An apparatus for preparing a tube end for rod drawing with a floating mandrel has a releasable holder for the tube end centered on an axis, a frustoconical and spreadable floating mandrel, and a device for inserting the mandrel into the tube end and spreading the mandrel to flare the tube end. The apparatus further has a feed mechanism for inserting the floating mandrel into the tube end and/or a deforming device for making at least one indentation in the tube for holding the floating mandrel.

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(AB)N/(2A)<0.26(1)
0.83<S(AB)N/(2M)<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.

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(AB)N/(2A)<0.26(1)
0.83<S(AB)N/(2M)<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.

This invention concerns a tubular element for a gas pressure vessel of an airbag module, in particular of a vehicle, wherein the tubular element (1) consists of high-strength steel, has a first and a second end (17, 18) and from the first end (17) to the second end (18) the tubular element (1) has an undeformed section (11), a transition section (12) and a tapering section (13) and on the tapering section (13) at least one radially outwardly extending collar (14) is formed, characterized in that the collar (14) is separated from the transition section (12) by a first length section (130) having an outer diameter (A1) smaller than the outer diameter (A2) of the collar (14) and the wall thickness of the collar (14) is greater than the wall thickness of the first length section (130). Furthermore, the invention concerns a gas pressure vessel and a process for manufacturing a tubular element according to the invention (1).

This invention concerns a tubular element for a gas pressure vessel of an airbag module, in particular of a vehicle, wherein the tubular element (1) consists of high-strength steel, has a first and a second end (17, 18) and from the first end (17) to the second end (18) the tubular element (1) has an undeformed section (11), a transition section (12) and a tapering section (13) and on the tapering section (13) at least one radially outwardly extending collar (14) is formed, characterized in that the collar (14) is separated from the transition section (12) by a first length section (130) having an outer diameter (A1) smaller than the outer diameter (A2) of the collar (14) and the wall thickness of the collar (14) is greater than the wall thickness of the first length section (130). Furthermore, the invention concerns a gas pressure vessel and a process for manufacturing a tubular element according to the invention (1).

The invention relates to a twist-axle that includes a cross-beam member and two trailing arms, each trailing arm rigidly secured to the cross-beam member in one of two connection regions of the cross-beam member or formed integrally with and extending from one of the two connection regions. The cross-beam member is formed from a tubular blank and has a torsionally elastic central portion and two torsionally stiff connection regions. The cross-beam member has a wall thickness that varies longitudinally along the length of the cross-beam member from the torsionally elastic central portion to each of the torsionally stiff connection regions.

The invention relates to a twist-axle that includes a cross-beam member and two trailing arms, each trailing arm rigidly secured to the cross-beam member in one of two connection regions of the cross-beam member or formed integrally with and extending from one of the two connection regions. The cross-beam member is formed from a tubular blank and has a torsionally elastic central portion and two torsionally stiff connection regions. The cross-beam member has a wall thickness that varies longitudinally along the length of the cross-beam member from the torsionally elastic central portion to each of the torsionally stiff connection regions.

Invention relates to is a mandrel adjustment assembly for multi-wall pipe made of a coated metal sheet comprising; a bearing positioning an elongated mandrel over a tray by holding; a distance adjustment unit having an adjustment member adjusting a stroke distance of mandrel by changing axial location of bearing; a first support and a second support holding mandrel over a tray such that the mandrel is freely movable between a distal end and an opposite proximal end. A distance adjustment unit is equipped with a display enabling visual access to a stroke distance set by an adjustment arm and the distance adjustment unit move the mandrel over the tray providing a displacement equal to stroke distance.

Invention relates to is a mandrel adjustment assembly for multi-wall pipe made of a coated metal sheet comprising; a bearing positioning an elongated mandrel over a tray by holding; a distance adjustment unit having an adjustment member adjusting a stroke distance of mandrel by changing axial location of bearing; a first support and a second support holding mandrel over a tray such that the mandrel is freely movable between a distal end and an opposite proximal end. A distance adjustment unit is equipped with a display enabling visual access to a stroke distance set by an adjustment arm and the distance adjustment unit move the mandrel over the tray providing a displacement equal to stroke distance.

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.