Electron Beam Welder

  • Sciaky 60 kV, 1-700 mA electron beam, six axis CNC controlled manipulator
  • 68" x 68" x 84" stainless steel chamber
  • Clean vacuum system: Edwards GXS450/2600 dry screw type roughing pump backing a 16,000 l/s cryo-pump, capable of 5 x 10-5 torr in less than 10 minutes, baseline pressure 1 x 10-6 torr.
  • Low vapor pressure lubricants
  • Located within a Class 10,000 cleanroom

The Jefferson Lab Electron Beam Welding Facility comprises a Sciaky 60 kV, 1-700 mA electron beam, CNC six axis  computer- operated electron gun welding heat source inside of a 68" x 68" x 84" stainless steel vacuum chamber. The vacuum system has an Edwards GXS450/2600F Screw Pump/Roots Booster Combination backing a 16,000 l/s CTI cryo-pump capable of achieving a chamber vacuum better than 5 x 10-5 Torr. Fusion welding of the niobium superconducting cavity assemblies is the primary role of the facility although weldment assemblies of copper, aluminum, and stainless steel materials are performed regularly. Assemblies are precision prepared, cleaned, and placed in the vacuum chamber for computer controlled manipulation via the CNC G-code controller and monitoring station also located within the facility room


  • Super clean welding (to preserve the superconducting quality) of the Niobium, full penetration welds from 0.005" to 0.75" thickness - no filler material used. Parts are precision fit and fusion welded
    • Hundreds of Nb parts fabricated for CEBAF construction
    • Prototype Nb cavities for SNS and RIA and CERN
    • Hundreds of cavities for CEBAF and FEL upgrade cryomodules
    • Many prototype cavities for the 12 GeV Upgrade cryomodule
    • Hundreds and hundreds of R&D cavities for JLab students and collaborators
  • Stainless steel (304 & 316) 0.010" to 0.875"
  • Copper, aluminum, titanium, tungsten, alloys also undertaken in the Jlab 'E-Beam' facility