Paper Cable Saturants: European Preferences and Selection

A significant and interesting difference between American and European practice in the manufacture of mass-impregnated paper-insulated cables for low and medium voltage is that, while in Europe oil-rosin compounds are widely used as the saturant, in the United States straight oils or hydrocarbon blends with oils find the widest application, and rosin compounds are not favored. The author considers this difference in techniques to be of sufficient interest to warrant investigation, and the European viewpoint supporting the use of oil and rosin blends is presented in this paper. In recent years wax-bearing compounds have been developed for the mass impregnation of cables required to be nondraining in service. These cables are finding ever-increasing markets for voltages up to 11 kv. Oilostatic cables, which are favored in the United States, are not widely used in Europe for operation at the higher voltages, for which hollow-core or gas pressure designs are preferred. The characteristics of oils for these applications are discussed. Much of the material supports and corroborates the work of previous investigators (see the list of references).