Method and apparatus for multi-stream metered extrusion
View Patent ↗An extrusion apparatus for extruding multiple streams of extrusion material as extruded end-products and in the coating of substrates. A flow joiner in an extrusion head combines multiple metered streams such as from a gear pump, into a uniform extrusion flow.
1. A method for coating a substrate comprising:
providing a plurality of metered, separate individual streams of coating material to an extrusion head;
receiving the plurality of metered, separate individual streams of coating material at a plurality of corresponding respective receiving regions of a flow joiner within the extrusion head;
expanding each of the plurality of metered, separate individual streams of coating material in a plurality of corresponding respective expansion regions of the flow joiner;
joining the expanded plurality of metered, separate individual streams from the plurality of corresponding respective expansion regions of the flow joiner into a coating flow at an annular space of the flow joiner, each of the plurality of corresponding respective expansion regions having a first end adjacent each of the plurality of corresponding respective receiving regions, each of the plurality of corresponding respective expansion regions having a second end adjacent the annular space, the second end being wider than the first end, the plurality of corresponding respective expansion regions each having a substantially triangular shape; and
extruding the coating flow on to a substrate.
2. The method of claim 1 , wherein the coating flow is an annular flow.
3. The method of claim 2 , wherein the substrate is cylindrical.
4. The method of claim 1 , wherein one or more individual streams include a color different from one or more other individual streams.
5. The method of claim 1 , wherein at least two individual streams each include a different coating material.
6. The method of claim 1 further comprising joining a second coating flow on a second tapered surface of the extrusion head, extruding the second coating flow on to an underlying coating flow and extruding multiple layers of coating on to the substrate.
7. The method of claim 1 , wherein the substrate is metal conductor core and the coating material is an insulation layer.
8. The method of claim 1 , further comprising pumping the individual streams of coating material from one or more gear pumps to the extrusion head.
9. The method of claim 8 , wherein the one or more gear pumps includes a planetary gear pump.
10. The method of claim 8 , wherein the one or more gear pumps include a plurality of non-planetary gear pumps.
11. The method of claim 8 , wherein the one or more gear pumps include at least one planetary gear pump and at least one non-planetary gear pump.
12. A method for extrusion comprising:
providing a plurality of metered, separate individual streams of extrusion material from one or more gear pumps to an extrusion head;
expanding each of the plurality of metered, separate individual streams of extrusion material in a plurality of corresponding respective expansion regions of a flow joiner;
joining, at an annular space of the flow joiner, the individual streams into an annular flow, each of the plurality of corresponding respective expansion regions having a first end adjacent each of a plurality of corresponding respective receiving regions, each of the plurality of corresponding respective expansion regions having a second end adjacent the annular space, the second end being wider than the first end, the plurality of corresponding respective expansion regions each having a substantially triangular shape;
tapering the annular flow to a tip and die; and
extruding the annular flow.
13. The method of claim 12 further comprising extruding the flow as a coating material on a substrate.
14. The method of claim 13 , wherein the substrate is metal conductor core and the coating material is an insulation layer.
15. The method of claim 12 , wherein one or more individual streams include a color different from one or more other individual streams.
16. The method of claim 12 , wherein at least two individual streams each include a different extrusion material.
17. The method of claim 12 , further comprising joining a second annular flow on a second tapered surface of the extrusion head, extruding the second annular flow on to an underlying annular flow and extruding multiple layers of extrusion material.
18. The method of claim 12 , further comprising extruding the flow as an annular end-product selected from the group consisting of a hose, tube, conduit, pole and pipe.
19. The method of claim 12 , further comprising metering the flow of individual streams with one or more gear pumps selected from the group consisting of a non-planetary and planetary gear pump.
20. The method of claim 1 , wherein joining the expanded plurality of metered, separate individual streams from the plurality of corresponding respective expansion regions of the flow joiner into the coating flow at the annular space comprises joining the expanded plurality of metered, separate individual streams from the plurality of corresponding respective expansion regions each having a respective arcuately shaped bottom congruent with the annular space.
21. The method of claim 1 , wherein providing the plurality of metered, separate individual streams of coating material to the extrusion head comprises providing the plurality of metered, separate individual streams of coating material to the extrusion head through a plurality of respective hoses.
22. The method of claim 1 , wherein expanding each of the plurality of metered, separate individual streams of coating material in the plurality of corresponding respective expansion regions comprises expanding each of the plurality of metered, separate individual streams of coating material wherein each of the plurality of corresponding respective expansion regions is approximately 1 ¾ in. long between each of the plurality of corresponding respective receiving regions and the annular space.
23. A method for coating a substrate comprising:
receiving a plurality of metered, separate individual streams of coating material at a plurality of corresponding respective receiving regions of a flow joiner within an extrusion head;
expanding each of the plurality of metered, separate individual streams of coating material in a plurality of corresponding respective expansion regions of the flow joiner;
joining the expanded plurality of metered, separate individual streams from the plurality of corresponding respective expansion regions of the flow joiner into a coating flow at an annular space of the flow joiner, each of the plurality of corresponding respective expansion regions having a first end adjacent each of the plurality of corresponding respective receiving regions, each of the plurality of corresponding respective expansion regions having a second end adjacent the annular space, the second end being wider than the first end, each of the plurality of corresponding respective expansion regions having a respective arcuately shaped bottom congruent with the annular space, the plurality of corresponding respective expansion regions each having a substantially triangular shape; and
extruding the coating flow on to a substrate comprising an electrical cable assembly.