Sealed Cable Inlet through an External and an Internal Wall of a Containment Shell of a Nuclear Power Station

摘要

The invention relates to the field of electrical engineering, and specifically to sealed inlets of electrical circuits into a sealed area of a multi-layered containment shell of a nuclear power station. This design can be used in passages through an external and an internal wall which are subject to relative mutual displacement as a consequence of a seismic phenomenon or thermal expansion of the walls and passage. The problem addressed by the present invention is that of increasing the operating reliability of a sealed cable inlet when high-voltage electrical conductors which have little bending capacity are used. The problem addressed is achieved in that the sealed cable inlet through an external and an internal wall of a containment shell of a nuclear power station comprises an embedded pipe (3) which is arranged in the internal wall (1), with an inlet section (44) of a cable (2) fixed rigidly within said pipe. A means for compensating for a relative movement between the cable (2) and the external wall (11) is mounted in the external wall (11) coaxially with respect to the pipe (3). The compensating means has a tube (19) with a bellows (24) on the external end plane (20) and with a second analogous bellows (25) which is mounted symmetrically on the opposite end plane (21) of the tube (19) at the internal surface (18) of the external wall (11). The free ends (30) and (31) of the two bellows (24) and (25) are of conical design and have internal surfaces (28) and (29) which are support elements for an outlet section (46) of the cable (2), which is arranged freely in the tube (19) with a gap (47) relative to the internal surface (49) of the tube (19). The gap (47) between the braiding (48) along the external surface of the cable (2) and the internal surface (49) of the tube (19) is selected using a design calculation. The gap (47) must not be less than the value of maximum orthogonal thermo-seismic movement in one plane of the internal wall (1) relative to the external wall (11) and change in the coaxial position of the cable (2) in the tube (19).