Development of a Reduced Wall 138kV HPOF Pipe Type Cable and Joints for RE-Conductoring of Existing 69kV Lines on the Florida Power & Light Company System

A 138kV pipe type cable with 348 mils (8.8mm) of paper insulation and two types of joints have been developed for re-conductoring existing 69kV HPOF pipe type cable circuits installed in 6-5/8 inch (168mm) pipes on the Florida Power & Light Company system. A cost saving of 60 percent or $11.7 million will be realized in the re-conductoring of 15.9 miles (25.6km) of circuit compared to installation of new 138kV cables in 8-5/8 inch (219mm) pipe. Laboratory test data on cable as manufactured and on cable returned after one year in-service operation at the Florida Power & Light test site validate the adequacy of the optimized design.