| 摘要 |
Apparatus for the continuous extrusion of metals in which feed is in- troduced into two (or more) spaced mart circumferential grooves (4) in a ro- tating wheel (2) (or rotating wheels) to contact an arcuate shoe portion (8) and abutments extending into the grooves. The feed is constrained by the abutments to flow through frusto-conical exit apertures (10) in the shoe por - tion (8) to a chamber (6) and is extruded as relatively thin-walled, large cross-section, product. The exit apertures (10) have cone angles in the rang e 5.degree.-45.degree.. Mixer plates (14) are profiled to distribute flow even ly from the ap- ertures ( 10) to around the die opening (30). An extrusion die body (18) for cylindrical extrusions is located and axially centered by set screws (122). Where an even number of grooves (4) are utilised, an extrusion mandrel (1 2) may be secured to the shoe portion (8) by a bolt (22) positioned centrally o f the grooves. Lubricant or oxidation inhibiting fluids may be injected inter- nally of the extruded product through a passage (36, 38) extending through the shoe portion (8) and the bolt (22). In another embodiment, the chamber (6) is also of divergent frusto-conical form having a cone angle correspond- ing to that of the apertures (10), thereby enabling the extrusion of even la rg- er cross-section products. The frusto-conical form may be of elliptical cros s- section to achieve a requisite divergence or to accord with the configuratio n of the die orifice. By providing spaced apart grooves (4) and apertures (10) diverging frusto-comically it is possible to extrude products of relatively large cross-section since the volume feed rate is enhanced and the distance travelled by the material from the grooves (4) to the die orifice (30) is re - duced, thereby reducing friction losses and the likelihood of discontinuitie s in the extrudate arising.
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