Abstract: A cross-rolling mill for rolling a block over a mandrel forms a hollow block. It includes a plurality of working rollers, each of which exerts a substantially radially aligned rolling force onto the block. The working rollers are supported in a roll stand, and the gap between the working rollers and preferably also the alignment of the rolling axis of at least one of the working rollers relative to the block can be modified. Hydraulic actuators, preferably hydraulic capsules, are provided in order to modify the rolling gap and preferably also the alignment of the rolling axis of at least one of the working rollers relative to the block.

Abstract: A cross-rolling unit and a method for setting the roll pass of a cross-rolling unit, having at least two rolls and a roll housing, in which at least one of the rolls is mounted such that its position can be adjusted in order to change the roll pass, allow the roll pass to be adjusted by means of a roll-positioning apparatus even during rolling, which roll-positioning apparatus is characterized by a housing-connected part and a roller-mill-connected part, which can be moved relative to the housing-connected part during rolling, which parts can be repositioned relative to each other, and/or which roll-positioning apparatus characterized by a drive which is dimensioned in such a way that rolling forces can be applied.

Abstract: An apparatus for measuring a thread includes a holder for detachably holding a tube having a thread formed at an end of the tube. A first optical measuring section having an optical sensor is attached to a manipulator in order to move the measuring section relative to the tube. The optical measuring section is adjustably tiltable about a first adjusting axis relative to a thread axis of the thread. A second optical measuring section having a second optical sensor is arranged at the manipulator, wherein the optical measuring sections collectively form a measuring channel to provide simultaneous measurement of opposite sides of the thread of the tube.

Abstract: A cross-rolling mill for rolling a block over a mandrel forms a hollow block. It includes a plurality of working rollers, each of which exerts a substantially radially aligned rolling force onto the block. The working rollers are supported in a roll stand, and the gap between the working rollers and preferably also the alignment of the rolling axis of at least one of the working rollers relative to the block can be modified. Hydraulic actuators, preferably hydraulic capsules, are provided in order to modify the rolling gap and preferably also the alignment of the rolling axis of at least one of the working rollers relative to the block.

Abstract: The invention relates to an apparatus for measuring a thread (1), comprising a holder for detachably holding a tube (2), wherein the thread (1) is formed at one end of the tube (2), a first optical measuring section (5) having an optical sensor (5a), wherein the optical measuring section (5) is attached to a manipulator (3) in order to move the measuring section (5) relative to the tube (2), and wherein the optical measuring section (5) is adjustably tiltable about a first adjusting axis (S1) relative to a thread axis (A) of the thread (1), wherein a second optical measuring section (5) having a second optical sensor (5a) is arranged at the manipulator (3), wherein the optical measuring sections (5) overall form a measuring channel (4) for simultaneous measurement of opposite sides of the thread (1).

Abstract: An apparatus for making a cold-pilger-rolled tube has two grooved pilger rolls rotatable about respective axes to compress a workpiece moving in a travel direction against a mandrel extending in the direction between a nip formed between the rolls and anchored upstream of the nip in a thrust block. Workpiece thickness is adjusted on the fly by measuring a wall thickness of the workpiece downstream in the direction from the roll as the workpiece passes through the nip and for displacing the thrust block and mandrel in to the travel direction as the workpiece passes through the nip in accordance with the measured wall thickness.

Abstract: An apparatus for making a cold-pilger-rolled tube has two grooved pilger rolls rotatable about respective axes to compress a workpiece moving in a travel direction against a mandrel extending in the direction between a nip formed between the rolls and anchored upstream of the nip in a thrust block. Workpiece thickness is adjusted on the fly by measuring a wall thickness of the workpiece downstream in the direction from the roll as the workpiece passes through the nip and for displacing the thrust block and mandrel in to the travel direction as the workpiece passes through the nip in accordance with the measured wall thickness.

Abstract: In order to make available a contact-free pipe wall thickness measurement device having a simple design, having at least two laser ultrasound measurement heads, it is possible to dispose at least two ultrasound measurement heads on a common pivot frame in the contact-free pipe wall thickness measurement device, which frame can pivot about a pivot axis.

