LCLS-II Prototype Cryomodule Vacuum Vessel and HGRP Tom Peterson 4 December 2014 Design Review

2 Objectives We have long recognized in our schedule that two of the longest lead items for the prototype cryomodules are the vacuum vessels and the helium gas return pipe (HGRP) weldments. Last October, we decided that in order to get a head start on these procurements for the prototype cryomodules, as opposed to waiting until after the 22 January cryomodule FDR, we should hold an engineering peer review for these two specific items (and also for the helium vessels, which became a separate review). Fundamental questions to be answered in this review are: -Are we ready to proceed with procuring the two prototype cryomodule vacuum vessels? -Are we ready to proceed with procuring the two prototype cryomodule HGRP welded subassemblies? We recognize that some work remains. We will provide the status of the work. Vacuum Vessel and HGRP review, 4 Dec 2014

3 Agenda Introduction -Presentations and documents are posted at -Requirements -Interfaces including instrumentation ports on the vacuum vessel -Mechanical design status Vacuum vessel design status -Drawings status -Analysis and documentation status HGRP design status -Drawings status -Analysis and documentation status Safety and compliance with standards Risks Prior experience (XFEL, CM2, etc.) Vacuum Vessel and HGRP review, 4 Dec 2014

4 Technical Requirements Physics Requirements Document: LCLS-II Parameters, LCLSII-1.1-PR-0133-R0 Functional Requirements Specification: 1.3 GHz Superconducting RF Cryomodule, LCLSII-4.5-FR-0053-R0 -Most requirements are in this document, see next slide Cryogenic Heat Load, LCLS-II-4.5-EN-0179 (has no effect on the vacuum vessel nor HGRP) Seismic Design Specification for Buildings, Structures, Equipment, and Systems: 2014, SLAC-I-720-0A24E-001-R004 Interface Control Document: Cryogenic Distribution System, LCLSII-4.9-IC R0 We have a draft Cryomodule Interface Requirements Document (more about that later) (No cryomodule Engineering Specification Document exists yet) Vacuum Vessel and HGRP review, 4 Dec 2014

5 From LCLSII-4.5-FR-0053-R0 (Cryomodule FRS) Vacuum Vessel and HGRP review, 4 Dec 2014 DOE and laboratory standards -10CFR851, Fermilab’s FESHM 5031, etc. Maximum allowable working pressures (MAWP) -Including for the vacuum: 1 atm external with full vacuum inside 0.5 positive differential internal -And for the HGRP 2.0 bar warm 4.0 bar cold Vacuum Alignment Etc.

6 Interface Requirements We have a draft interface requirements document, based on: -Fermilab’s CM2 interface document -Our cryomodule integration meetings at SLAC on 21 and 22 October, Topics discussed at SLAC on 21 – 22 Oct included: Alignment Vacuum Instrumentation Installation -Ongoing communications with vacuum, instrumentation and others Vacuum Vessel and HGRP review, 4 Dec 2014

7 Instrumentation, P&I Diagram, vacuum ports Vacuum Vessel and HGRP review, 4 Dec 2014 The Cryomodule Process and Instrument (P&I) diagram, cryomodule instrument list, and a draft cryomodule interface document are posted to the Indico site. The P&I diagram is a signed and released drawing. The Instrument list and interface documents are still being developed, although the instrument list is nearly done. The relevance to these procurements is that we are providing a suitable array of vacuum vessel ports -Instrumentation connectors are allocated to ports with some extra space -8-inch vacuum venting port -Tuner access ports

8 Mechanical Design Status Drawings are complete but not signed off (waiting for input from this review) -Vacuum vessel -HGRP assembly -Drawing notes include all fabrication specifications. (Prior procurements did not involve separate fabrication specifications other than the drawings.) Yun He’s vacuum vessel analysis is in progress for checking compliance with Fermilab’s vacuum vessel standard (FESHM 5033) Zhijing Tang’s cryomodule analysis is in progress for checking seismic loading issues -First look indicates that neither the vacuum vessel nor the HGRP will be affected by those considerations -Attachments through the support posts and/or attachments to the floor plates will be the weak links in the load path between cold mass and floor The HGRP will also be an element of the piping in our ASME piping code analysis (FESHM ) Vacuum Vessel and HGRP review, 4 Dec 2014

9 HGRP in cross-section Vacuum Vessel and HGRP review, 4 Dec 2014

10 Liquid helium management Vacuum Vessel and HGRP review, 4 Dec 2014 Orientation of the connection to the 2-phase line is designed with liquid helium containment in mind.

11 Thermal and Helium Flow Design HGRP thermal and pressure drop analyses have been completed in conjunction the the cryogenic distribution system, as we design the piping as a full system Vacuum vessel emergency venting -We assume full break of one pipe -Worst case is the 2 Kelvin supply or 5 Kelvin thermal shield line, since those have the greatest potential to provide mass flow into the vacuum vessel -One 8-inch relief port on the top of each cryomodule -The 8-inch relief ports in a string of cryomodules act in parallel -The worst case is L0, with only one cryomodule -Analysis is in progress Vacuum Vessel and HGRP review, 4 Dec 2014

12 Risks Both these procurements are low risk -Very similar to Fermilab’s prior procurements for ILC prototypes -We are in communication with DESY and Saclay regarding XFEL experience with these components Risk of some out of tolerance discovery with QC -Result is a schedule hit -Mitigation: only qualified vendors will bid, based on prior deliveries -XFEL experience shows (again) need for diligent oversight of vendors Vacuum vessel port size / location change -Cavity spacing is set (reference?) -Instrumentation list and P&I diagram are mature -Tuner access ports are inexpensive and low risk Additional cost for a single $140 K vessel estimated as 11% by vendor Vacuum Vessel and HGRP review, 4 Dec 2014

13 Safety and compliance with standards Fermilab safety standards which apply to the vacuum vessel and HGRP (Piping Systems) (Cryogenic System Review) (Vacuum Vessel Safety) These result in two Fermilab engineering notes -One for the piping system -One for the vacuum vessel A full package of documentation including these engineering notes but also including P&I diagrams, pressure vessel documents, venting analyses, operating procedures, what-if analysis, Failure Mode and Effects Analysis (FMEA), and more, are required for a Cryogenic System Review -Which is really an operational readiness review for the cryogenic system Vacuum Vessel and HGRP review, 4 Dec 2014

14 Lessons Learned QC experience from DESY / XFEL Assembly experience from CM1, CM2 Vacuum Vessel and HGRP review, 4 Dec 2014

15 Costs and Schedule NO cost and schedule information will be included in the slides for this presentation. Schedule information will be provided at the review. Vacuum Vessel and HGRP review, 4 Dec 2014

16 Summary Vacuum vessel and HGRP drawings are complete Other documentation is in advanced draft stages Analyses indicate no problems for these designs with respect to mechanical or pressure requirements Prior experience at Fermilab and also collaborative relationship with DESY and Saclay as they make similar procurements reduces risk We propose moving ahead with procurement documents for vacuum vessels and HGRP weldments for the two prototype cryomodules Vacuum Vessel and HGRP review, 4 Dec 2014

17 Cryomodule mock-up for tuner access – 1 Vacuum Vessel and HGRP review, 4 Dec 2014

18 Cryomodule mock-up for tuner access – 2 Vacuum Vessel and HGRP review, 4 Dec 2014 View of tuner through the access port

19 SLAC Cryomodule Mechanical Model Vacuum Vessel and HGRP review, 4 Dec 2014 Space available along the wall looks better than one might expect

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