| 摘要 |
1,109,925. Reactors. SOCIETE ANGLOBELGE VULCAIN S.A. 2 Dec., 1965 [4 Dec., 1964], No. 51163/65. Heading G6C. A pressurized water comprises a pressure vessel containing a core and a pressurizer, the fuel elements forming the core being suspended from the bottom plate of the pressurizer. A pres. sure fluid, for instance a gas or a vapour, is confined in the pressurizer so as to transmit its pressure to the coolant water. The pressurizer has the form of a cylindrical vessel having its bottom plate formed of two spaced plates 6, 7 with aligned openings for supporting cluster-type fuel elements 3, each of the openings in the upper plate 6 having a tapered portion 10. The sleeve 13 of each fuel element 3 is fixed to a support member 15 by means of ribs 14 (only one of which is shown). The support member 15 belongs to a latch mechanism by means of which the fuel element 3 is suspended from the plate 6 of the pressurizer. Each latch mechanism has a movable member in the form of a tapered plug 16 having an externally screw-threaded shank 17 to engage an internally screw-threaded upper end cap 18 of the support member 15 and an internally screw-threaded lower end cap 19 of an intermediate deformable thimble 20 having three circumferentially equi-spaced, longitudinally extending slots 21 (only one of which is shown). The support member 15 has a hollow cylindrical shape having openings 25, an external locating flange 26 with a slot 27 intended to receive a pin 28 carried by the plate 7, and a lower end cap 29 having a spray nozzle 30. During the assembly of the core, the fuel elements 3 are inserted to bear upon a bottom core locating plate (not shown) and the pressurizer is then placed in position. Jaws 31 of a remote handling tool are employed for seizing each head 22 of the plugs 16 in turn and raising the fuel elements 3 until the locating flanges 26 abut the underside of the plate 7, after which the jaws 31 are rotated to cause the plugs 16 to enter and deform the thimbles 20, thus latching the fuel elements 3 to the plate 6. In this position the shanks 17 are freed from the caps 19, thus simplifying the removal of the plugs 16 for refuelling operations, during which operations the manifold 35 between the plates 6,7 receives an auxiliary coolant which passes through the openings 25 and the nozzles 30 to spray over the fuel elements 3. |
