GB1253153A - - Google Patents

Abstract

1,253,153. Seals. COMMISSARIAT A L'ENERGIE ATOMIQUE. 7 Nov., 1969 [20 Nov., 1968], No. 54563/69. Heading F2B. [Also in Divisions G4-G6] A sealing device for a rotary plug 2 and a tank 1 of a nuclear reactor comprises a rigid support 18 which faces the surfaces of two parts to be sealed on each side of the line of separation or gap 16, at least four uniformly-spaced grooves containing inflatable seals 20a ... 20f and having a distance between their axes which is smaller than the width of each of the surfaces to be sealed, and means 23 for displacing the support between different positions including two end positions so that in each of the end positions leak-tightness is ensured with only some of the seals whilst the remaining seal or seals is or are freed from the surfaces and made accessible. As shown, six inflatable seals are provided and additional sealing is effected by fluid under pressure in the spaces between pairs of seals supplied through ducts 24. The plug 2 is rotatable in the tank 1 on bearings 10 and driven through gear teeth 8. The support 18 is raised or lowered by a driving device 23. To remove the three upper seals, jacks 14 are first lowered so that the plug flange 3 contacts the rim 4 of the tank, the support then being raised by the driving device 23 and secured in position by clamps (26), Fig. 2 (not shown); after removal of the flange 6 of the plug, the three upper seals, which may be deflated if necessary, are exposed. To remove the three lower seals, members (30), Fig. 3 (not shown) are fixed to the flange 6 to guide the support 18 before it is lowered by the driving device 23 to expose the three lower seals for replacement.