Material Temperature VariationAmbient TemperaturePolymer Viscosity VariationRam Pressure VariationOil Temperature VariationVariation in Length of Time of Oil Injection/ram up timeCarbon Black Hardness VariationMoisture in Raw materials or SlabVariations in Loading Time, Carbon Black Charge time, Slab/Polymer Throat JamsVariations in Loading Techniques (Polymer placement, Bag placement, spread & stacking of slab etc.