| 摘要 |
<p>1,106,455. Gas locks. UNITED KINGDOM ATOMIC ENERGY AUTHORITY. 3 June, 1965 [10 June, 1964], No. 24012/64. Heading F2P. A gas lock between the discharge end 13 of a furnace used for treating toxic, radioactive material and the interior of hood 32 which can be evacuated or purged at 40 comprises a composite rim member 25, 26 defining and opening 29, a closure member for closing said opening, first sealing means which includes an 0-ring 23 in the grooved rim member 25 co-operating with the face 26 of the closure member to form a primary gas seal when jack 17 is actuated, and secondary back-up sealing means formed by surfaces 21 and 30 which co-operate to form a subsidiary pressure seal when ring 25 is removed with the jack extended for replacement of the O-ring. In normal operation, a boat 51 containing radio-active material is pushed by a ram (not shown) on to a table 45 which is slidably mounted on rails 44 attached to the top of the closure member. Ram 17 is actuated to raise the closure member until its face 20 seats against the O-ring, guides 12, flexible connection 18 and closure spigot portion 22 ensuring correct alignment of the closure member. A pivoted link 49 also centralizes the table. The interior of the hood may then be increased to atmospheric pressure, the hood raised by a further jack 35, and the boat removed. If replacement of the 0-ring 23 is necessary, the ram 17 is maintained extended and the screws 27 uniformly unscrewed. The ring 25 is unseated by the upwards pressure of the jack and the secondary sealing surfaces cooperate to form a subsidiary pressure barrier until the 0-ring is replaced. 'This arrangement permits the primary seal to be replaced whilst maintaining the furnace outlet isolated from atmosphere. The 0-ring 23 may be alternatively disposed in a groove in the closure member face 20. Further 0-rings 28 and 38 seal the composite ring members and hood respectively.</p> |
