Abstract: A plasma torch includes a distal part (4) immersed in a container (43) to be decontaminated. A plasma jet (44) produced by sudden discharge of a capacitor between main electrodes (9,11) sweeps directly or by reflection or by sweep-over the whole internal surface of the container (43). The gas exhaust is preferably controlled by a valve (47) operating by gravity on the orifice (42) of the container. The torch is useful for intense decontamination, in particular at a high rate, using an extremely brief and intense plasma flash.

Abstract: Process and apparatus for the alignment of a laser beam by optical sighting means and process for using the apparatus for checking the alignment.The invention consists of preferably carrying out a sighting of the emergence or starting point of the laser beam illuminated for this purpose by means of a sight tube and beam splitting means and using the displacements of the sight tube-splitting means assembly with respect to the laser, then immobilizing the assembly with respect to the support plate carrying the laser and then performing a sighting of the target illuminated for this purpose by using the movements of the support plate and/or a laser beam orienting mirror. The alignment is checked during the operation of the laser by replacing the splitting means by a ring mirror and by observing the target.Application to laser machining in a blind enclosure.

Abstract: The present invention relates to a device for controlling the dimensions and spaced-apart relationship of rigid pieces disposed in a bundle. Said device comprises: two supple probes adapted to transmit a light beam and insertable between rows of pieces so as to surround one of these rows; means for positioning and displacing these probes; a source of light emitting a light beam transmitted by the first probe then picked up by the second transmitting it to a photodetector producing an electrical signal; electronic means for processing this signal, furnishing information making it possible to control, from reference values, the dimensions and spaced apart relationship of the pieces, due to the modulation of said signal, provoked by the successive occultations of the light beam by the pieces, during the displacement of the probes along the row of pieces. The invention is applicable to the control of the pencils of a fuel assembly of a nuclear reactor.