a method to reduce the gap between huellrohr and brennstoffuellung of kernreaktorbrennstaeben

摘要

Nuclear fuel rod cladding tubes are sized internally to diameters precisely fitting nuclear fuel pellets with which the tubes are charged, by externally applying hydraulic pressure to short lengths of each tube, the pressure being applied while the tube is stationary and the tube then moved to bring a new length within the hydraulic pressure zone. The volume of the hydraulic liquid used and the pressure applied to this liquid is such that the liquid is compressed slightly so that the length being sized yields, the expansion of the liquid then completing the sizing. The lengths being sized step-by-step are internally supported by either the fuel pellets or a mandrel having the same diameter as the pellets.