Image Number 6 for United States Patent #5204065.
A high temperature, high pressure chemical digestion vessel comprising an inner container within which digestion is to take place under high temperature and high pressure conditions. The container is provided with a vent. A replaceable, rupturable pressure release disk is provided having a predetermined rupture pressure for being sealingly interposed in covering relation to the vent to seal the container and thereby enclose a substance to be digested in the container. The disk ruptures and releases pressure within the container if pressure within the container reaches the predetermined rupture pressure. The pressure release disk comprises a flat sheet material. A seal cap is provided for holding the pressure release disk in sealing relation to the vent in the container. An outer pressure resisting-casement is provided for receiving the container therein and providing support to the container. In one embodiment, a pressure chamber is defined between the seal cap and the pressure release disk to transmit pressure information to a pressure sensor exterior to the vessel and to isolate a test sample from the exterior of the vessel.