A stretch-reducing mill (1) for producing seamless pipes (R), which comprises a plurality of roll stands (10), which are arranged one after the other in a conveying direction (F) of the pipes (R) and each have three rolls (11) arranged at an angular distance of 120, wherein the roll stands (10) are divided into at least two groups (A, B) each having at least two roll stands (10); the rolls (11) of adjacent roll stands (10) within a group (A, B) are inclined relative to each other by an intra-group angle I; and the rolls (11) of the roll stands (10) of adjacent groups (A, B) are inclined relative to each other by a group angle G that is less than the intra-group angle I.

A method for producing hot-rolled, seamless pipes having at least one wall thickening which can be arranged at any positions over the length of the pipe, wherein by means of a multiple-stand mandrel bar rolling mill, the rolls roll a hollow shell on a mandrel bar as an inner tool to a required nominal wall thickness and produce at specified positions over the length of the pipe a required wall thickening on the outer side of the pipe by opening the rolls in the rolling stands. The thickened wall is produced and finish-rolled by two rolling stands that are consecutive as seen in the rolling direction, in which the deviations of the finished contour of the thickening from an ideal circular cross-section are minimised, wherein the rolling stands located upstream are likewise opened as to avoid any contact of the rolls of these rolling stands with the previously produced thickening.

The invention relates to an apparatus (1) for producing a peripheral groove (101) in an end portion (103) of a metal tube (100), in particular a metal tube (100) which is to be coated on the inside, the groove (101) being set up for receiving tube connectors, having a first, rotationally driven roller (3), a second, freely rotating roller (5), the first roller (3) having a roughened or structured surface (6) relative to the second roller (5), a pressing device (15) for producing a relative movement between the first and second roller (3, 5), between a first and a second position, the rollers (3, 5) assuming a first spacing from one another in the first position, which first spacing permits an introduction of a wall of the tube between the rollers (3, 5), and assuming a smaller, second spacing from one another in the second position, which second spacing is smaller than a material thickness (M) of the wall of the tube.

It is proposed according to the invention that the first, driven roller (3) is set up to grip the tube from the outside in the second position and to rotate it, with the result that a peripheral groove (101) is pressed into the tube in the second position when the first roller (3) is driven.

Provided is a method for performing an external pipe thread process on a hollow blank by at least twice rolling: firstly, the first rolling wheel group rolls the outer surface of the hollow blank into a threaded cylindrical surface or a threaded conical surface or a threaded cylindrical conical mixing surface, and secondly, the second rolling wheel group rolls again for the outer surface of the hollow blank which has processed in step 1, and rolling to form an external pipe thread; wherein the number of rolling wheels in a rolling wheel group, used in any two back-to-back rolling processes in a processing sequence, are different in parity. Further provided are various rolling head, module, apparatuses and production line for pipe thread, achieving the above processing method and having a simple structure, portability and practicality. When preforming an external pipe thread rolling process of the hollow blank, thereby improving a processing yield; in addition, the invention also provides a threaded cylindrical surface or a threaded conical surface or threaded cylindrical conical mixing surface products by the first rolling wheel group.

The present invention relates to a forge rolling device (1) for the bending forge rolling of a component (2), in particular of a component blank, having a first forging roll (10) with a first axis of rotation (R), and a second forging roll with a second axis of rotation, wherein each of the forging rolls (10) has, on its surface (11), a forge rolling contour (12) that runs at least partially around its axis of rotation (R), said forge rolling contours (12) corresponding to one another, in order to form a component (2) passed between the forging rolls (10) in a passage direction (D). This forming can be bending with or without cross-sectional change. In this case, the forge rolling contours (12) are configured so as to bend the component (2), passed between the forging rolls (10), in at least one direction transversely to the passage direction (D) of the component (2), at least by means of one subregion (13) of the forge rolling contours (12). The present invention also relates to a method for the bending forge rolling of a component (2) and to a component (2) produced with the method according to the invention.

A calcium-bearing magnesium and rare earth element alloy consists essentially of, in mass percent, zinc (Zn): 1-3%; aluminum (Al): 1-3%; calcium (Ca): 0.1-0.4%; gadolinium (Gd): 0.1-0.4%; yttrium (Y): 0-0.4%; manganese (Mn): 0-0.2%; and balance magnesium (Mg).

The invention relates to an apparatus (1) for producing a peripheral groove (101) in an end portion (103) of a metal tube (100), in particular a metal tube (100) which is to be coated on the inside, the groove (101) being set up for receiving tube connectors, having a first, rotationally driven roller (3), a second, freely rotating roller (5), the first roller (3) having a roughened or structured surface (6) relative to the second roller (5), a pressing device (15) for producing a relative movement between the first and second roller (3, 5), between a first and a second position, the rollers (3, 5) assuming a first spacing from one another in the first position, which first spacing permits an introduction of a wall of the tube between the rollers (3, 5), and assuming a smaller, second spacing from one another in the second position, which second spacing is smaller than a material thickness (M) of the wall of the tube. It is proposed according to the invention that the first, driven roller (3) is set up to grip the tube from the outside in the second position and to rotate it, with the result that a peripheral groove (101) is pressed into the tube in the second position when the first roller (3) is driven.

A rolling mill roll according to the present invention includes: a shaft member which rotates around an axial line; a rolling ring which is fitted to an outer circumferential surface of the shaft member; a support portion which is provided on the outer circumferential surface of the shaft member; an interposed ring which is fitted to the outer circumferential surface of the shaft member and is provided on the other side of the rolling ring in the axial line direction; a pressing nut which is screwed onto the outer circumferential surface of the shaft member and is disposed to be adjacent to the other side of the interposed ring; a screw hole which is formed to penetrate the pressing nut in the axial line direction; and a screw shaft which is screwed into the screw hole and which is capable of pressing the interposed ring toward the one side in the axial line direction.

Disclosed within is a slit section pass formation unit having a pair of rolls and a de-ribbing means, where the pair of rolls has a roll profile configured to produce a pair of slit rods with symmetrical dimensions, the pair of slit rods connected via a rib, and the de-ribbing means to remove the rib in its entirety forming a first slit rod and a second slit rod.

A method disclosed herewith is a method for producing a first seamless metal tube with a first wall thickness and a second seamless metal tube with a second wall thickness by using a three-roll-type inclined rolling mill, and the method includes a first inclination rolling step (#5), a setting changing step (#10), and a second inclination rolling step (#15). At the first inclination rolling step, a first workpiece is rolled by the inclined rolling mill. At the setting changing step, a setup condition of the inclined rolling mill is changed in a manner (a) or (b) as described below. At the second inclined rolling step, a second workpiece is rolled by the inclined rolling mill under the changed condition. (a) When the second wall thickness is smaller than the first wall thickness, the cross angle of each of the inclined rolls is made greater than the cross angle set for the first inclination rolling step. (b) When the second wall thickness is larger than the first wall thickness, the cross angle of each of the inclined rolls is made smaller than the cross angle set for the first inclination rolling step.