ROSS CONE SCREW VERTICAL BLENDER MIXES POLYMER CONCRETE FOR ELECTRICAL INSULATORS
A division of a major polyester resin supplier developed superior polymer concretes for electrical insulator applications. The polymer concrete used for electrical insulators are based on polyester resin chemistry and are filled with alumina trihydrate (ATH) for arc and track resistance and fused silica for reducing the coefficient of thermal expansion of the insulators. A Ross 60 cu.ft. Vertical Blender was selected to produce this product and was mounted to a special mezzanine. Load cells helped control the charging of raw materials, by weight, directly into the blender. The jacketed cone is warmed to lower the viscosity of the resin. This allows easier wet-out of the solids and a higher ultimate solids loading than with a cold resin. When the batch is complete, a pneumatically operated gate valve is opened and the 30,000 to 50,000 cps polymer concrete is discharged under a positive internal pressure of 23 psig. The polymer concrete is pumped out of the blender and into a motionless (static) mixer where the catalyst is added continuously. The catalyzed mixture is then cast into insulator molds.