Abstract: In a method of rolling tubes in a stretch-reducing rolling mill having a group drive in which the elongation, and therefore the tension is increased by increasing the speed of an auxiliary drive motor relative to that of a main drive motor, the length of the trailing "thickened end", which must be rejected as scrap, is reduced by increasing the elongation from the point in time at which the start of the trailing end portion of the tube reaches the last stand. This trailing end portion is that portion which receives a larger wall thickness than the central portion of the tube as a result of the reduced tension exerted in the trailing end portion of prior art practices. The start of this trailing end portion can be predicted from experience or by rolling a sample tube without subjecting its trailing end portion to the said increased elongation and measuring the wall thickness at the trailing end portion of the sample tube.

Abstract: A rolling line for billets, bars, wire rod or the like, e.g. a roughing line has one or more rolling stands each having three or more driven rolls which are adjustable towards and away from the work material by a worm drive and a screw. The rolls are brought progressively closer together before each pass of the work material, whose cross section is thereby reduced with corresponding elongation. The direction of rotation of the rolls is reversed between each pass, unless two stands for rolling in opposite directions are provided in which case it is possible for the stands to be continuously driven but alternately operative. The work material is turned about its axis through half a roll pitch angle between each pass.

Abstract: A rolling mill and method for rolling material having a rectangular, oval or like elongated cross-sectional configuration into rod or wire, has a line of passes of which the first pass is formed by two rollers and the remaining passes are each formed by three rollers, and wherein the first pass deforms the material, whose input cross section has a ratio of the lengths of its major and minor principal axes greater than about 1:2 to an output cross section which is exactly round or a regular polygon, such as square or hexagonal or which deviates from such a geometrical configuration only to an extent such that the ratio of the lengths of the major and minor principal axes of the output cross section does not exceed about 1:2.

Abstract: In the reduction of the cross section of wire, rods or bars by rolling, the work material is placed under longitudinal compression in a roughing block and/or in an intermediate block and is only under tension in a finishing block. By this means, the ends of the work material are thinned prior to entry into the finishing block, instead of being thickened as they would be if the work material were under tension in the roughing and/or finishing block. Compensation for this end thinning is effected in the finishing block due to the rolling under tension, so that wastage due to cropped thickened ends is avoided.

Abstract: The stand-to-stand transmission ratios between the working sizing passes at the entry end of a rolling block for rolling bars, rods or wire are fixed but are different from one another. This enables an entire range of finished workpiece cross sections to be obtained from a given first pass workpiece entry cross-sectional area, merely by omitting one or more of the working stands and shifting other working stands from one location to another and by changing only the stands of the finishing sizing passes at the delivery end of the block.

Abstract: A rolling mill roll and method of rolling tubes is provided in which the roll has an annular concave working surface in the outer periphery, said surface having a central annular concave portion of a preselected arc and a pair of side edge annular concave portions on each side of said central portion, said side edge portions having an arc of greater radius than the central portion and thus of lesser curvature than the central portion.

Abstract: A method and apparatus are provided for the rolling of bars, rods or wire to avoid thickened ends in which a number of rolling stands are provided in tandem forming a rolling line and in which one or more of the last rolling stands in the line have separate drive means with means to regulate the speed independent of the other rolling stands to provide momentarily increased speed and tension on the two ends of the material being rolled.

Abstract: A rolling mill for rolling wire or rod product having a plurality of roll stands arranged one after the other, each having at least three driven rollers and in which the distance between at least two adjoining successive stands forming a group is not substantially greater than the roller diameter of the stands and the last sizing pass of each group of stands has a regular cross section in relation to the first sizing pass of the next following group.

Abstract: A process and mill for stretch reduction rolling of tubes is provided having individually driven roll stands, said roll strands being driven so as to impart a maximum traction force, limited only by the transferability of frictional forces between roll and tube, on the tube in all the passes that grip said tube, at least in the passes at the entry end of the mill.

Abstract: A multistand rolling mill for stretch reducing tubes is provided in which the first stands of a plurality of successive stands are operated to build up tension and at least one of said stands is provided with means for varying the roll speed to provide a desired speed step in those stands designed to build up tension.

Abstract: A sizing mill is provided for reducing tubes having a number of roll stands arranged one behind the other and in which the sizing pass of at least the first stand is so out of round that the first sizing pass can effect tube reduction over the whole range of external diameters of tubes to be rolled in any given rolling program.