Abstract: A pressure vessel for use in production processes requiring elevating and ranging of temperatures and pressures during the process cycle, readily adaptable to production line operation, suitable for wafer processing in the semiconductor industry and for other industries and processes. The pressure vessel is configured within an open support frame with a stationary, preferably inverted, orientation. The cover or closing plate is vertically movable towards the mouth of the pressure vessel and functions as the platform by which the object under process is transferred into the vessel. The moving and locking mechanism for the cover is isolated and shielded from the process environment.