GB847606A - Improvements relating to doors or covers for pressure vessels - Google Patents

Abstract

847,606. Doors for resisting fluid pressure. LEEDS & BRADFORD BOILER CO. Ltd., and PICKARD, H. M. H. May 8, 1957 [May 9, 1956], No. 14397/56. Class 123(1) Quick-opening doors for pressure vessels of the form described in Specifications 412,700 and 667,929, wherein the door 1 is held to its seating by a series of pivoted latches mounted in a keep ring 2 and which by rotation of an operating ring 3 may be simultaneously moved into and out of the locking position, are prevented from opening fully when the latches are unlocked to reduce the risk to the operator if a pressure remains in the vessel by a trigger 4 comprising two arms 8, 9 pivotally mounted on a bolt 5 on the front of the ring 2. When the operating ring 3 begins to be rotated to the door-closing position the arm 8 is clear of the door 1 while the outer arm 9 is engaged by a lug 10 on the ring to swing the arm 8 into the position shown, in which it obstructs the door 1. When the ring is moved to the door-opening position the trigger which remains in position prevents the door from opening more than a small distance so that any pressure in the vessel is released without danger. The trigger can then be swung clear of the door by a handle 12 and the door fully opened. A cam surface 13 is provided on the back of the trigger to enable the closing door to move the trigger clear of the opening without damage to the seal.