Apparatus for applying covers to nuclear reactor vessels
AssigneesCompagnie des Aciers, Outillages et Equipements Industriels-le Roulement, Etat Francais
InventorsGeorges Boudet, Pierre Gibert
Life of this patent
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Abstract
Stud bolts are threaded into the body of a nuclear reactor vessel and tenned by exerting forces on tensioning nuts located on the upper end of the studs. While the studs are under tension, a cover is attached to the vessel by tightening nuts on the studs against the cover. The tensioning nuts are applied to the studs by immobilizing the studs axially and rotationally, and rotating the tensioning nuts with a pair of driven, diametrically opposed striking rollers. External threads on the striking rollers, external threads on the nut and internal threads on the nut all have the same pitch so that the threads on the striking roller remain engaged with the external threads on the nut as the nut moves axially while being threaded onto the immobilized stud.
Claims9
Apparatus for turning an externally and internally threaded tensioning nut on a stud used to attach the cover to a nuclear reactor tank, comprising, at least one striking roller engageable with the external circumference of the nut, means mounting said roller adjacent said nut and, roller drive means for rotating the striking roller to rotate the nut on the stud, said striking roller having its circumference provided with external threads which have the same profile as the external threads of the nut.
Dependencies are inferred from the claim text.