Abstract: Pilger rolling mill for working a hollow into a tube has a first roll stand mounted linearly moveable in a direction of motion. Translational motion of the roll stand causes rotational motion of the drive gear due to the cogging of the drive gear with the gear rack and, hence, also rotational motion of the roller arranged on the shaft of the drive gear and rotational motion of the other one of the two rollers in the opposite direction. Roll stand is connected with a crank drive and rotational motion of a motor drive is transformed into an oscillating translational motion of the roll stand by a connecting rod. Gear rack holder allows adjustment of the pilger rolling mill with respect to tube diameters of finished rolled tubes by arranging the first roll stand exchangeable by a second roll stand with a second dimension being different from the first dimension.

Abstract: A die roll 3 comprises a core part 3a which is formed of an elastic material and faces a punch part 2a of a punch roll 2. The core part 3a presses a bottom portion 4b of a drawn portion 4a of a metal material 4 and is separate from a surrounding die part 3b and is provided with a space 3c at the whole outer periphery of the core part 3a. In accordance with the above configuration, swelling is suppressed at the bottom portion 4b of the drawn portion 4a and production of large wrinkles, which is a reason for folds, can be prevented by increase of pressing areas for preventing wrinkles at both sides of the drawn portion.

Abstract: A method for smoothing and compacting a weld on a cylindrical support sleeve includes mounting the support sleeve on an abutment and moving a device across the support sleeve such that a roller on the support sleeve rolls on the weld under pressure so that it smooths and levels the weld. An arrangement for smoothing and compacting a weld on a cylindrical support sleeve includes, the abutment on which the support sleeve may be mounted, the device, and the roller.

Abstract: In an impact rolling apparatus the axes of roller heads are arranged substantially perpendicularly relative to the longitudinal axis of the workpiece. Accordingly, a displacing of the material at the workpiece proceeds predominantly tangentially perpendicularly to the longitudinal axis of the workpiece, caused by the impact effect of the impact rollers mounted at the roller heads. By this arrangement of the roller heads impact rolling operations can be performed close to a shoulder of the workpiece and marked steps thus maintaining the advantages over the known impact rolling method at which the displacement of the material proceeds predominantly in the direction of the longitudinal axis of the workpiece.

Abstract: According to the well known Grob method, there is fabricated on a mandrel provided with outer or external toothing or teeth a substantially dished or pot-shaped hollow body with corresponding inner or internal toothing or teeth. This fabrication operation starts with a blank comprising an at least partial web portion or dish base and a rim portion or dish rim projecting in a substantially tube-like or tubular configuration from the web portion or dish base. As seen in longitudinal section, this blank possesses a rounded or arcuate portion in the transition region or zone between the rim portion or dish rim and the web portion or dish base. This rounded or arcuate portion has a mean radius of curvature which is at least as large as the wall thickness of the rim portion or dish rim of the blank.

Abstract: A machine for removing the internal bead of longitudinal seam welded tubing by flattening includes a mandrel to be positioned within the tubing, an external hammer which includes a vertically oscillating roller which hammers the outside of the tubing opposite the weld so as to force the mandrel against the bead to flatten it and a second roller which serves as an anvil to restrain and shape the external surface of the tube including the weld to prevent the tubing from being deformed.

Abstract: An improved process and apparatus for continuous production of welded tubes is disclosed wherein a metal strip material is formed into a tubular form, the longitudinal edges thereof welded, and the welded seam cold worked by the application of a high frequency pulsating force to each area of the seam, while it is supported and widened from within.

Abstract: An apparatus for flattening the weld bead of longitudinally welded tubes consisting of a hammering mass impacting with a frequency greater than 2500 impacts per minute and an anvil having an elastomer bushing at each end.