A method for the manufacture of a static mixer in an injection molding process includes the steps: injecting a polymer melt containing a foaming agent into a passage at an injection point at an injection pressure of less than 500 bar; filling the passage with the polymer melt containing a foaming agent; at least partial foaming of the melt containing a foaming agent in the passage, with the ratio of flow path length to height amounting to at least 10. The installation body is made up at least partly of foamed plastic and has a ratio of longitudinal dimension to diameter larger than 1 and a ratio of longitudinal dimension to wall thickness of at least 10.
1. A static mixer comprising
a tubular housing having a longitudinal axis and defining a flow passage for a fluid; and
at least two installation bodies disposed in said tubular housing and connected together in coaxial relation to each other disposed in said for mixing the fluid passing through said flow passage of said housing, each said installation body being rotated relative to the other of said two installation bodies and being comprised of at least partially foamed plastic having a longitudinal dimension, a width and a wall thickness wherein the ratio of said longitudinal dimension to said width is at least 1; and wherein the ratio of said longitudinal dimension to said wall thickness is at least 10.
2. A static mixer in accordance with claim 1 wherein at least one of said installation bodies has a longitudinal axis aligned in the direction of said longitudinal axis of said housing and said one installation body spans said housing to define a mixing space having a cross-sectional flow area in a plane normal to said longitudinal axis of said one installation body, said one installation body having at least one wall element for the division and/or deflection of the fluid flow into a direction deviating from the longitudinal direction;
and wherein a cross-sectional area formed by an intersection of said wall element with said plane amounts to a maximum of ⅕ of the cross-sectional flow area of said mixing space.
3. A static mixer in accordance with claim 2 wherein said wall element divides said mixing space into two part regions.
4. A static mixer in accordance with claim 2 wherein said installation body has a plurality of said wall elements wherein three wall elements of said plurality of wall elements are angularly disposed relative to said axis of said installation body and two wall elements of said plurality of wall elements are parallel to said axis of said installation body.
5. A static mixer in accordance with claim 2 wherein said wall element is spiral shaped and wherein said cross-sectional area formed by an intersection of said wall element with said plane is rotated relative to an opposite end of said wall element.
6. A static mixer in accordance with claim 2 wherein said wall element has a first broad side forming a flow-dividing edge and an oppositely disposed second broad side and wherein said one installation body further includes a deflection element integral with said second broad side of said wall element for the deflection of a flow from a first part region of said mixing space into a second part region of said mixing space.
7. A static mixer in accordance with claim 6 wherein a surface of said wall element bounded by said first and second broad sides and by longitudinal sides of said wall element is aligned substantially in the direction of said longitudinal axis of said one installation body.
8. A static mixer in accordance with claim 7 wherein said surface of said wall element is disposed in a transverse plane aligned at an angle to said longitudinal axis of said one installation body of from 45° to 90°.
9. A static mixer in accordance with claim 7 wherein said surface of said wall element is disposed in a transverse plane aligned at an angle to said longitudinal axis of said one installation body of from 60° to 90°.
10. A static mixer in accordance with claim 7 wherein said surface of said wall element is disposed in a transverse plane aligned at an angle to said longitudinal axis of said one installation body of from 75° to 90°.
11. A static mixer in accordance with claim 1 further comprising a plurality of connection elements extending longitudinally of said housing and connecting said at least two installation bodies together.