1. Hongyu Bai LCLS-II 2 K Cold Box PDR September 27, 2016
Safety and ESH
Hongyu Bai
LCLS-II 2 K Cold Box PDR
September 27, 2016

2. Outline 2K coldbox and interfaces Pressure safety Design pressure
Pressure relief in the 2K coldbox
Pressure relief at the interfaces
Other safety issues
What-if analysis
Summary
LCLS-II 2 K Cold Box PDR, Sept 27, 2016

3. 2 K Cold Box Components 5 CC + 1 CC with motors and magnetic bearing
Process piping
Bayonets
Flow straightener
Vacuum Jacket
With manhole
Vacuum pumps
Relief devices
Control valves
MLI
Instruments
LCLS-II 2 K Cold Box PDR, Sept 27, 2016

4. 2 K ColdboxInterfaces LHe dewar To 4.5K CBX U-tube Clean up return
From Interface Box
Vacuum Break
Instrument Air
Cooling water
3 atm He
Guard Vac.

5. Design pressure requirement
Component
Normal operating
Design Pressure
Pressure
Temperature
Vacuum jacket
~ 0 bara
~ 300 K
External 1 bara
Internal 0.2 barg
Discharge piping to 4.5 K coldbox
1.2 bara
~ 27 K
6.2 bara
Suction piping and CCs piping
0.027 bara
3.4 – 27 K
4.1 bara
LHe dewar vapor return piping
1.25 bara
4.5 K
3 atm Helium supply
4 bara
300 K
11.2 bara
LCLS-II 2 K Cold Box PDR, Sept 27, 2016

6. Pressure rating of components
3-1/8” bayonets (LHe dewar 4.5K Vapor return)
12.4 bara [1]
5-3/16” Bayonets (30K discharge U-tube)
6.2 bara [1]
9-1/4” female bayonets (on Interface Box)
5.1 bara [1]
CC motor cartridge
47 bara [2]
CC wheel housing
4.1 bara [2]
Cryogenic valves
> 10 bara
[1] LCLSII-4.8-EN-0791-R0, Jlab bayonet gate valves
[2] LCLS-II cold compressor technical proposal, ALAT
LCLS-II 2 K Cold Box PDR, Sept 27, 2016

7. Operating Temperature
Interfaces
No.
Interface
Connection
Operating pressure
Operating Temperature 1
30 K discharge to 4.5K CBX
5-3/16” bayonet
~ 1.2 bara
25-30 K 2
3.5K suction line
10” internal pipe
weld connection
~ 27 mbara
~3.5 K 3
4.5K vapor from LHe dewar
3-1/8” bayonet
~ 4.5 K 4
Cleanup return
1/2“ internal pipe
weld
300 K 5
RT He supply
1” pipe
4 bara 6
Guard vacuum
Weld
< 10 Torr 7
Instrument air
~ 7 bara 8
Cooling water
1” pipe weld
~ 5 bara
~ 300K
LCLS-II 2 K Cold Box PDR, Sept 27, 2016

8. Utilities 1. Cooling water (For CC and Diffusion Pump)
Pressure drop: <1bar
Pressure head of water pump at SLAC: ~ 70 psi
2. Vacuum guard (For CC and bayonets)
Vacuum will be used for the sealing intercept instead of helium. Helium guard is provided as an option.
Relief plate set pressure: 1.2 bara
3. Instrument air
For 6 pneumatic control valves
Required pressure of 7 bara
Safety valve set pressure: 11.2 bara
LCLS-II 2 K Cold Box PDR, Sept 27, 2016

9. The reliefs are designed to:
Safety Relief System
The reliefs are designed to:
Ensure safety in all modes (normal, failure, partial maintenance, etc.)
Adequately relief system for all types of failures
Prevent contamination during normal operations
Reseal to maintain system integrity, minimize helium loss
Vent outdoors for process piping
Safety valve in guard vacuum
LCLS-II 2 K Cold Box PDR, Sept 27, 2016

10. Sub-atmospheric pressure Line B
U-tube
Safety relief setting
2 K Coldbox:
Safety valves are installed at suction
and discharge
U-tube
Vacuum Break
CM process lines are protected at DB
(FNAL):
Safety valve relief at 2 bara
Burst disk relief at 4 bara
LCLS-II 2 K Cold Box PDR, Sept 27, 2016

