Method and device for molding small-angle bent pipe fitting by taking different curved surfaces as extrusion surfaces

The invention discloses a method and a device for molding a small-angle bent pipe fitting by taking different curved surfaces as extrusion surfaces, and relates to a preparation technology for medium and thin-wall bent pipe fittings. A metal blank is subjected to extrusion molding through the molding device taking different curved surfaces as the extrusion surfaces; and the device comprises a mould molding part, a mould fixing part and a guide part. The invention has the advantages that: a female die and a male die of the mould molding part and a central line of a spindle are in the same straight line in the extrusion molding device of the bent pipe fitting; and the mould is convenient to assemble and easy to adjust. The bent pipe fitting is prepared by changing the shape and the concave-convex degree of a curved surface at the discharge end of the female die; the device has a rational structure and a simple process; and the bent pipe fitting has uniform wall thickness, does not crinkle, and has a cross section free from distortion, reliable quality and a broad application prospect.