Dufrane Nuclear Shielding Inc (DNSI) has successfully performed multiple projects at the Oak Ridge National Laboratory , within the High Flux Isotope Reactor (HFIR) and the Spallation Neutron Source (SNS)

DNSI was selected by ORNL as the sole source to the prime contractor. DNSI designed and fabricated three Saddle Shield Assemblies for the HFIR Horizontal Beam Lines designated HB-1, HB-2 and HB-3. The Saddle Shields were intricate steel framed molds which were mated with the prime contractor’s rotating Monochromators with multifaceted surfaces. Sheets of HDPE material were placed to protect the Monochromator’s surfaces and maintain the specified clearance. DNSI placed and secured the Saddle Shield adjacent to the Monochromator and proceeded to place our High Density Concrete in a continuous pour within the form. This created an integral steel and concrete Saddle Shield assembly. The resulting 1/32” clearance between the Shield and Monochromator was described by HFIR personnel after installation as surpassing their anticipated engineering criteria.

As a follow up to the Saddle Shield project, DNSI was selected to provide High Density Concrete Floor Blocks for the HFIR HB-2 experiment area. DNSI provided Standard Density, High Density and Steel Encased High Density Concrete Shield Blocks for multiple Beam Lines within the facility’s Target Building. Beam Line-2, Backscattering Spectrometer: A total of 31 forms and 10 Steel Encasements were required to be designed and fabricated. These were utilized to provide a total of 83 Shield Blocks the heaviest of which was 36,000 pounds. At the Spallation Neutron Source Facility Beam Line-11A, Backscattering Spectrometer: DNSI also provided shield blocks for Beam Line-12, Single-Crystal Diffractometer (TOPAZ).