A   B   C   D   E   F   G   H   I   J   K   L   M   N   O   P   Q   R   S   T   U   V   W   X   Y   Z    

Parma, V.

Paper Title Page
MPPT045 The Assembly of the LHC Short Straight Sections (SSS) at CERN: Project Status and Lessons Learned 2890
 
  • V. Parma, N. Bourcey, P.M. Dos Santos de Campos, R.C. Feitor, mg. Gandel, R. Lopez, M. Schmidlkofer, I. Slits
    CERN, Geneva
  
  The series production of the LHC SSS has started in the beginning of 2004 and is foreseen to last until end 2006. The production consists in the assembly of 474 cold masses housing superconducting quadrupoles and corrector magnets within their cryostats. 87 cold mass variants, resulting from various combinations of main quadrupole and corrector magnets, have to be assembled in 55 cryostat types, depending on the specific cryogenic and electrical powering schemes required by the collider topology. The assembly activity features the execution of more than 5 km of leak-tight welding on 20-bar design pressure cryogenic lines in stainless steel and aluminium, according to high qualification standards and undergoing severe QA inspections. Some 2500 leak detection tests, using He mass spectrometry, are required to check the tightness of the cryogenic circuits. Extensive electrical control work, to check the integrity of the magnet instrumentation and electrical circuits throughout the assembly of the SSS, is also carried out. This paper presents the current status of production, the assembly facilities at CERN, work organisation and Quality Assurance issues, and the acquired assembly experience after one and a half years of production.  
WPAE021 Short Straight Sections in the LHC Matching Sections (MS SSS): An Extension of the Arc Cryostats To Fulfill Specific Machine Functionalities 1724
 
  • V. Parma, H. Prin
    CERN, Geneva
  • fl. Lutton
    IPN, Orsay
  
  Funding: IPN-CNRS, 15 rue Georges Clémenceau 91406 ORSAY, France.

The LHC insertions require 50 specific superconducting quadrupoles, operating in boiling helium at 4.5 K and housed in individual cryostats to form the MS Short Straight Sections (MS SSS). The quadrupoles and corrector magnets are assembled in 8 families of cold masses, with lengths ranging from 5 to 11 m and weights ranging from 60 to 140 kN. The MS SSS need to fulfil specific requirements related to the collider topology, its cryogenic layout and the powering scheme. Most MS SSS are standalone cryogenic and super-conducting units, i.e. they are not in the continuous arc cryostat, and therefore need dedicated cryogenic and electrical feeding. Specially designed cryostat end-caps are required to close the vacuum vessels at each end, which include low heat in-leak Cold-to-Warm transitions (CWT) for the beam tubes and 6 kA local electrical feedthrough for powering the quadrupoles. This paper presents the design of the MS SSS cryostats as an extension of the arc cryostat’s design to achieve a standard and consequently cost-effective solution, and the design solutions chosen to satisfy their specific functionalities.