| 摘要 |
1,090,824. Controlling reactors. ATOMENERGI A.B. Dec. 8, 1964 [Dec. 20, 1963], No. 49938/64. Heading G6C. Shutdown and / or reactivity control, in a reactor having forced coolant circulation, is achieved by means of a neutron absorbing body in a tube passing through the core, the position which the body adopts being determined by coolant flow conditions; the tube is open at its lower end, the upper end being at a point in the reactor at lower coolant pressure and the lower end at a point of higher pressure, so that under normal coolant flow the body is situated in the tube above the core, but when coolant flow is reduced, the body sinks to a position in the tube within the core. Fig. 1 shows the reactor 1 combined with a heat exchanger 7, there being a roller bearing 21 between them to permit lateral movement. Water coolant passes from pump 11 through the core (dotted) within a tube 14 and thence through the heat exchanger within U-tubes 10, downwards through the outer core zone to the pump 11. The neutron absorbing bodies 32 are boron steel or silver-cadmium-indium alloy spheres, and their containing tubes 30 are of zircalloy; alternatively they may be of cylindrical shape. The invention is also applicable to gas cooled reactors. In Fig. 2 (not shown), the tubes 30 pass to the low pressure zone of the coolant circuit via a control valve, by means of which the reactor may be shut down, or power control achieved, by varying the position adapted by the train of spheres 30; the train, when withdrawn, from the core extends into a closed end pipe beyond the point at which coolant leaves the pipe 30. Reference has been directed by the Comptroller to Specification 969,089. |
