Rigid polyvinyl chloride pipe fitting filled with superfine activated calcium carbonate and preparation method thereof

The invention provides a rigid polyvinyl chloride pipe fitting filled with the superfine active calcium carbonate and a preparation method thereof, the superfine active calcium carbonate is used for replacing common light calcium carbonate to serve as filler, the dosage of other auxiliary components is reduced under the condition that the filling parts are kept unchanged, the product quality is improved, and the formula cost is reduced. The mixture subjected to hot mixing needs to be slowly stirred for several minutes in the hot mixing equipment from high speed to low speed, and then is discharged into the cold mixing equipment for cold mixing, so that the phenomenon of insufficient injection in the production process of the product can be effectively avoided; mixed powder is firstly subjected to melt extrusion through an extruder and then is fed into an injection molding machine for injection molding production, so that cold spots of products can be reduced; the temperature of the extruding machine barrel of