| 摘要 |
894,418. Reactors; handling fuel elements. ALLMANNA SVENSKA ELEKTRISKA A.B. March 1, 1960. [March 4, 1959], No. 7175/60. Class 39(4) A gas-cooled reactor 1 has a number of sockets 19 in its cover 4 normally sealed by plugs 20 to which fuel elements 21 are attached by bolts 22. A water tank 5 covers the reactor 1 and two chambers 7, 8, the chambers being defined by the reactor shielding 3, a wall 9 and a partition 10. Gates 11 in the wall 9 connect the chambers 7, 8 with further chambers 12, 13, the chambers 7, 12 being filled with water to a level above the height of the gate. To refuel the reactor a charging machine 17 is moved above the selected socket 19, the machine having a pressure vessel which is pressurized at the reactor gas pressure. The lower end 25 of the machine is screwed on to the socket 19 and a slide valve 31 is opened. A key 28 is lowered into a hexagonal cavity 23 of the plug 20 and rotated whereby the plug may be unscrewed. Pawls 30 in the key are moved outwards to engage an annular slot 24 so that the plug together with the fuel elements. may be hoisted into the machine 17. New fuel elements and a plug which have been previously stowed in the machine are then lowered and the plug screwed into position. The valve 31 is closed and the machine 17 moved above a socket 15 to which it is screwed. A valve 16 in the socket 15 is opened and the spent fuel elements are lowered into a container 14, the container then being lowered and moved through the gate 11 into the chamber 12. New fuel elements are introduced into the machine through the chambers 13, 8, the machine being screwed to a socket 15<SP>1</SP> having a valve, this socket being situated in the floor of the tank 5 above the chamber 8. The new fuel elements are manually attached to the key 28. |
