2K Cold Box Process Design Vishy Ravindranath LCLS-II 2 K Cold Box FDR Mar 28, 2018

Outline Introduction Process Requirements 2K CB P&ID 2K CB Major Components: Control Valves 2K CB Flowmeters 2K CB Relief Valves

Introduction LCLS-II (x1 CP) LCLS-II (1 CP) C1 2K CB C2 2K CB IB IB DB DB C1 2K CB C2 2K CB L0, L1 & L2 L3 LCLS-II (1 CP) 37 CM: 1.3GHz, (x35) + 3.9 GHz (x2) Single CP Operation U-Tubes between Interface Boxes Welded Interface

2. Process Requirements:4K CB & 2K CB Maximum Capacity 2K CB Capacity (Ref: 2K CB Technical Specification, 79222-S001) Mode Flow [g/s] Inlet Temp. [K] Inlet Press. [mbar] Outlet Temp. [K] Outlet Press. [bar] Max 215 3.5 27 < 30 1.2 Min 150 3.6 28 4K CB Capacity Ref: 4.5K CB Technical Specification, LCLSII-4.8-CT-0284 Cavities (2K) Warm Shields (35-55K) Intercepts (5-8K) Liq. 4K CB Max Cap. 4.0 kW (200 g/s) 15 kW 1.30 kW 15 g/s Linac Heat Load (Qo = 2.7E10) 3.7 kW (180 g/s) 1.39 kW Max 2K Ref Cap. = 200 g/s Limited by 4K CB Capacity 15 g/s Liq. : Provides additional margin for the Intercept and the Warm Shield Loads

2. Process Requirements: Linac 2K Heat Load (Mass Flow) Cryoplant Capacity = 4 kW Operating Margin wrt Cryoplant Capacity of 4 kW (200 g/s)

2. Process Requirements: Heat Loads & Pressure Drops C1-2K CB C1-4K CB Line A Line B QDis Heat Load and Pressure Drop compiled in LCLS-II-4.8-EN-0804-R0 “LCLS-II 2K Cold Box Process Analysis” QDis QCM QCM

3. 2K CB PID LHe Dewar Clean up return Safety Reliefs To 4.5K CBX Sub-atmospheric pressure He gas from cryomodules returns to the suction of CCs and is compressed from ~ 27 mbar to 1.2 bar in the 2 K coldbox. The compressed gas returns to 4.5K coldbox through an U-tube. For the test of 2 K CBX with LHe dewar, 4.5K cold vapor from LHe dewar is used to simulate the flow, with a 3 kW heater for controlling the helium temperature in the suction line. A bypass line for the overall CC train is included for 4.5K standby operation mode and pumping down. Safety valves are used for the protection of the 2 K coldbox, CC and process piping. Pressure and temperature measurement are installed at the suction of each CC and on the discharge pipe. A flow meter is installed in the discharge pipe of CCs for flow measurement and controlling of CC. The 2K coldbox provides vacuum insulation for the cryogenic part of CCs and the cryogenic process piping. Clean up and warm up piping are included. Utility piping (Instrument air, cooling water and guard vacuum) are included. CC Bypass 2K RET From LINAC CM

3. 2K CB P&ID: Interfaces Int No. Interface Bayonet Size Component Pressure Rating [psig] Operating Temperature He-504 CC5 Discharge 5-3/16” 75.1 4-300 He-505 CC6 Suction He-506 CC6 Bypass He-507 30K return from 2K Cold Box to 4K Cold Box He-508 4K vapor supply from LHe storage dewar to CC1 suction 3-1/8” 83.2

3. 2K CB P&ID: Interfaces Int No. Interface Connection ComponentRating [psig] Operating Temperature [K] He-501 CC1 suction 10” pipe welded 45 4-300 He-510 Cleanup return ½” pipe weld 150 300 He-511 3 Atm He supply 1” pipe weld GV-512 Guard vacuum 1” pipe weld Vacuum-15 IA-513 Instrument air He-515 Relief Valve Discharge Collector 3” KF Flange 15 CW-517 Cooling water Supply 2” pipe weld 100 CW-518 Cooling water return ~300

4. 2K CB Major Components: Control Valves Valve Tag Valve Descr. Valve Size NPS Max Sizing Scenario Req. Cv Max. Cv PV41500 Dewar 4K Supply 1.5 Pump Down Mass flow = 300 g/s Inlet Pressure = 1.25 bara Inlet Temperature = 4.5 K 40 52 PV41212 2K Bypass 2 4K Linac Operation Mass flow = 490 g/s Inlet Pressure = 1.5 bara Inlet Temperature = 4.7 K 43 PV41160 CC Discharge 4 Inlet Pressure = 1.2 bara Inlet Temperature = 30 K 202 302 PV41565 PV41170 Control Valves are sized in accordance with Flow Equations For Sizing Control Valves - ANSI/ISA-75.01.01 (IEC 60534-2-1 Mod)-2007. 2K CB Bypass Valve –PV41212 size was increased from 1” to 2” valve. 2” valve allows 9 kW of Ref. Capacity for 4.5K Linac Operation (with RF) 3. 2K CB Control Valve Data Sheet documented in JLAB Spec: 79720-S007, Technical Specs for LCLS-II Cryogenic Control Valves (PV41212 updated spec communicated to Valve vendor by JLAB)

