Mannesmann Aktiengesellschaft

Sms Demag Ag

Sms Meer Gmbh

Wean United, Inc.

Mannesmann Aktiengesellshcaft

Horst Stinnertz

Michael Baensch

Josef Gerretz

Peter Kalkenings

Wolfgang Reichelt

Peter Voss-Spilker

Klaus Rehag

Karl H Hausler

Karl-Heinz Haeusler

Jurgen Schmidt

The invention concerns a drive system () for a rolling mill, especially for a cold pilger rolling mill with at least one roll frame () movable back and forth, at least one crank drive () which has a crank arm () with a counterweight () for at least partial compensation of the inertial forces produced by the mill frame (), a drive () and a connecting rod () which articulates the mill frame () and the crank arm () with one another and at least one counterweight () which is eccentrically rotatable and serves to compensate the inertial forces and/or the moments of inertia. To achieve an efficient balancing of the inertial forces with a simple construction of the drive system, the invention provides that at least one counterweight () is rotatably driven by a separate rod () independently from the drive () of the crank drive.

Drive system for a rolling mill

A cold pilger rolling tool for producing internally ribbed tubes uses a cold pilger step rolling process in a rolling stand that is movable back and forth in a direction of rolling and has rolls of a tapered design. The rolls of the stand roll along a material with an alternating direction of rotation. The tool includes a cold pilger rolling mandrel which tapers. The tool further comprises an extension plug mounted coaxially and rotatably at a free end of the cold pilger rolling mandrel and in which a negative of the helical internal ribbing which is to be produced is machined.

Cold pilger rolling tool for producing internally ribbed tubes

Disclosed is a process and apparatus for producing metal-sheathed strands, especially glass fiber cables, from a metal strip that is first formed into a U-shaped profile and then, after the placement therein of a non-ductile or slightly ductile core material, is closed to form a split tube carrying and/or protecting the core material, which split tube, after the welding of its longitudinal seam, is reduced in a subsequent deformation step. In the process of the invention, the metal-sheathed strand with the welded longitudinal seam is cold-formed in a stretch-reducing fashion in multiple continuous sequential steps. In the apparatus for implementing the process, multiple speed-controlled roll stands of a stretch-reducing cold rolling mill with declining caliber cross-sections are arranged one behind the other directly after the longitudinal seam welding machine for the split tube for the reductive deformation of the metal sheath.

Process for producing metal-sheathed strands, especially glass fiber

A method and apparatus for continuously feeding rolling stock through a cold pilger rolling mill. A rolling stock--either a continuous or so-called 'endless' piece, or a plurality of serially fed, spaced-apart pieces--is initially fed into a roll stand by a feed side drive or transporting arrangement, and thereafter, drawn through the rolling mill by a delivery side drive or transporting arrangement that is located in a rolling direction, i.e. downstream, from the feed side drive arrangement. Once the leading free end of the rolling stock is grasped by the delivery side transporting arrangement, the feed side transporting arrangement ceases to feed the rolling stock through the rolling mill, i.e. forward feeding of the rolling stock is exclusively controlled by the delivery side transporting arrangement. Thus, the critical compressive stresses and/or buckling stresses typically experienced by the rolling stock as a result of pushing the stock through the rolling mill are prevented and the disruptions in the rolling process caused by these stresses are accordingly also prevented. The transporting arrangements are operable independent of each other and at transporting or rolling speeds dependent upon each other.

Method and apparatus for cold rolling tubes

Disclosed are a method and apparatus for manufacturing tubes, preferably tubes composed of high-tensile steels or special alloys, using the cold pilger rolling method with two rolling stands which can be moved backward and forward, at least in opposite directions at times and in the rolling direction by means of crank drives. The rolling stands have rollers which are calibrated in a tapering manner and which, driven by toothed racks via cogs, roll over the material to be rolled, with an alternating rotation direction. The majority of the forming work takes place on the first rolling stand and a relatively small portion of the forming work takes place on the second rolling stand and additional smoothing work is carried out. Reduction rolling takes place in both rolling stands via a mandrel which is matched to the roller caliber, and the backward and forward movements of the two rolling stands are matched to one another in such a manner that the angular offset between the crank drives is chosen such that the forming zone of the first stand does not occur at the same time as the forming zone of the second stand.

