A method for producing a metal cylinder includes preparing a metal slug having a surface adjusted so that the crystal grain diameter at a depth of 10 m from the surface is smaller than that at a depth of 100 m from the surface, and the crystal grain diameter at a depth of 10 m from the surface is 30 m or more and 120 m or less; and forming a cylinder by impact pressing of the metal slug having the surface as a bottom.

A method for producing a metal cylinder includes preparing a metal slug having a surface adjusted so that the crystal grain diameter at a depth of 10 m from the surface is smaller than that at a depth of 100 m from the surface, and the crystal grain diameter at a depth of 10 m from the surface is 30 m or more and 120 m or less; and forming a cylinder by impact pressing of the metal slug having the surface as a bottom.

A method and a former for necking and thickening a tube end. The former includes a hydraulic cylinder, a pusher, a concave die, a filler block, a plurality of heating rods and a heating device. The hydraulic cylinder is connected to a disc provided with a guide sleeve. The pusher is provided on the hydraulic cylinder and passes through the guide sleeve. The concave die is provided at a side of the pusher and includes a mold cavity and a plurality of heating holes. The filler block is provided in the mold cavity. The heating rods are provided in the heating holes connected to the heating device. The filler block includes a tapered portion provided at one end of the filler block and a diameter-reduced portion. The tapered portion is threadedly connected to the diameter-reduced portion. An ejector pin is provided at one end of the diameter-reduced portion.

A method and a former for necking and thickening a tube end. The former includes a hydraulic cylinder, a pusher, a concave die, a filler block, a plurality of heating rods and a heating device. The hydraulic cylinder is connected to a disc provided with a guide sleeve. The pusher is provided on the hydraulic cylinder and passes through the guide sleeve. The concave die is provided at a side of the pusher and includes a mold cavity and a plurality of heating holes. The filler block is provided in the mold cavity. The heating rods are provided in the heating holes connected to the heating device. The filler block includes a tapered portion provided at one end of the filler block and a diameter-reduced portion. The tapered portion is threadedly connected to the diameter-reduced portion. An ejector pin is provided at one end of the diameter-reduced portion.

A friction assisted tube fabrication method is disclosed. The friction assisted tube fabrication includes a set of methods such as a friction assisted tube forming, a friction assisted tube extrusion, and a friction assisted tube straining method. A metal object, for example, a deformable tube is simply deformed into the tube using a mandrel. The metal object with an initial diameter is forced across the slope of the mandrel with an angle. The mandrel is configured to rotate while forcing the metal object to deform into the tube with the desired radius. While rotating the mandrel, a friction is generated due to contact between the tube and the mandrel, thereby generating thermal energy to heat a deformation area of the tube for simply and easily softening and forming into the desired shape with accuracy diameter, and dimensions using a nominal pressing force without additional equipment and power.

A method is used to manufacture an article using a machine having a fixed base and a press structure movable toward the fixed base. The machine also includes a die assembly and a container both coupled to the fixed base. The machine further includes a mandrel assembly comprising a rotatable platform coupled to the press structure and having a first platform mandrel aligned with the die assembly and a second platform mandrel aligned with the container. The method includes the steps of placing a first starting component into the die assembly, pressing the first starting component to form the article, moving the second platform mandrel into the container simultaneously with the step of pressing the first starting component, and rotating the rotatable platform to align the second platform mandrel with the die assembly and to align the first platform mandrel with the container.

A method is used to manufacture an article using a machine having a fixed base and a press structure movable toward the fixed base. The machine also includes a die assembly and a container both coupled to the fixed base. The machine further includes a mandrel assembly comprising a rotatable platform coupled to the press structure and having a first platform mandrel aligned with the die assembly and a second platform mandrel aligned with the container. The method includes the steps of placing a first starting component into the die assembly, pressing the first starting component to form the article, moving the second platform mandrel into the container simultaneously with the step of pressing the first starting component, and rotating the rotatable platform to align the second platform mandrel with the die assembly and to align the first platform mandrel with the container.

A method is used to manufacture a tube having a hollow interior for housing an axle shaft. The tube is formed in a single machine having a fixed base and a single press structure movable toward the fixed base. The single machine includes first and second die assemblies coupled to the fixed base and first and second mandrels coupled to the single press structure. The method includes the steps of placing a billet into the first die assembly, pressing the billet into the first die assembly with the first mandrel to producing a pre-formed billet, and moving the pre-formed billet from the first die assembly to the second die assembly. THE method further includes the steps of pressing the pre-formed billet into the second die assembly with the second mandrel to elongate the pre-formed billet and form a hollow interior therein to produce an extruded tube.

A method is used to manufacture a tube having a hollow interior for housing an axle shaft. The tube is formed in a single machine having a fixed base and a single press structure movable toward the fixed base. The single machine includes first and second die assemblies coupled to the fixed base and first and second mandrels coupled to the single press structure. The method includes the steps of placing a billet into the first die assembly, pressing the billet into the first die assembly with the first mandrel to producing a pre-formed billet, and moving the pre-formed billet from the first die assembly to the second die assembly. THE method further includes the steps of pressing the pre-formed billet into the second die assembly with the second mandrel to elongate the pre-formed billet and form a hollow interior therein to produce an extruded tube.

A damper housing disposed on a center axis includes an extended mains section and a narrowed end section. The narrowed end section has a second predetermined wall thickness less than the first predetermined wall thickness of the extended main section. An intermediate conical section, connecting the narrowed end section and the extended main section, has an intermediate conical section wall thickness equal to the second predetermined wall thickness at an internal inclination angle relative to the center axis. A method for manufacturing the damper housing using a preformed tube, a first broaching die, a calibrating mandrel, and a swaging die is performed by compressing the preformed tube between the first broaching die and the narrowed head of the calibrating mandrel and compressing the preformed tube between the swaging die and the intermediary section of the calibrating mandrel to form the narrowed end section and the intermediate conical section, respectively.