporting cryogenic loads at the accelerator, Halls, and the Testlab.
Attendance
Creel, Wright, Schleeper, Fair, Kashy, Bridza, Fansler, Gomez, Oren, Butler, Wood
Agenda and Notes
The purpose of this particular meeting is to discuss the loads on the ESR due to Halls A, B, and C to determine the users plans and identify opportunities to reduce the load on the ESR plant which is operating above its capacity and requiring the support of the CHL/ESR transferline.
1. ESR History
Plant originally built in 1978 for the LBL ESCAR Project. It operated < 900 hours before being shutdown.
Plant was moved to JLAB and installed in 1994 JLAB to support Hall's A, B, and C. The plant has been in nearly continuous operation for more than 22 years.
2. ESR Capacity and costs
Plant capacity envelope is (1500W at 4.5K) OR (800W at 4.5K PLUS 1200W at 15K)
General rules: ESR loses 1 Watt of 4.5K Refrigeration for every 3 watts of 20K refrigeration used and it loses 150 watts of 4.5K refrigeration for every 1g/s of liquefaction used.
Additional TRANSIENT capacity available from CHL via transferline of up to 10g/s at 4.5K depending on the accelerator loads and the flow through the 2K cold box. As the 2K flow increases the liquefaction capability decreases. Using the transferline at 10g/s also increases the cost for power and LN2 at the CHL.
3. ESR2 Upgrade
The Cryogenics group has been pushing the installation of the ESR2 4KW at 4.5K SSC plant for many years. The building was constructed and the cold box placed inside but the real work of designing, installing, and commissioning has slipped several times. This is a multi-year effort to complete this work and requires commitment and funding.
4. Current Issues
At this time the ESR is operating above its full capacity. The CHL1 is supplying approximately 10g/s to ESR at this time via the transferline. If the transferline is shutdown the ESR Dewar level falls. Cryo's worry is operating the ESR at full discharge pressure places more wear and tear on the equipment and pushs weak components toward failure reducing reliability. Limited capacity also increases the recovery time to get all the Halls back online following problems. Continuously relying on the CHL/ESR tranferline also links operations risks of both plants together. This meeting was to discuss options and arrive at an agreed plan or an acknowledgement of the increased risks.
5. Plan Forward
Hall B has submitted the KPP data to DOE for approval. Approval should come in a few days and then we could park the Torus at 80K. Kashy's apprehension is he reported the Torus is operating differently after the last 80K warmup. He reports the JT is no longer flowing enough coolant to provide liquid to the magnet on its own and acts like there is a partial ice plug in the line. They are using the cooldown line to supliment flow to maintain liquid level. If this is the case it will require likely a torus warm up at some point to clear the ice. This issue might indicate the torus needs a 300K warm up to clear a possible plug.
Hall A warm return is routed to ESR. Hall B warm return is routed to CHL. Hall C warm return is routed to CHL.
Paul Brindza indicated the HMS might be able to park at 80K for the summer. Brindza also indicates that Hall C is having a serious pressure drop issues on the cold return for the SHMS system. The rest of the Hall returns and the HMS are not effected. Possibilities are there is a partial plug in the SHMS return line.
Kashy suggested the idea of having the Halls ramp up the lead flows to full and performing a load test to determine the peak load on ESR because the lab is working a physics plan to live near this point in the future.
Action Items
1. Get support to restart the ESR2 4KW plant design, fabrication, and commissioning.
2. Kashy will provide lead flow values to Schleeper to improve the load estimates.
3. Cryo will revisit the capacity matrix predictor and bounce it against the wants of the Hall's.
4. Kashy recommended a test before the end of the run to see where the actual loads are with respect to ESR/CHL capability. This could happen as early as next week.
5. Brindza is requesting help investigating the high SHMS cold return back pressure issue.
6. Cryo is contemplating a request for ESR shutdown and warm up to 300K summer of 18' to perform maintenance if funding supports it.
Action Items Updates and Other Information
1. Ruben states for Hall B solenoid the lead flows are 35.4 SLM (0.10g/s) and 41.3 SLM at full field (0.12g/s)
2. Hall A,B,C Load Discussion Meeting Minutes Apr 30, 2015 Media:Hall_Loads_Meeting_04302015.pdf
3. Directors Review of Cryogenic Capacity 2010 Media:DirectorsReviewCryogenics.pdf
4. Brindza Review of Cryogenic Load on ESR During 12GeV Era Media:Brindza_ESR_12GeV.pdf
5. 12 GeV Nominal End Station Cryogenic Loads from sscmr Media:sscmr.ppt
6. CLAS 12 SC Mag Rev 9_21_06 Kashy Media:CLAS12SCMag.ppt
7. schedule_20151021 Media:schedule_20151021.pdf
8. 20161027.0_LoadVision Media:20161027.0_LoadVision.pdf
9. 20150430.1_LoadVision Media:20150430.1_LoadVision.pdf
