Perfectionnements apportés aux moyens de liaison étanche entre diverses structures, notamment pour la commande des barres de contrôle d'un réacteur nucléaire

936,903. Controlling reactors. COMMISSARIAT A L'ENERGIE ATOMIQUE. March 30, 1962 [April 10, 1961], No. 12421/62. Class 39 (4). The nuclear reactor control-rod 3 is manipulated inside the pressure vessel 1 by the winding device 13 mounted on the biological shield 2. The flexible sealing tube 15, 16 allows relative displacement between the shield and the vessel due to thermal dimension changes and creep and provides a fluid-tight coupling. The tubes 15, 16 are welded to the tank 1, project through the shield 2 and are sealed at the upper end by the cover 20. The projection 9 of the plug 5 passes slidably through 20 to engage the cap 10 secured to the shield upper surface. The guide tube 4 and the plug 5 are flexibly connected at the knuckle joint 6 and axial expansion may take place with a sliding action between 9 and 20. A partial balance of the weight is effected by the spring 27 and this, together with the flexibility of 15, 16 reduces the shearing stresses at the neck 17.