Key Design Issues and Recent Reviews Tom Peterson, Fermilab DFBX PRR, October 23, 2002 US LHC ACCELERATOR PROJECT brookhaven - fermilab - berkeley

DFBX PRR 10/23/02Tom Peterson -- US LHC Project2 DFBX (feed-box) -- design status One of six design variants (BFBXC/G, points 2 and 8 left) is complete and released (271 drawings) Engineering and top level drawings for the other five design variants are done. Some detailed drawings remain (about 100 unique drawings)

DFBX PRR 10/23/02Tom Peterson -- US LHC Project3 DFBX design meetings at LBL within the past year December 11, 2001, review of results of November 2001 vendor fabrication study (PHPK and Meyer Tool, also Tom Peterson review of drawings) February (with Fermilab) April (with Fermilab, including Tom Nicol) June (with Fermilab and Don Brown) August 6-8 (Don Brown reviewing drawings) August (with Fermilab, including Kerry Ewald) September 4-5 (with Fermilab, Rob Van Weelderen and Vladislav Benda from CERN) September (with Fermilab)

DFBX PRR 10/23/02Tom Peterson -- US LHC Project4 Vendor fabrication study In October and November, 2001, PHPK and Meyer Tool reviewed the full (but at the time incomplete) set of drawings for DFBXC/G Their charge was to “review the designs for manufacturability, including suggestions for design changes that would lead to cost reductions or more rapid fabrication.” The issues outlined during the fabrication study set the design agenda for the past year. The recommendations have almost all been incorporated into the design. In particular, a lot of attention has been given to tolerances, one of the main vendor recommendations

DFBX PRR 10/23/02Tom Peterson -- US LHC Project5 Design issues and their resolution– tolerances and dimensioning Tolerances were brought to the highest possible assembly level, such that they define the actual requirement

DFBX PRR 10/23/02Tom Peterson -- US LHC Project6 Design issues and their resolution-- helium vessel design Helium vessel access port weld detail with provisions for cutting Helium vessel supports carry bus duct bellows pressure forces; bus duct gusseted for stiffness Attachment of power lead chimney to top plate of vacuum vessel Vessel meets ASME code except helium access door weld

DFBX PRR 10/23/02Tom Peterson -- US LHC Project7 Design issues and their resolution-- helium vessel support design Thin vertical invar rods carry vertical loads; helium vessel hangs from vacuum vessel top plate Horizontal invar rods carry axial loads and provide lateral stability Static and dynamic load analyses for the vessel and support elements are complete

DFBX PRR 10/23/02Tom Peterson -- US LHC Project8 Design issues and their resolution-- helium piping design Pipes hang from G-10 support plates in the vertical risers. Pipes are free to slide in the other support plates. Bellows remain only in the main bus ducts and large pumping line. Braided flex hose takes magnet interconnect motion as well as DFBX contraction; used extensively to prevent transmission of axial pressure loads at flex elements

DFBX PRR 10/23/02Tom Peterson -- US LHC Project9 Special design features-- lambda plate, buswork, current leads Lambda plate R&D phase at LBL including prototype is a success. LBL will produce a pre-production unit with full length leads.

DFBX PRR 10/23/02Tom Peterson -- US LHC Project10 Special design features-- lambda plate, buswork, current leads Completed specification for splicing superconducting leads and qualification contract with each vendor.

DFBX PRR 10/23/02Tom Peterson -- US LHC Project11 Special design features-- lambda plate, buswork, current leads Pirelli is expected to deliver the first pair of HTS leads in November. Testing of the leads will be at Fermilab.

DFBX PRR 10/23/02Tom Peterson -- US LHC Project12 Special design features-- lambda plate, buswork, current leads Completed specification and RFP for purchase of conventional vapor cooled leads.

DFBX PRR 10/23/02Tom Peterson -- US LHC Project13 DFBX remaining design details Some details for five remaining variants –Some new pipe routing arrangements –Variations of large pumping line supports –Variations of small pipe G-10 supports –Beam tube cooling details –These details are just “variations on a theme”

DFBX PRR 10/23/02Tom Peterson -- US LHC Project14 DFBX remaining design details Some interconnect weld details are not resolved with CERN but need not be resolved before contract is placed

DFBX PRR 10/23/02Tom Peterson -- US LHC Project15 DFBX remaining design details Some instrumentation details –Two instrument conduits are still under design. LBL will provide these subassemblies to the vendor. –Naming convention for magnet thermometers still not resolved with CERN –These are not problems for the RFP

DFBX PRR 10/23/02Tom Peterson -- US LHC Project16 Design status for RFP Engineering is complete for all boxes; remaining details are variations on the complete design and do not present any new engineering problems One drawing package is complete The vendors will have one complete design package with which to start making their estimates The vendors have requested the one complete drawing package, rather than our holding the package until the other details are complete The vendors will have all remaining details well before their final proposals are due

DFBX PRR 10/23/02Tom Peterson -- US LHC Project17 Design Summary The DFBX design has been very thoroughly engineered, documented and reviewed. Issues raised by the various reviewers including the vendors have been addressed in the design and documentation. Vendors will have the option to make modifications in order to follow their standard practices, reduce their cost, or speed up production, with LBL approval. But the vendors have an excellent, detailed design as a baseline guide. Fermilab will continue to work closely with LBL throughout the contract negotiations and fabrication.