An apparatus for manufacturing a multi-layer pipe is provided. The apparatus includes a ram extruding a matrix pipe, which is formed by inserting one or more insert pipes having different diameters into a receiving pipe, with a constant compression force, a heat-treatment unit heat-treating the matrix pipe extruded from the ram, and a drawing unit drawing, with a constant drawing force, the matrix pipe passing through the heat-treatment unit into a multi-layer pipe having a predefined diameter.

The production method for producing a rifled tube, which includes a plurality of first helical ribs on its inner surface, includes: a steps of: preparing a steel tube; and producing a rifled tube by performing cold drawing on a steel tube by using a plug which includes a plurality of second helical ribs, the plug satisfying Formulae and:

0.08 <W×(A−B)×N/(2π×A)<0.26  (1)

0.83<S×(A−B)×N/(2×M)<2.0  (2) where, W is a width of a groove bottom surface of the helical groove; A is a maximum diameter of the plug; B is a minimum diameter of the plug; N is a number of the second helical ribs; S is the width of the groove bottom surface; and M is a pitch of adjacent second helical ribs.

A method of manufacturing an aerosol generation system heater element is described. The aerosol generation system heater element comprising a seamless hollow tube, and the method comprises deforming a wall of a hollow tube to form the seamless hollow tube, the seamless hollow tube having a deformed wall, wherein the deformed wall of the seamless hollow tube is thinner than the wall of the hollow tube.

A method and an apparatus for axially shaping a tube use a mandrel guided in the tube and an annular die guided on the outside of the tube. The tube is clamped in a clamping device. The outer diameter of the tube is reduced by moving the annular die in a pushing direction. In order to form undercuts on the outside and inside of the tube the method uses the following steps: Reversing the direction of movement of the die and the mandrel upon reaching an end position from the pushing direction to an opposite pulling direction. In a first setting step, the die and the mandrel are then moved in relation to one another to a first preset annular-gap setting, and in a subsequent first shaping step, the die and the mandrel are moved in the pulling direction, while maintaining the preset annular gap.

A method for producing seamless pipes and an extruder are provided, including: S1, sleeving an ingot holding cylinder on an upsetting shaft and feeding an aluminum bar; S2, moving the ingot holding cylinder backwards; S3, squeezing the aluminum bar by an extrusion plug; S4, after upsetting, moving the ingot holding cylinder and the extrusion plug back to one side away from the upsetting shaft; S5, removing the upsetting shaft and installing a mold on the mold shaft; S6, perforating the aluminum bar after upsetting by a perforating needle; S7, extruding the perforated aluminum bar by the extrusion plug. The aluminum bar after upsetting keeps the same central axis as the extruder centerline and the ingot holding cylinder. The seamless pipes extruded from the mold are uniform, thereby improving their concentricity and finished product rate.

A lumen stent preform is provided using a plasma nitriding technology, a preparation method thereof, a method for preparing a lumen stent by using the preform, and a lumen stent obtained according to the method. The preform is manufactured by using pure iron or an iron alloy containing no strong nitrogen compound, has a hardness of 160-250HV0.05/10, and has a microstructure that is a deformed structure having a grain size number greater than or equal to 9 or a deformed structure after cold machining. Alternatively, the preform is an iron alloy containing a strong nitrogen compound, and has a microstructure that is a deformed structure having a grain size number greater than or equal to 9 or a deformed structure after cold machining. The lumen stent preform meets the requirements of a conventional stent for radial strength and plasticity, so that plasma nitriding is applicable to commercial preparation of a lumen stent.

A drawing machine (1) for drawing a tube (2), defining a longitudinal axis (Y), comprising a first die (3) for carrying out the drawing of the tube by means of the use of a mandrel (4); a device for varying the inclination (5) of the tube inlet into said first die (3); a second die (6) for carrying out a skin pass operation on the tube, arranged downstream of said first die (3); an in-line system for detecting the eccentricity of the tube; a data processing system (7) for processing signals originating from said detection system and sending input data to said device for varying the inclination (5) of the tube to vary the inclination of the tube so as to correct the eccentricity of the tube in-line; wherein said in-line system for detecting the eccentricity of the tube comprises a first detection head comprising at least three first transducers (8) arranged downstream of said first die (3).

A drawing machine (1) for drawing a tube (2), defining a longitudinal axis (Y), comprising a first die (3) for carrying out the drawing of the tube by means of the use of a mandrel (4); a device for varying the inclination (5) of the tube inlet into said first die (3); a second die (6) for carrying out a skin pass operation on the tube, arranged downstream of said first die (3); an in-line system for detecting the eccentricity of the tube; a data processing system (7) for processing signals originating from said detection system and sending input data to said device for varying the inclination (5) of the tube to vary the inclination of the tube so as to correct the eccentricity of the tube in-line; wherein said in-line system for detecting the eccentricity of the tube comprises a first detection head comprising at least three first transducers (8) arranged downstream of said first die (3).

Provided is a thin, narrow tube for use in a biodegradable medical device formed from a round tube made of a magnesium material as the base material, in which a desired outer diameter and an inner diameter are provided with good precision over the entire region in a longitudinal direction and a circumferential direction, and the length of biodegradation time can be controlled without changing a material composition. The thin, narrow tube is a thin, narrow tube of a biodegradable medical device, in which the thin, narrow tube is a round tube made of crystals containing magnesium (Mg) having a hexagonal crystal structure, and when the crystals forming the round tube are viewed in a round tube axis direction of the round tube, a hexagonal basal plane (0001) is oriented at a predetermined inclination angle with respect to a circumferential direction perpendicular to a radial direction (a direction from an inner surface to an outer surface) of the round tube.

Provided is a thin, narrow tube for use in a biodegradable medical device formed from a round tube made of a magnesium material as the base material, in which a desired outer diameter and an inner diameter are provided with good precision over the entire region in a longitudinal direction and a circumferential direction, and the length of biodegradation time can be controlled without changing a material composition. The thin, narrow tube is a thin, narrow tube of a biodegradable medical device, in which the thin, narrow tube is a round tube made of crystals containing magnesium (Mg) having a hexagonal crystal structure, and when the crystals forming the round tube are viewed in a round tube axis direction of the round tube, a hexagonal basal plane (0001) is oriented at a predetermined inclination angle with respect to a circumferential direction perpendicular to a radial direction (a direction from an inner surface to an outer surface) of the round tube.