Method of cathodically protecting heat-insulated pipes

Claim 1

THE METHOD OF PROTECTING A METALLIC PIPE IN A HEAT DISTRIBUTION SYSTEM, WHICH IS ADAPTED TO CARRY A HEATED FLUID THERETHROUGH, FROM THE CORROSIVE DETERIORATING EFFECTS OF MOISTURE EXTERNALLY THEREOF WHICH CONSISTS OF (A) TELESCOPICALLY MOUNTING THE PIPE WITHIN A TUBULAR SHEATH OF WATER IMPERVIOUS MATERIAL; (B) SUBSTANTIALLY FILLING THE SPACE BETWEEN THE SHEATH AND THE PIPE WITH THERMALLY INSURLATING MATERIAL WHICH IS CHARACTERIZED BY HAVING GOOD DIELECTRIC PROPERTIES WHEN DRY BUT HAVING SOME ELECTRICAL CONDUCTING PROPERTIES WHEN WET; (C) MOUNTING ONE OR MORE ELECTRODES IN CONTACT WITH THE INSULATING MATERIAL IN THE SHEATH IN RADIALLY SPACED RELATION TO THE PIPE, AND OPERATIVELY DISTRIBUTED ALONG THE LENGTH OF THE PIPE, WITH MEANS ASSOCIATED THEREWITH FOR MAKING THE PIPE THE CATHODIC PORTION AND THE ELECTRODES THE ANODIC PORTION OF A CATHODIC PROTECTIVE SYSTEM; AND (D) CIRCULATING A HEATED FLUID THROUGH THE PIPE TO CAUSE MOISTURE WITHIN THE THERMALLY INSULATING MATERIAL SURROUNDING THE PIPE TO BE DRIVEN RADIALLY OUTWARDLY TOWARD THE SHEATH TO THEREBY OPEN-CIRCUIT THE CATHODIC PROTECTIVE SYSTEM. WHEREBY WHEN THE HEAT DISTRIBUTION SYSTEM IS FIRST INSTALLED AND BEFORE THE CIRCULATION OF HEATED FLUID THERETHROUGH, AND WHEN CIRCULATION OF THE HEATED FLUID MAY BE SEASONALLY TERMINATED THEREBY CAUSING REDISTRIBUTION OF MOISTURE WITHIN THE THERMALLY INSULATING MATERIAL, AND WHEN MOISTURE MAY OTHERWISE REACH THE PROXIMITY OF SAID PIPE AS BY LEAKS IN THE TUBULAR SHEATH OR IN THE PIPE ITSELF, THE CATHODIC PROTECTIVE SYSTEM PROVIDES CONTINUAL PROTECTION FOR THE PIPE AGAINST CORROSION.

Claim 2

THE METHOD OF PROTECTING A METALLIC PIPE IN A HEAT DISTRIBUTION SYSTEM, WHICH IS ADAPTED TO CARRY A HEATED FLUID THERETHROUGH, FROM THE CORROSIVE DETERIORATING EFFECTS OF MOISTURE EXTERNALLY THEREOF WHICH CONSISTS OF (A) TELESCOPICALLY MOUNTING THE PIPE WITHIN A TUBULAR SHEATH OF WATER IMPERVIOUS MATERIAL; (B) SUBSTANTIALLY FILLING THE SPACE BETWEEN THE SHEATH AND THE PIPE WITH THERMALLY INSURLATING MATERIAL WHICH IS CHARACTERIZED BY HAVING GOOD DIELECTRIC PROPERTIES WHEN DRY BUT HAVING SOME ELECTRICAL CONDUCTING PROPERTIES WHEN WET; (C) MOUNTING ONE OR MORE ELECTRODES IN CONTACT WITH THE INSULATING MATERIAL IN THE SHEATH IN RADIALLY SPACED RELATION TO THE PIPE, AND OPERATIVELY DISTRIBUTED ALONG THE LENGTH OF THE PIPE, WITH MEANS ASSOCIATED THEREWITH FOR MAKING THE PIPE THE CATHODIC PORTION AND THE ELECTRODES THE ANODIC PORTION OF A CATHODIC PROTECTIVE SYSTEM; AND (D) CIRCULATING A HEATED FLUID THROUGH THE PIPE TO CAUSE MOISTURE WITHIN THE THERMALLY INSULATING MATERIAL SURROUNDING THE PIPE TO BE DRIVEN RADIALLY OUTWARDLY TOWARD THE SHEATH TO THEREBY OPEN-CIRCUIT THE CATHODIC PROTECTIVE SYSTEM. WHEREBY WHEN THE HEAT DISTRIBUTION SYSTEM IS FIRST INSTALLED AND BEFORE THE CIRCULATION OF HEATED FLUID THERETHROUGH, AND WHEN CIRCULATION OF THE HEATED FLUID MAY BE SEASONALLY TERMINATED THEREBY CAUSING REDISTRIBUTION OF MOISTURE WITHIN THE THERMALLY INSULATING MATERIAL, AND WHEN MOISTURE MAY OTHERWISE REACH THE PROXIMITY OF SAID PIPE AS BY LEAKS IN THE TUBULAR SHEATH OR IN THE PIPE ITSELF, THE CATHODIC PROTECTIVE SYSTEM PROVIDES CONTINUAL PROTECTION FOR THE PIPE AGAINST CORROSION.