Synthetic resins as applied to large rotating apparatus

The philosophy governing high voltage synthetic resin bonded insulation has been clearly defined. This concept is predicated on the use of solventless polymers processed by vacuum-pressure impregnation techniques. These essential requirements narrow the selection of applicable polymers to but three prime choices; unsaturated polyesters, epoxies and vinyl silicones. It is to be understood that many modifications of these three basic resins do exist but the classification of such materials remains the same. Since vinyl silicones are not of interest at this time, the discussion will be devoted to only the unsaturated polyester resins and the epoxy resins.