Pressure vessels having thermal insulsation

Claim 1

A NUCLEAR REACTOR PRESSURE VESSEL HAVING AN INNER WALL AND A THERMAL BARRIER SYSTEM ON THE INNER WALL, THE THERMAL BARRIER SYSTEM INCLUDING A METAL LINER COEXTENSIVE WITH AND APPLIED TO THE INNER WALL OF THE VESSEL, AN IMPERVIOUS METAL MEMBRANE SPACED FROM SAID LINER IN SUBSTANTIALLY PARALLEL RELATIONSHIP THERETO, HEAT-RESISTANT INSULATION CONTAINED IN THE SPACE BETWEEN THE LINER AND THE MEMBRANE, TUBULAR STUDS SECURED TO THE MEMBRANE AND LINER WHEREBY THE MEMBRANE COMPRESSES THE HEAT-RESISTANT INSULATION TO THE LINER, SAID MEMBRANE HAVING FLEXIBLE CORRUGATED PORTIONS, SAID FLEXIBLE CORRUGATED PORTIONS BEING OF LESSER CROSS SECTION THAN THE CROSS SECTION OF THE MAJOR PORTION OF SAID MEMBRANE, EACH OF SAID STUDS COMPRISING A HOLLOW BODY HAVING AN INNER END AND A MOUTH LOCATED EXTERIORLY OF THE MEMBRANE, AN IMPACT COLLAR SURROUNDING SAID HOLLOW BODY, SAID COLLAR BEING OF SUCH LENGTH AS TO EXTEND INTO THE SPACE BETWEEN THE LINER AND MEMBRANE AND TERMINATE ADJACENT THE MOUTH OF THE HOLLOW BODY, SAID COLLAR HAVING PASSAGES EXTENDING AXIALLY THERETHROUGH TO PROVIDE FLUID COMMUNICATION BETWEEN THE INSULATION AND THE INTERIOR OF THE HOLLOW BODY, MEANS WITHIN THE SPACE ADJACENT THE INNER END OF THE COLLAR FOR PREVENTING EGRESS OF THE INSULATION, AND A CAP ATTACHED TO THE COLLAR WHEREBY THERE IS PROVIDED A TORTUOUS EXTENSION OF SAID PASSAGES FOR PROVIDING MAXIMUM ATTENUATION OF HIGH-SOUND PRESSURE LEVELS PREVAILING WITHIN THE REACTOR AND AVOIDING ACOUSTIC DAMAGE TO THE INSULATION.