Non-Destructive Testing with Neutron Radiography at the UC Davis/ McClellan Nuclear Radiation Center

The UCD/ MNRC inherited NDT capabilities from the US Air Force and even though it is now mainly a research facility, it has kept this acquired asset performing at a production level. The UCD/MNRC facility is equipped with a hexagonal grid, natural convection water cooled TRIGA reactor designed to operate at a nominal 2 .0 MW steady state power as well as in pulse and square wave mode. The reactor utilizes a specially designed annular graphite reflector accommodating four removable units to accept four separate source ends of beam tubes. These tangential beam tubes lead to four large investigation bays with neutron radiography setting. The design basis for these beam tubes is to provide a path for primary thermal neutrons with minimum scattering and attenuation between the reflector inserts and radiography bays. Typical unperturbed beam parameters are summarized in the following: Each beam tube ends with a bulk shield as the primary beam stopper and a separate boron-included fast shutter to initiate and complete a neutron exposure. Traditional film system and more recently computed radiology system utilizing reusable storage phosphor imaging plate (SPIP) are extensively used as 2D imaging recording media. Bay 3 is designed with a charge coupled device (CCD) camera with system control hardware and software to perform 3D neutron tomography. Bay 4’s beam tube, different from the others, has an 11”-thick sapphire crystal filter to provide an even higher quality beam, i.e. much lower contamination from fast neutrons and gamma rays, for 2D neutron radiography. UCD/ MNRC is committed to offering state-of-the-art neutron imaging experiences for non-destructive testing projects. Our unique capabilities enable us to provide effective solutions to the customer’s needs. Providing quality assurance of complicated titanium castings for aircraft, inspecting metal loss of pressurized tanks for fighting forest fires, examining binding between corrosion-resistant coatings and base metal for spent fuel containers, are a few of many services rendered