RAPTURE PROTECTION INSTALLATION FOR PRESSURE CAMERAS IN NUCLEAR REACTOR INSTALLATIONS, OVERALL FOR REACTOR PRESSURE CAMERAS

摘要

The pressure vessel closure head (3) is clamped in a sealing fashion with its closure head flange (3.1) by means of prestressed expansion bolts (4) having nuts (4.2) and washers (U1) against the counter-flange (2.1) of a pressure vessel opening. In this arrangement, the washers (U1) are constructed as deformation members and are dimensioned to match the expansion bolts (4) in such a way that upon overshooting of a limiting internal pressure they give way to the closure head forces, under plastic deformation, by the distance DELTA lü in the pressing-on direction. The reduction in the overpressure takes place via the closure head sealing gap (5) which gapes correspondingly by an axial gap of DELTA lü, as far as a value at which the prestressing force of the bolts (4) remaining in the elastic range is sufficient to reseal the pressure vessel (1). IMAGE