1. LERF Readiness Review Ed Daly / Matt Marchlik
Pressure System, Cryo Processes
November , 2018

2. Outline Section 1: Pressure System Section 2: Cryo Process Outline
Introduction
Analysis
Summary
Section 2: Cryo Process
Processes
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3. Pressure Systems - Outline
Introduction
Analysis
Leak Testing
Summary
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4. Pressure Systems - Introduction
JLAB established the ES&H Chapter Pressure and Vacuum Systems Safety Supplement (PVSSS) to comply with the requirements of 10 CFR 851 “Worker Safety and Health Program”
All JLAB pressure systems constructed on or after January 4, 2016 shall meet the requirements of the PVSSS
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5. Pressure Systems - Introduction
Pressure System # PS-SRF
PS Folder located in DocuShare
Calculations
PS-1 Form (Cover Sheet)
PS-3 Form (Technical Review)
PS-6 Form (Final Mechanical Examination)
PS-7 Form (Leak Test record)
PS-8 Form (Final Walkthrough)
PS-9 Form (System Turnover → Kevin Jordan, System Owner)
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6. Pressure Systems - Introduction
All PS folders will be populated with the required documentation before energizing/commissioning the system
Calculations
WPSs & WPQs
Material certs
Inspection/examination reports
Leak tests reports
PS Forms
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7. Pressure Systems - Introduction
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8. Pressure Systems - Introduction
P&ID JL
In approval process
Nomenclature:
CEVCM03_12 is within zone 03.
CM 2
CM 1
Zone 00
Zone 03
Zone 02
Zone 01
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9. Pressure Systems - Analysis
ASME B Process Piping is the code of record for this system
Analysis number PS-SRF A1
Reviewed/Approved
Located in the Document Repository
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10. Pressure Systems - Analysis
System parameters
Normal Fluid Service
Design Pressures
4 K Supply: 165 psig
Shield Supply: 165 psig
Shield Return: 165 psig
2 k Return: 58 psig
300 K Supply: 150 psig
Cooldown Circuit: 58 psig
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11. Pressure Systems – Leak Testing
Leak testing performed per ASME B31.3 requirements. Positive pressure helium sensitive leak test
The Cryo can’s process piping lines and vacuum boundary have been leak tested at the manufacturer
Transfer line segments (2 ea) have been leak tested at the manufacturer
LCLS-II CMs are already tested
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12. Pressure Systems – Leak Testing
Transfer line shield and 4 K supply process piping field welds have been leak tested
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13. Pressure Systems – Leak Testing
Cryo can to transfer line welds will be tested when completed in the near future. Currently being welded.
Shield supply, shield return, 4 K supply, 2 K return process piping welds
300 K supply circuit
Fast cooldown line
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14. Pressure Systems – Summary
Analysis complete
PS-1
PS-3
PS-6
PS-7
PS-8
PS-9
Installation in progress
Leak testing in progress
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15. Cryo Processes - Outline
Introduction
Procedures
Risk Mitigation
Summary
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16. Cryo Processes - Introduction
LERF LCLS-II CM testing procedures were established in collaboration with JLAB’s Cryogenic Group to ensure safe operation and to mitigate impact to CEBAF operations
U-tube Stabbing procedure based upon existing procedures
Cooldown procedure
Temperature Bump procedure
Warm Up procedure
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17. Cryo Processes - Introduction
Prerequisites
Process lines cleaned and purged
CHL shall be at 4 K during u-tube operations to manage potential contamination
Signal verification of all instrumentation according to procedures
FL02 is cold and providing additional heat (200W) to establish stable return pressure
Approved ATLis for each process ensuring all relevant parties are informed
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18. Cryo Processes – Procedures - Cooldown
Initial CM cooldown from 300 K
Simultaneously cool both CMs
Preliminary Steps:
Instrumentation signal verification
Valves, vac, LL-gauges, P-transducers, T-diodes, and flow meters
Strip Charts
GHRP diodes
LL gauges
Helium pressures
Valve positions
U-tube installation
Create ATLis and ensure it has been reviewed by Cryo Group
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19. Cryo Processes – Procedures - Cooldown
Shield Cooldown
~ 3 g/s at operating T
Operating temperature of 35 – 60 K
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20. Cryo Processes – Procedures - Cooldown
Primary Cooldown
RT valve closed
Both CMs simultaneously
CMCD and JT valves open
CD bypass valve open
Flow controlled to limit CM pressure to 1.5 atm
JT valves closed when 4 K lines at 50 K
GHRP Tavg < 80 K, primary supply full open
Liquid formation – Close CMCDs
JTs set to 78% upsLL
After soak (24hr), Close JTs
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21. Cryo Processes – Procedures - Cooldown
Primary Cooldown cont’d
Open RT- Cryo Group monitors return pressure
When return-P < .045 atm, JTs set to 90% upsLL
Cryo Group to assist in RT valve setup for steady state ops
Cryo Group to perform RT pumpdown to 2 K
Primary supply 100% upper limit once stable
JTs set to 90% upsLL
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22. Cryo Processes – Procedures – Temperature Bump
To expel remanent magnetic field from the cavities
One CM at a time, up to 40K and back down to 4K
Preliminary Steps:
Strip Charts
Diodes
LL gauges
Helium pressures
Valve positions
Create ATLis and ensure it has been reviewed by Cryo Group
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23. Cryo Processes – Procedures – Temperature Bump
RT closed
CD bypass valve open
Cryo Group – Open SLINAC CD valve (transfer line CD header to recovery)
CM2 CD heater on
CHL recovery 1.08<P<1.09 atm
Cavity HV at 40 K → Heater off
HEATER
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24. Cryo Processes – Procedures – Temperature Bump
FCD
Cryo Group to monitor SLINAC Cold compressor speed
Open CM2CD valve
Cavities at 4 K, close CM2CD and set CM2JT for 80% upsLL
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25. Cryo Processes – Procedures – Temperature Bump
CM2JT is closed and the same steps are then performed for CM1
CD bypass valve is closed and the RT valve is opened
The opening of the RT valve is controlled by the Cryo Group as they monitor return pressure and cold compressor stability
RT valve is fully opened and disconnected from controls
JT valves are set to maintain 90% upsLL
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26. Cryo Processes – Procedures – Warm Up
To warm the CM back up to 300 K after testing
Both CMs simultaneously at a rate acceptable to Cryo Group
Preliminary Steps:
Strip Charts
Diodes
LL gauges
Helium pressures
Valve positions
Create ATLis and ensure it has been reviewed by Cryo Group
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27. Cryo Processes – Procedures – Warm Up
Close the 4 K supply valve
Close the RT valve
Open CD bypass valve
Maintain return line P<1.05 atm
Close JT valves
Open CMCD valves
HV heaters on until dwnsLL<20%
Maintain CHL recovery P<1.09 atm
Open 300 K supply valve ~1.5g/s
Incrementally increase insulating vacuum space pressure
GHRP T>285 K, heaters off
Close 300 K supply valve
HEATER
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28. Approach for Risk Mitigation
Design modified after review to require only one set of u- tube operations at initial 4K cooldown and removal after warm-up
Fast cooldown down via atmospheric return (4K)
Max flow rate dictated by stable operations of vacuum
No plans for FCD thru 2K return transfer line
Majority of operations is single cavity testing (up to 20 W dynamic) with FL02 heater energized at 200W
Multi-cavity operations will happen only after all cavities have been characterized individually and ATLis is approved

