Kernreaktor

摘要

1,139,406. Reactors. UNITED KINGDOM ATOMIC ENERGY AUTHORITY. 4 Oct., 1967 [14 Oct., 1966; 25 Nov., 1966; 13 Jan., 1967; 15 March, 1967; 21 June, 1967; 12 July, 1967]. Nos. 12167/67; 2048/67; 28744/67; 32085/67, 46157/66 and 52997/66. Heading G6C. In a marine, pressurized water, integral reactor, the heat exchangers are supported from an annular ring member, forming part of the pressure vessel, and mounted and sealed between the upper and lower parts of the vessel. The exchanger inlet and outlet tubes pass through the annular member together with the control rod driving shafts. Pressurization is effected by electric heating of the water free surface, to inhibit boiling. The pressure vessel is lined internally with stainless steel and thermal insulation. The coolant circulators are mounted on the pressure vessel upper member. The annular ring also supports the core and the latter rests at the base of a vertical tubular member, the upper rim of which is flanged and is carried on an internal shoulder in the ring member. The pressure vessel can be constructed of segments, held together by prestressed tendons. The pressure vessel may be enclosed in a caisson submerged in neutron absorbing liquid which will reduce nuclear activity in the event of a pressure vessel failure. In one embodiment, Fig. 5, the annular ring 13 is clamped between the top closure 30 and the body 11 of the pressure vessel enclosing the fuel assemblies 19. The ring carries the core support 15 on the shoulder 4, and the heat exchanger 13a, and is penetrated by inlets and outlets 79 for the secondary coolant. The control element operating rods 95 are positioned by the rotary shafts 96 penetrating the ring 13. The electric heater 103 evaporates water entering the tube 104 and generates a vapour pressure, thus inhibiting boiling in the reactor core. The spray ring 108 directs cold water into the pressure vessel and may be used to reduce vapour pressure.