To improve the precision by arranging a shape correcting jig for correcting the cross sectional shape of an extruding shape come out from a forming gap into the proper cross sectional shape.
The shape correcting jig is provided at the tip part of a male die 6. This shape correcting jig is brought into sliding contact with the inner diameter surface of the extruded shape material come out from the forming gap 15 to widen the inner diameter shape of the extruded shape material, and the inner diameter shape of the extruded shape material is corrected to the proper cross sectional shape. Further, the front part in the extruding direction of the outer diameter of the jig is brought into sliding contact with the inner diameter surface of the extruded shape material. This jig is formed in the cross section as a cylindrical parallel part 10a and an inclining part 10b having the shape, in which the outer diameter becomes large toward the extruding direction, so as to guide the extruded shape material to the parallel part, at the rear part in the extruding direction. In the extruding apparatus, an aluminum billet B is charged in a container and introduced into the forming gap 15 by advance-driving a stem to extrude the extruded shape material E.
ISOGAI MITSUYUKI
AZUMA NOBUYUKI
