Direct or indirect metal pipe extrusion process, mandrel for extruding metal pipes, metal pipe extruder and extruded metal pipe
AssigneeSMS Meer GmbH
InventorsUwe Muschalik, Jens Magenheimer, Anna Rott, Koos van Putten
Life of this patent
Estimating the term…
Abstract
If a mandrel for extruding metal pipes, having two axially offset pressing surfaces with different radial embossing and having a transition region between these two pressing surfaces has a support surface in the transition region then the negative effect of narrowing, which arises owing to the mandrel shifting from a first pressing position, in which the first of the two pressing surfaces interacts with a die, to a second pressing position, in which the second pressing surface interacts with the die, can be minimized.
Claims16
Direct or indirect metal pipe extrusion method, in which a metal block (5) is pressed to form a metal pipe (9), through a die (2) and by way of a mandrel (6), wherein the mandrel (6) has two pressing surfaces (63, 64) disposed to be axially offset and having different radial characteristics, and is optionally positioned in two pressing positions, axially with reference to the die, in such a manner that in a first one of the two pressing positions, a first one of the two pressing surfaces (63, 64) acts on the work piece pressed from a metal block (5) into a metal pipe (9), forming it, and in a second of the two pressing positions, a second of the two pressing surfaces (63, 64) acts on it, wherein the work piece is supported, on the mandrel side, at the axial height of the die (2), while the mandrel (6) is positioned, with regard to the die (2), from the first pressing position to the second position.
Mandrel (6) for pressing metal pipes (9), having two pressing surfaces (63, 64) disposed to be axially offset and having different radial characteristics, and having a transition region (66) between the two pressing surfaces (63, 64), wherein the mandrel (6) has a supporting surface (62) in the transition region (66).
Extruded metal pipe (9) having two different wall thicknesses and a transition region situated between the wall thicknesses, wherein a constriction (E) is present in the transition region, comprising at least two constrictions (E).
Extruded metal pipe (9) having two different wall thicknesses and a transition region situated between the wall thicknesses, wherein a constriction (E) is present in the transition region, wherein in the region of the constriction (E), the wall thickness is greater than the smaller of the two wall thicknesses.
Extruded metal pipe (9) having two different wall thicknesses and a transition region situated between the wall thicknesses, wherein a constriction (E) is present in the transition region, wherein the constriction (E) has a depth that is less than the difference of the two wall thicknesses.
Extruded metal pipe (9) having two different wall thicknesses and a transition region situated between the wall thicknesses, wherein a constriction (E) is present in the transition region, wherein the constriction (E) has a length that is greater than the difference of the two wall thicknesses.
Dependencies are inferred from the claim text.