Apparatus for injecting additives into a flow of a highly viscous liquid

A method for injecting and admixing at least one additive into a product flow formed by a highly viscous liquid in a tube section having at least one aperture, the tube section including therein at least one wall section spaced from an inner surface of the tube section and oriented in the direction of the product flow in the tube section, the at least one wall section having at least one bore and having a flat inward facing surface defining a plane disposed closer to a center of the tube section than an outward facing surface, at least one supply member each extending through one of the at least one aperture for injecting the at least one additive, each of the at least one supply member having a discharge opening coupled to one of the at least one bore of the at least one wall section, wherein said discharge opening lies on said plane, the method comprising the steps of:

• conducting the product flow on both the inward facing surface and the outward facing surface of the at least one wall section in the tube section;
• and
• injecting the at least one additive via the at least one supply member out the discharge opening through the at least one bore of the at least one wall section into the product flow transversely to the direction of the pro duct flow, the at least one additive spreading out downstream on the inward facing surface of the at least one wall section and forming a trail so as to be embedded into the product flow and pass homogeneously distributed into the product flow through diffusion, where in the highly viscous liquid comprises a polymer melt and the at least one additive comprises a lubricant.

A method for injecting and admixing at least one additive into a product flow formed by a highly viscous liquid in a tube section having a plurality of apertures, the tube section including therein a plurality of ring-shaped wall sections having different inner diameters and being arranged concentrically, the plurality of ring-shaped wall sections being spaced from an inner surface of the tube section and oriented in the direction of the product flow in the tube section, the plurality of ring-shaped wall sections including a first wall section lying closer to the center of the tube section arranged upstream of an adjacent wall section lying further from the center of the tube section than the first wall section, each of the plurality of ring-shaped wall sections having at least one bore and having an inward facing surface disposed closer to a center of the tube section than an outward facing surface, a plurality of supply members each extending through one of the plurality of apertures for injecting the at least one additive, each of the plurality of supply members having a discharge opening coupled to one of the at least one bore of the plurality of ring-shaped wall sections, the method comprising the steps of:

• conducting the product flow on both the inward facing surface and the outward facing surface of each of the plurality of ring-shaped wall sections in the tube section;
• and
• injecting the at least one additive via the plurality of supply members out the discharge openings
• through the at least one bore of each of the plurality of ring-shaped wall section into the product flow transversely to the direction of the product flow, the at least one additive spreading out downstream on the inward facing surface of each of the plurality of ring-shaped wall sections and forming a trail so as to be embedded into the product flow and pass homogeneously distributed into the product flow through diffusion.