A method for producing a seamless metal pipe includes the steps of: preparing a billet having a diameter (B); heating the billet; forming, in a center part of a rear end of the heated billet, a hole including four grooves extending in an axial direction of the billet, the grooves each having a groove width (D) satisfying Formula (1), a groove height (H) satisfying Formula (2), and a groove depth (L1) satisfying Formula (3); and subjecting the billet provided with the hole to piercing-rolling from a front end thereof by means of a piercing machine. By this means, the generation of burrs and internal defects at the rear end of a hollow shell after piercing-rolling can be suppressed.

0.12D/B0.25 (1)

0.10H/B0.20 (2)

0.05L1/B0.10 (3)

A method for manufacturing a cold-forged, extruded aluminum alloy tube includes the steps of: providing a primary material having a hollow columnar shape and made of an aluminum alloy material, and a first cold extrusion apparatus; processing the primary material to form a preform; subjecting the preform to a homogeneous annealing by heating to a temperature of about 410 C. to 510 C. and then cooling to a temperature of about 160 C. to 200 C.; testing the hardness of the preform; immersing the preform in a tank containing lubricant having a total acidity concentration of 40 to 50 mg/L at a working temperature of 80 C. to 100 C.; and subjecting the preform to cold extrusion.

The invention relates to a bridge tool for a device for directly extruding hollow profiled elements of variable wall thickness, comprising a die (6) and at least one mandrel element (5) having a first end facing the die opening and an opposite second end, the outer profile contour of a hollow profiled element being defined by the geometry of the die opening and the inner cross-section of a hollow profiled element being defined by the at least one mandrel element (5), characterized in that the at least one mandrel element (5) has at least one cut-out, in which an inner sliding mandrel is arranged, said inner sliding mandrel being mounted for movement in the axial direction, the inner sliding mandrel having different cross-sections in the first end region of the inner sliding mandrel facing the first end of the mandrel element.

In this flat extruded aluminum multi-port tube, the corrosion-resistance, at inner surfaces of a plurality of flow passages independently and parallelly extending in the tube axial direction, is effectively enhanced. In a flat extruded aluminum multi-port tube 10 formed by an extrusion by employing an aluminum tube material and an aluminum sacrificial anode material having an electrochemically lower potential than the aluminum tube material, the aluminum sacrificial anode material is exposed to form a sacrificial anode portion 18 at least in a part of an inner circumferential portion in each of the plurality of flow passages 12.

Method of producing a tube of duplex stainless steel is disclosed. The steel comprises the following composition, in weight %: C max 0.03, Si max 1.0, Mn max 1.5, P max 0.05, S max 0.03, Cr 24-26, Ni 6-8, Mo 3.0-4.0, N 0.24-0.32. The method comprises steps of: forming a tube of the duplex stainless steel, cold working the tube obtained from the step of forming a tube, and soft annealing the tube after the step of cold working by subjecting the tube to a temperature, T, within a range of 500-750 C. for a time period, t, of 0.5-5 minutes.

Systems, devices, and methods are described for extruding materials. In certain embodiments, one or more hollow billets are loaded onto an elongate mandrel bar and transported along the mandrel bar to a rotating die. The billets are transported through fluid clamps, which engage the mandrel bar and provide cooling fluid to the mandrel bar tip, and through mandrel grips, which engage the mandrel bar and prevent the mandrel bar from rotating. One or more press-rams advance the billets through a centering insert and into the rotating die. A quench assembly is provided at an extrusion end of the extrusion press to quench the extruded material. A programmable logic controller may be provided to control, at least in part, operations of the extrusion press system.

Systems, devices, and methods are described for extruding materials. In certain embodiments, one or more hollow billets are loaded onto an elongate mandrel bar and transported along the mandrel bar to a rotating die. The billets are transported through fluid clamps, which engage the mandrel bar and provide cooling fluid to the mandrel bar tip, and through mandrel grips, which engage the mandrel bar and prevent the mandrel bar from rotating. One or more press-rams advance the billets through a centering insert and into the rotating die. A quench assembly is provided at an extrusion end of the extrusion press to quench the extruded material. A programmable logic controller may be provided to control, at least in part, operations of the extrusion press system.

A drive axle shaft and method for making the same are provided. The drive axle shaft includes an elongate tubular body and a wheel flange. The elongate tubular body has a longitudinal axis and comprises a first end portion and a second end. The second end is configured to be coupled to a side gear in a differential. The wheel flange is disposed at the first end portion and is configured to support a vehicle wheel. The elongate tubular body and the wheel flange are formed as a unitary body without any weld therebetween.

An oil mist filter includes: a filter body having a tubular shape, the filter body causing processing-target gas supplied to a hollow in the filter body pass through an outer peripheral surface to capture oil mist contained in the processing-target gas; and an end plate disposed at one end surface of the filter body the end plate projecting outward beyond an outer peripheral edge of the one end surface of the filter body. A plurality of ventholes are formed at a portion of the end plate projecting beyond the outer peripheral edge of the one end surface of the filter body. The processing-target gas blown out from the outer peripheral surface of the filter body passes through the ventholes.

A hot extrusion die for a special-shaped square pipe includes a die cavity sleeve with a special-shaped cavity. A hot extrusion mandrel is arranged in the die cavity sleeve. An area between the die cavity sleeve and the hot extrusion mandrel forms a die cavity hole. A first extrusion diversion hole and a second extrusion diversion hole are arranged below the die cavity hole. An integral centroid of the die cavity hole is located at a circle center of a radial cross section of the die cavity sleeve. Further disclosed is a hot extrusion integral forming method for a special-shaped square pipe, including: heating and expanding a blank material; heating the blank material again after expanding; performing hot extrusion on the blank material; and cooling the formed special-shaped square pipe in air to a room temperature, and inspecting surface quality and mechanical properties of the special-shaped square pipe.