Accession Number : AD0479561


Title :   A NOVEL FORM OF THERMAL BARRIER FOR COMMUNICATIONS CABLES,


Corporate Author : DOW CHEMICAL CO MIDLAND MI


Personal Author(s) : Clock, G E ; Mildner, R C ; Walters, H A ; Woodland, P C


Report Date : Dec 1965


Pagination or Media Count : 27


Abstract : The development and testing of a new and economical form of thermal barrier, which has thermal characteristics superior to those of core wraps currently in use, is described. In one recommended form, it comprises a foamable coating adherent to one side of the metal tape which is used as the cable shield. The coating may either be prefoamed immediately prior to jacketing by the use of external heat or be caused to foam by the heat of the extruded jacket itself. A laboratory test technique has been developed to estimate the core and shield temperatures generated during the jacketing process, and comparison is made with the temperatures calculated theoretically. The results of comparative tests, based on this laboratory technique are tabulated for all the common forms of thermal barrier proposed for use in communications cable. Reference is made to factory trials utilizing this form of barrier in a jacketed cable construction. These trials confirm the beneficial effect of the high thermal resistance and low thermal capacitance of the new thermal barrier. (Author)


Descriptors :   *PLASTIC COATINGS , *ELECTRIC CABLES , *THERMAL INSULATION , *PROTECTIVE COVERINGS , TAPES , TEMPERATURE , DAMAGE , LIGHTNING , SHOCK RESISTANCE , POLYETHYLENE PLASTICS , LAMINATES , ELECTRICAL INSULATION , HEAT TRANSFER , ISOCYANATES , HALOCARBON PLASTICS , EXPANDED PLASTICS


Subject Categories : Electrical and Electronic Equipment


Distribution Statement : APPROVED FOR PUBLIC RELEASE