GB983559A - Improvements relating to safety devices for doors or covers for pressure vessels - Google Patents

Abstract

983,559. Pressure-resisting doors. LEEDS & BRADFORD BOILER CO. Ltd., and H. M. H. PICKARD. Aug. 6, 1963 [Aug. 15, 1962], No. 31303/62. Heading F2P. A pressure vessel such as a kier, autoclave, tank, retort, vulcanizing pan has a safety device for arresting a forced quick opening of the door beyond a predetermined position when the door is unlocked. The device comprises a pivoted catch 2 mounted on the mouth ring 5 of the vessel and formed with a slot 6 in which can engage a stop 8 provided on an adjacent part of the door when the door is closed, the slot being formed between the ends thereof with a mouth 7 through which the stop can pass to permit complete opening of the door. The arrangement is such that when a pressure does not exist within the vessel sufficient to effect quick opening of the door, the stop coacts with the slot at one side 10 of the mouth thereof and swings the catch slowly about the pivot 3, up and down, permitting the stop to pass through the mouth of the slot and out of engagement with the catch to allow complete opening of the door, but that when a pressure exists within the vessel sufficient to effect quick opening of the door when the latter is unlocked, the influence of this pressure on the door tending to force it open quickly, results in a rapid and forceful swinging movement being imparted to the catch by the stop, whereby the catch is swung and the stop moves so quickly that the stop is unable to pass through the mouth of the catch, and the part of the slot 6b at the other side of the mouth engages the stop and so arrests further opening of the door. As shown, an arm 11 is formed so as to control the centre of gravity of the catch in relation to the axis 3, and the catch has a pressure-applying pad 12 which enables pressure to be exerted on the door sufficient to overcome the springiness of a sealing gasket between the mouth of the vessel and the door.