11. Subatmospheric System Relief
Name
Cryomodules & CDS
(FNAL Scope)
2K CBX suction
2K CBX discharge
Operating pressure
31 mbar ( normal operation)
1.2 bara (Cooldown)
27 mbara ( normal operation)
<= 1.2 bara (Cooldown)
1.2 bara
Safety Relief Pressure
2 bara (at RT)
4 bara (at LT)
4.1 bara
6.2 bara
Location DB
2 K CBX
2 K VBX
Type
Spring loaded valve
Burst disk
ASME, guard vac. enclosure
ASME, guard vac. enclosure
Vents to
Outdoors
LCLS-II 2 K Cold Box PDR, Sept 27, 2016

12. Preserve inventory in the event of total power failure
Blowdown
“Low pressure” relief for long term power outage.
Preserve inventory in the event of total power failure
LCLS-II 2 K Cold Box PDR, Sept 27, 2016

13. Safety valves Primary relief valve requirements
RV41712: static heat in-leak cavities at 4.5 K liquid
RV41722: Thermal expansion in the case of loss of vacuum in 2K CBX
RV41175/RV41200/RV41500:Thermal expansion in the case of loss of vacuum in 2K CBX
RV41000: Vacuum Jacket protection
Standards:
ASME B “Process Piping”
ASME BPVC Section VIII Div. 1 – 2015 “Rules for construction of Pressure Vessels”
API 520 – Part I 2014, “ Sizing, Selection, and Installation of Pressure Relieving Devices on Refineries, Part I-Sizing and Selection”
CGA S “Pressure Relief Device Standards”
LCLS-II 2 K Cold Box PDR, Sept 27, 2016

14. Oxygen Deficiency Hazard (ODH)
Fluid: Helium
colorless, odorless, tasteless, non-toxic, inert
Helium volume:
Normal operation: < 10 Liter LHe (equivalent)
Cooldown: < 100 liter LHe (equivalent)
(~ liters in CMs.)
ODH in the coldbox room has been analyzed and reviewed. SLAC ES&H Program Manager Concurrence.
ODH class of Cryo building: class I
Warning Signs
Installed Oxygen Monitor
Ventilation
Training for personnel
LCLS-II 2 K Cold Box PDR, Sept 27, 2016

15. Electrical Electricity 480 VAC +/-24V 3 phase – 60Hz +/-1Hz,
13 kW/16 kVA for each CC motor.
The electrical components will follow the following standards:
IEC : 2005 / A1:2008, Safety of machinery
– Electrical equipment of machines
IEC : 2005 , Electromagnetic compatibility (EMC) –
Part6: Generic standards –
IEC : 2006 / A1: 2011
Electromagnetic compatibility (EMC) –
Part6: Generic standards
IEC
Safety requirements for electrical equipment for measurement, control, and laboratory use
LCLS-II 2 K Cold Box PDR, Sept 27, 2016

16. Noise
The expected noise generated by the cold compressors will be lower than 85 dB when measured from 1 m distance from equipment [1].
The National Institute for Occupational Safety and Health (NIOSH)
Allows all worker exposures to noise no more than 85 dBA for eight hours to minimize occupational noise induced hearing loss.
The standards for occupational noise exposure adopted by the DOE
State that personnel without hearing protection must not be exposed to an intensity of noise exceeding 85 dBA.
[1] LCLS-II cold compressor technical proposal, ALAT
LCLS-II 2 K Cold Box PDR, Sept 27, 2016

17. Cold burn, etc Cold burn: Lowest temperature: 3.5 K
The cryogenic pipes and equipment are vacuum insulated.
Fall protection
Height: 12.5 feet
A platform will be built around the 2 K coldbox for maintenance.
Confined space:
A manhole on the side and a ventilation hole on the top provided for installing upgrade/downgrade piping spools inside.
Any maintenance inside 2 K CBX jacket will be planed, reviewed and approved according to ESH manual Chapter 6.
Seismic: to be completed
LCLSII-4.8-EN-0227 “LCLS-II Engineering Note on Cryogenic Plant Seismic Design Criteria”
LCLS-II 2 K Cold Box PDR, Sept 27, 2016

18. What-if analysis
What-if analysis for the 2 K CBX has been performed and an EN was drafted.

19. Summary
The related ES&H aspects are identified and addressed in the 2 K cold box design.
Integrated pressure safety relief is designed in the 2 K cold box, cryoplant and CDS.
What-if analysis was performed for the 2 K coldbox.
LCLS-II 2 K Cold Box PDR, Sept 27, 2016

20. Thank you!