Abstract: A safety latch mechanism for use in connection with a pressure vessel of the type having a shell, a closure for removably closing an access opening defined by the shell and a locking ring rotatably supported by the shell adjacent the access opening for releasably locking the closure in access opening closed position. The mechanism features a first latch member mounted by the shell for releaseably preventing unlocking rotation of the locking ring relative to the shell and a second latch member mounted by the locking ring and responsive to movement of the first member for releasably preventing relative rotational movements of the locking ring and closure. The first member is operatively associated with a vessel exhaust valve, which tends to constrain unlatching movements of the first and second latch members, when the pressure within the vessel exceeds a safe level at which the closure may be operated without the possibility of injury to person or property.

Abstract: A fluid operated cylinder device particularly adapted to lift a load relative to a load support includes a hollow casing having a closed end for attachment to the load support; an elongated rigid rod extending lengthwise of the casing and having a first end arranged within the casing and rigidly fixed to its closed end and a second end disposed outwardly of the casing for attachment to the load support; at least one open ended fluid operated cylinder arranged intermediate the casing and rod for sliding movements lengthwise thereof, such cylinder having an outer end disposed outwardly of the casing for attachment to the load; and fluid means for introducing and withdrawing fluid from the casing for effecting sliding movements of the cylinder and lifting and lowering of the load. Single and double acting embodiments of the cylinder device are disclosed.

Abstract: An improved mechanism is disclosed for use in mounting a door on a pressure vessel for opening and closing movements in a manner permitting minimum clearing distances to be maintained between obstructions and the front or sides of such vessel.