METHOD OF SEALING NUCLEAR REACTOR FUEL ELEMENTS Russian patent published in 2009 - IPC B23K11/02 B23K11/10 B23K31/02 G21C3/10 G21C21/00 

FIELD: welding works.

SUBSTANCE: present invention pertains to welding, particularly to the method of sealing fuel elements of a nuclear reactor using contact-butt welding. Contact-butt welding is done on a fuel element casing with an end-cap, with maximum diametre less than the outer diametre of the casing, and greater than its inner diametre. The end of the casing is put into an expanding mounting with a depression. Welding is done with rate of increase of welding current to maximum value in the initial welding moment in the range of 1-3 kA/ms and its density in that period from 1.5 to 2.5 kA/mm² with specific pressure of 35-80 kg/mm² for a period of 10-60 ms. The end cap is moved deep into the casing at a distance of 2-5 times the thickness of the wall of the casing. If necessary, the displacement of the end cap can be limited due to restriction of the movement of the electrode linked to the actuator of the welding force of the installation.

EFFECT: invention can be used in nuclear power engineering.

2 cl, 9 dwg, 1 ex