Non-metal seals, namely, flexible graphite seals for use as replacements for elastomer o-rings in high and low temperatures applications, in highly corrosive fluid applications, and in radioactive environments, for steam generators and heat-exchangers in nuclear applications, for ships and submarines, for valves, autoclaves, piping, heat exchangers, corrosive circuits, cryogenics, heat-transfer fluid, and high-and low-pressure steam applications in the chemical and petrochemical industries, f...