4. 2K CB Major Components: Flowmeter Tag Description Size NPS Throat Size Max Sizing Scenario ∆P_cal (mbar) ∆P_FS (mbar) F41200 CC Discharge 4 1.8 m = 260 g/s P_in = 1.25 bara T_in = 30 K 66 100 F41500 Dewar 4K Supply 2 1.2 m = 300 g/s T_in = 4.5 K 38 50 Flows considered for the sizing are based on CHL-II 2K Cold Compressor Flow Data The flowmeters are sized in accordance with : “Measurement of Fluid flow by means of pressure differential devices-Part 1: ISO 5167-1 (1991)”. 2K CB Flowmeter Datasheets documented in JLAB Spec: 79420-S010, Technical Specs for LCLS-II Venturi Flow Elements 280 g/s CC mass flow 200 g/s CC5 Discharge Pressure = 1.2 atm CC5 Discharge Temperature 30 K 6K

4. 2K CB Major Components: Relief Valves 2K Cold Box Safety Reliefs are designed to: Adequately relieve the system and protect the process pipes/components within the 2K Cold Box against worst case failure scenarios. Relief Valves mounted within Guard Vacuum Enclosure: (protected by parallel plate with 2 psig set pressure): Prevents contamination of sub-atmospheric process lines during normal operations 3. All reliefs vent into a common relief header which is routed outside the building to vent the gas in a safe manner 4” Relief Discharge Collector

“79222-P0001 2K Cold Box Relief Valves” 4. 2K CB Major Components: Codes for Relief Valve Sizing Relief Valve Sizing Calculations documented in: “79222-P0001 2K Cold Box Relief Valves” Standards & References: API 520 – Part I 2014, “ Sizing, Selection, and Installation of Pressure Relieving Devices on Refineries, Part I-Sizing and Selection” CGA S-1.3-2008 “Pressure Relief Device Standards” ASME Code Section VIII, Division I, Appendix 11, Mandatory Capacity Conversions for Safety Valves

4. 2K CB Relief: Heat Leak Assumption Node# Nominal Pipe Size Length Surface Area Heat Leak [in] [m] [m2] [kW] #1 2 9 2.4 #2 10 6 20 30 8 11 4 2 1/2 5 #3 #4 7 2.7 #5 2.0 3 #6 For 2K CB thermal relief valve sizing based on heat flux assumption of 1500 W/m2 “Safety Aspects for LHe Cryostats and LHe Transport Containers,” W. Lehman and G. Zahn, ICEC7, London, 1978 (Fig 7): 6000 W/m2 for cryostat with 10 layers of MLI (super insulation) 1300 W/m2 for cryostat 1” thick layer of MLI 2K CB process pipes have 60 layers of MLI

4. 2K CB Major Components: Reliefs Failure Scenario: Loss of 2K CB Insulating Vacuum Heat Inleak into Process Lines due to air condensation Tag Mass Flow [g/s] Req. Orifice Size [in] Sel. Orifice Size [in] RV41500 79 0.18 0.29 RV41530 1340 0.80 0.92 RV41540 274 0.36 0.44 RV41550 133 0.23 RV41565 94 0.19 RV41560 136

4. 2K CB Major Components: Relief Valve Vent Line Pressure Drop Ins. Vac ΔP = 6 psi Seg#1: 3” relief discharge manifold ΔP = 2 psi Pr = 45 psig ΔP = 1.4 psi PL = 66 psia = (45 + 14.7 + 6) ΔP = 2.4 psi Air Leak Pv = 14.7 psia Seg#2: 4” Parallel Plate Vent Flow Rate = 2 kg/s - All reliefs vent simultaneously Pressure Drop in Vent Line (Back Pressure) = 6 psid Differential Pressure on the Process Line = 51 psid Cold compressor casing design pressure = 60 psid. Seg#3: 6” Relief Header ΔP = 0.4 psi Vents to outside the Bldg.

Summary The cold compressor design accommodates the anticipated variation in the heat load. The design & interface requirements for the 2.0 K Cold Box have been identified on the P&ID. Relief Valve calculations have been performed for the 2K cold box. The calculation details have been documented and reviewed Detailed supporting calculation documents been developed: Document No. Title Status LCLSII-4.8-EN-0804 LCLS-II 2K Cold Box Process Analysis Released JLAB-79720-S007 Tech. Spec for LCLS-II Cryogenic Valves JLAB-79120-S010 Tech. Spec for LCLS-II Venturi Under Review JLAB-79222-P0001 2K CB Relief Valve Sizing 79222-0000 2K Cold Box P&ID

Background LCLS-II 2 K CBX FDR, Mar 9, 2017

Non Cryomodule-Heat Loads Document No. Title LCLSII-4.8-EN-0804-R0 LCLS-II 2K Process Analysis LCLSII-4.5-EN-0179-R2 Cryogenic Heat Load LCLSII-4.9-EN-0299-R1 LCLS-II CDS Heat Leak Analysis

Line B Pressure Drop for LCLS-II (1CP) 11 m 50 m 30 m Int. Box 107.5 g/s 107.5 g/s Pressure Drop in Line B for LCLS-II Baseline ~ 4 mbar