E.i. Dupont De Nemours and Company

Fabrice Aubertin

Daniel N Levy

An extrusion head for use in the paste extrusion of lubricated PTFE fine powder, the extrusion head comprising an external die having an inlet, a chamber, and an outlet, a tip positioned in the chamber of the die, the tip having a circumferential ridge formed therein that extends into the chamber, the chamber having a shape complementary to the ridge so as to form a space between the external die and the tip to allow lubricated PTFE fine powder to pass therethrough, and a mandrel which extends through the external die and supports the tip in the chamber.

Paste extrusion apparatus

The present invention relates to a process of paste extruding lubricated PTFE fine powder in an extrusion device by forcing the lubricated PTFE fine powder through the extrusion device and out of an orifice as a lubricated green extrudate, wherein before exiting through the orifice, the direction of the flow of the lubricated PTFE fine powder in the extrusion device is reoriented in a direction at least 60 degrees different from the initial direction of the flow of the lubricated PTFE fine powder through the extrusion device.

Paste extrusion method

Paste extrusion of lubricated PTFE fine powder is carried out by using the extrusion head of the extruder as the ram for forcing the powder through the extrusion orifice in the extrusion head, i.e. the extrusion head is moved against the powder, whether in particle form or preform form, to cause the extrusion.

Growing community of inventors

Segny, France

Fabrice Aubertin