An apparatus for backward flow forming a material may comprise a mandrel having a headstock at a proximate end of the mandrel, the mandrel configured to rotate about an axis, a plurality of rollers disposed radially outward of the mandrel configured to exert force on the material to form a work piece at a plastic deformation zone, wherein the work piece flows from the plastic deformation zone between the plurality of rollers and the mandrel toward a distal end of the mandrel, and a catcher, coaxial to the mandrel, and removably coupled to the work piece at a traveling end of the work piece.

A press device includes: a first die having a shape of an elliptical cylinder; a second die having a first recess that forms a part of an elliptical-cylindrical space configured to arrange the first die therein; a third die having a second recess to be combined with the first recess to form the elliptical-cylindrical space; a first press mechanism that inserts the first die along a radial direction of the first die to the first recess of the second die over which the flat metal stock is placed so as to press the metal stock; and a second press mechanism that moves the third die relative to the first die inserted to the first recess so as to confine the first die and the metal stock in the elliptical-cylindrical space formed by the first recess and the second recess.

A forming apparatus that forms a metal pipe material includes an electrode that holds the metal pipe material and supplies electric power to the metal pipe material to heat the metal pipe material, a forming die that quenches and forms the expanded metal pipe, and a member that suppresses quenching, in which a region where quenching is not performed in the metal pipe is adjusted by adjusting a length of the member.

A hot-spinning formation method for large-diameter titanium alloy cylindrical parts. A workblank is placed in a resistance furnace to heated to 600-650° C., is maintained at this temperature for 0.5-1 h and is then taken out of the resistance furnace; after the workblank is heated, the inner diameter of the workblank becomes larger; the heated workblank is installed on a mandrel, and spinning is started when a maximum clearance between the workblank and the mandrel is less than 0.5 mm; the mandrel and the spinning rollers do not need to be preheated, and a multi-pass spinning process is adopted, such that the workblank can deform more uniformly. A vertical spinning lathe is used for spinning, the mandrel is easy to change, and the workblank is easy to assemble and disassemble.

A hot-spinning formation method for large-diameter titanium alloy cylindrical parts. A workblank is placed in a resistance furnace to heated to 600-650° C., is maintained at this temperature for 0.5-1 h and is then taken out of the resistance furnace; after the workblank is heated, the inner diameter of the workblank becomes larger; the heated workblank is installed on a mandrel, and spinning is started when a maximum clearance between the workblank and the mandrel is less than 0.5 mm; the mandrel and the spinning rollers do not need to be preheated, and a multi-pass spinning process is adopted, such that the workblank can deform more uniformly. A vertical spinning lathe is used for spinning, the mandrel is easy to change, and the workblank is easy to assemble and disassemble.

A press machine includes: a ram, a shaft, and three or more ram driving cams, for the one ram, configured to push down the ram toward a bottom dead center, the plurality of ram driving cams being integrally rotatable with the common shaft. Both end portions of the shaft are rotatably supported by a pair of rotation support portions fitted to the both end portions between which all of the plurality of ram driving cams are disposed, and an intermediate portion of the shaft disposed between the ram driving cams is rotatably supported by a support groove opened downward. The plurality of ram driving cams includes at least two lifting and lowering cams configured to apply both a pushing down force and a pushing up force to the ram, and at least one lowering cam configured to apply only the pushing down force to the ram.

A method for producing a valve body of a hollow valve includes providing a workpiece blank or semi-finished product, spin extruding the workpiece to produce a preform having a cup with a hollow shape formed by the cup wall. A hollow valve produced by this method is also provided.

A method for producing a valve body of a hollow valve includes providing a workpiece blank or semi-finished product, spin extruding the workpiece to produce a preform having a cup with a hollow shape formed by the cup wall. A hollow valve produced by this method is also provided.

A method for manufacturing a steel Yankee drier including a cylindrical steel mantle with two end heads on each of which a corresponding pin is arranged, the cylindrical mantle having an external surface and an internal surface, and the internal surface of the mantle in cooperation with the end heads delimiting an internal chamber of the Yankee drier in which steam can be introduced. The surface protective coating is at least partially formed on the internal surface of the mantle by introducing a predetermined amount of a nickel bath in a volume delimited in a radial direction by the internal surface of the mantle, followed by a permanence of the bath in said volume for a predetermined time. The surface protective coating protects the internal surface of the mantle from corrosive and/or abrasive agents contained in the steam introduced into said chamber.

A method for manufacturing a steel Yankee drier including a cylindrical steel mantle with two end heads on each of which a corresponding pin is arranged, the cylindrical mantle having an external surface and an internal surface, and the internal surface of the mantle in cooperation with the end heads delimiting an internal chamber of the Yankee drier in which steam can be introduced. The surface protective coating is at least partially formed on the internal surface of the mantle by introducing a predetermined amount of a nickel bath in a volume delimited in a radial direction by the internal surface of the mantle, followed by a permanence of the bath in said volume for a predetermined time. The surface protective coating protects the internal surface of the mantle from corrosive and/or abrasive agents contained in the steam introduced into said chamber.