Abstract: Quality of a wire or rod is controlled in a rolling mill having a succession of roll stands spaced apart in a workpiece-travel direction by a method having the first step of, before rolling a wire or rod, statically measuring a sample of at least one wire or rod with typical real roll flaws and storing the flaw data in standard format in a control computer. A single cross-sectional shape or, if there is noise, an average of a plurality of averaged cross-sectional shapes are stored standardized as polar coordinates. During actual rolling of a wire or rod its actual-shape is continuously measured and actual-shape data is generated. A similarity analysis is continuously effected by comparing the flaw data in standard format with the actual-shape data of the wire or rod being rolled. When the actual cross-sectional shape data corresponds to the flaw data, an alarm is generated.

Abstract: A method and device for measuring the wall thickness of a pipe in a pipe-rolling mill wherein a Fabry-Pérot interfero-meter has its mirror spacing set by providing an input to a linear activity for one of the mirrors from a controller receiving an input from a photodiode at the output side of the interferometer. A second control circuit regulates the amplification of that photodiode with at least one parameter derived from the rolling system, for example, the input optical signal to the interferometer or a disturbance value representing for example the temperature of the rolled product and obtained through an optical pyrometer. The incoming optical signal may be tapped to another photodiode also with a variable amplification amplifier and both amplifiers may be controlled by a second controller.

Abstract: The eccentricity of a hollow billet is measured at the outlet of an inclined-roll rolling mill by launching an ultrasonic pulse into the billet from a laser of a measuring device and measuring the transit time of an echo pulse also utilizing a laser and an optical analyzer. The measuring device is moved, during travel of the hollow billet along a path from the rolling mill linearly into the direction of travel or angularly around the hollow billet to eliminate the effect of the internal helical formation of the eccentricity on the measurements. The wall thickness measurements are evaluated by a computer and subjected to Fourier analysis.

Abstract: A method and device for measuring the wall thickness of a pipe in a pipe-rolling mill wherein a Fabry-Pérot interfero-meter has its mirror spacing set by providing an input to a linear activity for one of the mirrors from a controller receiving an input from a photodiode at the output side of the interferometer. A second control circuit regulates the amplification of that photodiode with at least one parameter derived from the rolling system, for example, the input optical signal to the interferometer or a disturbance value representing for example the temperature of the rolled product and obtained through an optical pyrometer. The incoming optical signal may be tapped to another photodiode also with a variable amplification amplifier and both amplifiers may be controlled by a second controller.

Abstract: The speed of sound c is determined in a material as a function of the temperature T by heating an end of an elongated sample body of the material of the temperature and determining the time difference for the receipt of echoes from two reflective zones at the heated end. The opposite end of the body is cooled in a water bath which can couple an ultrasonic test head to the body.

Abstract: A method of determining eccentricity of a hollow billet in the course of rolling in seamless tubing or seamless pipe manufacture whereby at the outlet side of an inclined roll mill at least one measurement head is provided for ultrasonic wall thickness measurement and the results of a number of measurements are processed by Fast Fourier Transform analysis series elements which approximate the eccentricity as a result of the helical or spiral superimposition of an eccentricity amplitude on the mean eccentricity in terms of the wall thickness of the hollow billet.

Abstract: The eccentricity of a hollow billet is measured at the outlet of an inclined-roll rolling mill by launching an ultrasonic pulse into the billet from a laser of a measuring device and measuring the transit time of an echo pulse also utilizing a laser and an optical analyzer. The measuring device is moved, during travel of the hollow billet along a path from the rolling mill linearly into the direction of travel or angularly around the hollow billet to eliminate the effect of the internal helical formation of the eccentricity on the measurements. The wall thickness measurements are evaluated by a computer and subjected to Fourier analysis.

Abstract: In a method for contactless online measuring of the wall thickness of hot-rolled pipes in the hot state for determining undesirable inner wall structures, at least one measuring head, operating according to the laser ultrasound method, scans a segment of a wall of a pipe to be measured in a circumferential direction during or directly after a rolling process. The course of the wall of a cross-section of the pipe is then reconstructed with a computer. The measuring head is a compact laser ultrasound measuring head adjustable relative to the pipe dimension to be measured. It has an excitation laser and an illumination laser and optical elements for collecting a carrier light containing the ultrasound signal and reflected at a surface of the pipe. The excitation and illumination lasers and the optical elements are arranged in a common housing of the measuring head. A pivot device is provided to pivot the laser ultrasound measuring head across a segment of the pipe in the circumferential direction.

Abstract: The speed of sound c is determined in a material as a function of the temperature T by heating an end of an elongated sample body of the material of the temperature and determining the time difference for the receipt of echoes from two reflective zones at the heated end. The opposite end of the body is cooled in a water bath which can couple an ultrasonic test head to the body.