Overview of Main Linac Cryomodule (MLC) Yun HE MLC Internal Review 9/5/2012Yun HE, MLC Internal Review1

Total 64 cryomodules Cryomodule unit 9.8 m long six packages of 7-cell cavity/Coupler/tuner a SC magnets/BPMs package five regular HOMs/two taper HOMs Cryomodule units are connected with no intervening warm breaks, and share a common insulation vacuum 9/5/2012Yun HE, MLC Internal Review2 Linac cryomodule Linac A 344 m with 35 cryomodules Linac B 285 m with 29 cryomodules 0.25 m Cold-warm transition Reduces cost and Linac length Requires entire warm-up for repairing nominal length: 9.8 m Beamline HOM absorber 7-cell cavity SC magnets & BPMs Intermodule unit

Cryomodule unit 9/5/2012Yun HE, MLC Internal Review3 All ports are on aisle side in the tunnel Coupler downstream of cavity SC magnets downstream of cavities Beamline string supported by HGRP via three posts Cryogenic valves Beam Pneumatic gate valve Manual gate valve Cavity package

9/5/2012Yun HE, MLC Internal Review4 Module interconnection Cryo-feed entry module Cryogen transfer pipes welded in situ Beamline interconnection unit connects two modules Slide intermodule unit Cryo pipes HGRP K 5K 2K Cryo-feed entry module, one for each linac Inserted between two cryomodules

9/5/2012Yun HE, MLC Internal Review5 Cross-sectional view of module HGRP Vacuum vessel 38” dia. OD Input coupler HGRP support post + alignment 40K shield + Mu-metal shield Rails 2K-2 Phase Cryogenic valves 4” 9.5”

9/5/2012Yun HE, MLC Internal Review6 HGRP 40K delivery 5K supply 40K supply 80K return 6.5K return Pre-cool/warm-up 2K supply 2K-2 Phase 40K local distribute 5K local distribute Cryogenic piping

Inside each cryomodule 7 Cryogenic Distribution 4 Valves control flow into local distribution lines: 2K Pre-cool 5K 40K 2K, 5K and 40K supply pipes run for the entire half linac 9/5/2012Yun HE, MLC Internal Review

Prototype cryomodule 9/5/2012Yun HE, MLC Internal Review8 Differences of Prototype Module from Linac Module Flange-to-flange length: 10.4 m Prototype moduleLinac module SC magnets/BPMsNoYes Wire position monitorYesNo Cryogenic feedingFront cryo-feed cap Side cryo-feed module Beamline warm-cold transitionYesNo Connection between HGRP & 2 phaseMiddle & endMiddle Cryogenic pipingWith flange/elbow pre-welded Straight Welded in-situ Intermodule unitReplaced by end capYes Cryo-feed cap End cap