FUEL ELEMENTS, METHOD OF MANUFACTURE OF FUEL ELEMENTS AND DEVICE FOR ITS EMBODIMENT

The proposed element can be used in nuclear technology, specifically in the construction of fuel elements and the associated production technology. The aim of the inventions is to increase the structural strength and corrosion resistance of fuel elements. The fuel element comprises an outer jacket (1) filled with nuclear fuel and plugs (2) welded into it down to a certain depth; in the weld zone, a region (3) is created in which the structure of the metal is altered down to a depth equal to the depth of the plug (2), namely (2-5) delta , and of a width from the inner surface of the jacket (1) not exceeding 0.9 delta , delta being the width of the jacket wall thickness. The proposed method involves manufacturing the plug (1) with an outer diameter which is (0.2 - 1.4) delta greater than the inner diameter, delta being the jacket wall thickness, fixing the jacket (1) in a current supply element (4) at a certain depth, compressing the jacket (1) and plug (2) and heating the welded parts with an electrical current which is distributed over the current supply element (4) and jacket (1) in such a way that the current flowing in the jacket section extending (2.0 - 5) delta from the end face is equal to between 0.3 and 0.9 times the welding current, while also ensuring that heat is carried away from the outer surface of the jacket (1). The proposed device comprises an annular current supply element (4) part of which is in contact with the end face region and made from an assembly of electrically insulating plates (5) interconnected by an electrical shunt, the relative proportions of the components being as follows: each plate (5) has a thickness equal to (0.2 - 2) delta , delta being the jacket wall thickness and the size of the assembly element of the current supply element (4) along the axis of its aperture has a length equal to 2.5 - 6 delta . The result is improved structural strength and corrosion resistance of the fuel elements.