Abstract: Systems for controlling and protecting nuclear reactors. A drive of an emergency safety rod of a nuclear reactor includes an electric drive, a reduction gear, and a rack-and-pinion gear. The electric drive contains a contactless electric motor based on permanent magnets, which is installed in the housing of the electric drive with a motor rotor position sensor, and a reduction gear for changing the rate of rotation of the electric drive. A toothed rack is installed along the axis of the rack-and-pinion gear in order to provide for the reciprocating motion of a system absorber rod connected thereto. A toothed electromagnetic clutch having a contactless current supply is installed on an inner shaft of the rack-and-pinion gear, enabling the rigid and simultaneous mechanical coupling of half-couplings, and the drive contains a reverse-motion coupling, a rack-separation spring and toothed rack position sensors.

Abstract: The invention relates to nuclear physics, and specifically to reactor fuel elements and units thereof, and particularly to the composition of solid ceramic fuel elements based on uranium dioxide, intended for and exhibiting characteristics for being used in variously-purposed nuclear reactors. The result consists in a more reliable, special structure and a simple composition of uranium dioxide without heterogeneous fuel pellet additives, approaching the characteristics of a monocrystal having enhanced, and specifically exceeding reference data, thermal conductivity as temperature increases, and a simple production method thereof. The result is achieved in that pores of between 1 and 5 microns in size are distributed along the perimeters of grains in the micro-structure of each metal cluster in a nuclear fuel pellet, and in that located within the grains are pores which are predominantly nano-sized. In addition, the metal clusters comprise between 0.01 and 1.0 percent by mass.

Abstract: The invention relates to nuclear physics, and specifically to reactor fuel elements and units thereof, and particularly to the composition of solid ceramic fuel elements based on uranium dioxide, intended for and exhibiting characteristics for being used in variously-purposed nuclear reactors. The result consists in a more reliable, special structure and a simple composition of uranium dioxide without heterogeneous fuel pellet additives, approaching the characteristics of a monocrystal having enhanced, and specifically exceeding reference data, thermal conductivity as temperature increases, and a simple production method thereof. The result is achieved in that pores of between 1 and 5 microns in size are distributed along the perimeters of grains in the micro-structure of each metal cluster in a nuclear fuel pellet, and in that located within the grains are pores which are predominantly nano-sized. In addition, the metal clusters comprise between 0.01 and 1.0 percent by mass.

Abstract: The invention relates to the field of nuclear engineering and can be used in the manufacture of fuel rods and fuel assemblies for heavy liquid metal cooled reactors, and also in the manufacture of fuel rod simulators for use in irradiation devices designed to test the operability of real fuel assemblies. The present gadding of a fuel rod for a heavy liquid metal cooled reactor is in the form of a weldless tubular element h helically-coiled fins disposed on the outer surface of said element, which is made from a ferritic-martensitic chromium-silicon steel with a minimum ferrite grain size of 7 on the GOST 5639 scale, wherein each fin has an opening angle of from 22 to 40 (preferably from 30 to 40) and the cross-section of the fin is in the shape of a trapezoid with rounded corners at the top of the trapezoid and smooth corners at the base of the trapezoid. Also disclosed are a fuel rod comprising the above cladding, and a fuel assembly.