29. Cryo Processes – Risk Mitigation (1/2)
PROCESS/STEP
RISK
MITIGATION(S)
Primary cooldown/Open RT valve-step 11c
Overpressurization of return header, trip CHL
Cryo Group will monitor parameters and direct opening rate during pumpdown
Temperature bump/heater warm up-step 9
Cryo Group will monitor recovery pressure. Heater power dialed back
Temperature bump/Open CM CD valve-step 15-17, 29-31
Cryo Group will monitor the cold compressor speed. Adjust CM-CD valves
All/State of EV and Manual valves on Cooldown header
Potential connection between subatmospheric and atmospheric return paths if RT is open simultaneously
Administrative tag on manual valve with state change requiring Cryo Group concurrence. CEVCD disconnected;
Consider disconnecting atm return line
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30. Cryo Processes – Risk Mitigation (2/2)
PROCESS/STEP
RISK
MITIGATION(S)
CM steady operations
Instability in 2K return TL causing pressure oscillations at Cold Compressors
Require 200 W heater heat in FL02
CM steady operations / Cavity Testing / RF ON
Excessive power into primary return due to dynamic heating
Single cavity testing with constant heat (200 W) in FL02
Overfilling helium volume with spill-over into return piping causing pressure oscillations
“A” loop on primary JT closes when pressure exceeds specified limits
Overloading SLINAC cold compressor
Cryo Group will monitor the cold compressor speed. Adjust CM-JT valves
CM steady operations / 2K RT Valve operations
Instability in 2K return TL causing pressure oscillations at Cold Compressors leading to trip
Calibrate RT valve actuator LVDT; Consider verifying leak tightness of RT valve
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31. Processes – Summary Preliminary Cooldown procedure developed
Preliminary Temperature Bump procedure developed
Preliminary Warm Up procedure developed
Scenarios that could negatively impact CEBAF CHL operation are understood and able to be mitigated
Cryogenics Group has collaborated in the development of the procedures
11/12/2018

32. Summary Pressure System Program Analysis complete
Completed PS-forms filed
Installation and leak testing in progress
Procedures
Preliminary procedures written
Cryogenics Group has collaborated in the development of the procedures
Procedures will continue to be updated based on feeback from initial testing observations
11/12/2018