Method for manufacturing tubes using the cold pilger rolling method

A process for rolling tubes, in which two grooved rolls mounted opposite one another in a roll stand are moved back and forth, i.e., reciprocated, on tube-shaped rolling material, which is arranged on a tapered rolling mandrel supported in the axial direction by a mandrel bar. The rotary-driven rolls have, on their circumferential surfaces, narrowing work grooves matching in shape to the tapered rolling mandrel, which roll down the rolling material on the rolling mandrel. At the ends of the work passes the rolls release the rolling material at the two dead centers of the roll stand path so as to assist in the advancement and rotation of the rolling material. According to the invention, the tube-shaped rolling material and the rolling mandrel are driven asynchronously in the same rotational direction at different rotational speeds.

Process for rolling tubes

A process for drawing stretched metal workpieces, especially tubes, for the purpose of cross-sectional reduction in more than one drawing step using at least two sequential drawing aggregates. The aggregates grip the workpiece on the outer periphery, with two alternately-moved clamping carriages, which draw the workpiece continuously through respective drawing rings associated with the respective aggregates and arranged in respective drawing-ring holders. The drawing aggregates can be driven independently of one another in a power-regulated and/or moment-regulated manner. Furthermore, during the drawing process, a defined prestress force, which prevents deflection of the workpieces from a straight line, is maintained at all times in the section of the workpiece located between the drawing aggregates.

Process and device for straight-drawing long drawing material in

A method of making tubing includes cold pilgrim step rolling wherein particularly a frame moves back and fourth carrying tapering rolls which roll in alternating directions upon the stock to be rolled whereby in addition a cylindrical mandrel is provided as well as turning and advancing facilities for the tube or pipe to be made and with further utilization of a rotatably driven clamping and holding device downstream for extracting the tubes or pipes being made.

Cold pilgrim rolling

A method of pilgrim step rolling of elongated stock includes reciprocating a roll stand or frame for moving the stock either by rotating it and/or advancing it; such a method is improved by providing a first component of movement at a constant speed and adding thereto, near each dead center portion of the reciprocating frame movement, a second component of motion including temporary accelerating and decelerating periods.

Method of pilgrim step rolling

A method and apparatus for manufacturing seamless metal tubes by the cold pilger process permitting the continuous feeding of fresh cooling and lubricating agent between the mandrel and inner surface of the material being rolled. The apparatus includes a roll stand including tapering calibrated rolls (2) which is reciprocatingly movable in the direction of rolling at a predetermined stroke to define a reduction zone, the rolls (2) rolling with alternating direction of rotation over the material (3) being rolled and a tapering mandrel (1) inside the material for reducing the diameter and wall thickness of the material, wherein at least one of the rolls (2) and the mandrel (1) has a surface discontinuity within the reduction zone for creating a zone of interruption (6) or an annular gap within which no contact occurs between the material to be rolled (3) and the mandrel (1).

Method and apparatus for lubricating the mandrel upon the manufacture of

Molten metal is sprayed onto a rotational mandrel which oscillates axially and an axial translatory extraction motion is superimposed for removing the built-up hollow from the mandrel.

Making a hollow of rotational symmetry

The disclosure of the present invention relates to a compensating counterweight system used in a cold pilger step-by-step type seamless tube rolling mill reciprocated by a crank assembly. The crank assembly includes first and second compensating mass devices which are arranged to rotate coaxially on a single crank shaft in opposite directions relative to each other. The two mass devices are kinetically connected through a bevel gear drive set which causes the second compensating mass device to rotate in an opposite directon to the first compensating mass device.

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Willich, Germany

Horst Stinnertz