Abstract: The invention relates to a connection arrangement of hollow steel sections as support elements which are interconnected using a joint connection, the connection being subject to axial pressure. According to the invention, the joint connection is designed as a detachable, form-fitting plug-in connection.

Abstract: The invention relates to a method for producing seamless tubes from metal, particularly from steel, wherein a previously produced hot hollow block is stretched by means of a three-roll bar rolling mill on a mandrel to form a parent tube and, before running into the bar rolling mill, the hollow block is provided with a rolling step that makes the diameter more uniform by means of an upstream stand. It is in this case provided that the rolls of the upstream stand are moved apart and together to the same extent as the deforming stands of the bar rolling mill, wherein the calibrating base radius of the rolls of the upstream stand extends over 60° and this is followed by a flank radius with a tangential transition which is dimensioned such that even with the maximum setting of the rolls in the region of the flank there is virtually no diameter reduction of the largest hollow block diameter to be expected.

Abstract: An array of ultrasonic transducers in a conical formation emits pulses of ultrasonic simultaneously so that an anomaly of any orientation in a test object can be detected efficiently.

Abstract: The invention relates to a traction rod (1) for bracing a crane jib, comprising a metallic tubular body (2) and coupling elements (3) which are connected to both ends thereof for an articulated connection of the traction rods among each other by means of bolts (5). According to the invention, the tubular body and the coupling elements consist of a one-piece tube portion, wherein the coupling elements are designed in each case as a thicker zone of the wall of the ends of the tubular body and are dimensioned in such a manner that a weakening of the cross section of the nominal wall thickness of the coupling elements, which has to be considered for calculating the load capacity of the tubular body, is prevented in the region of the bolt connection and the transition regions (7) from the respective thicker zones of the wall in the direction of the tubular body have a transition free of starting points for increasing fatigue strength.

Abstract: In a method for producing seamless pipes, a hot hollow block created previously in a piercing mill is stretched by means of a continuous rolling mill on a mandrel bar to form a parent pipe and the parent pipe is fed directly to a stretch reducing mill or sizing mill as a finishing mill, while forgoing an extracting mill and a reheating furnace, and is rolled there to the required final pipe diameter. The hollow block is pre-dimensioned in its length in such a manner that only a single length is produced as the required parent pipe length during the stretching in the continuous rolling mill and the parent pipe is pulled off of the mandrel rod by the finishing rolling during the subsequent finishing rolling, wherein the rolling is performed using rolling mill components that are designed in the dimensions thereof for handling single lengths.

Abstract: In a method for the nondestructive testing of pipes made of ferromagnetic steel for flaws by means of stray flux, the pipe is magnetized by a constant field and the discontinuities in the near-surface region of the outer or inner surface of the pipe cause magnetic stray fluxes, which exit the pipe surface and are detected by probes of a test unit, wherein the association of the detected amplitude signals is performed on the basis of the amplitude height and/or the frequency spectrum with respect to an external or internal flaw via defined flaw thresholds respectively. For this, prior to associating the detected amplitude signals to an external or internal flaw, the angular position of the flaw relative to the respective magnetic field direction is determined, and a correction of the signals is carried out via a previously determined correction factor for amplitudes and/or frequencies of a perpendicular angular position.

Abstract: The invention relates to a process for the destruction-free testing of metallic pipes, in particular seamlessly produced steel pipes, in which method the entire length of the pipe is scanned following the circumference precisely and in this case, in addition to the wall thickness (WD) and the external diameter (Da) being determined, the inner and outer surfaces of the pipe are examined for faults, the faults determined in this process are compared with a predefined permissible reference fault depth RFT (RFT=fault threshold of×% of the nominal wall thickness), the pipes are sent to reworking means if the fault threshold is exceeded, and a requisite minimum wall thickness (WDmin) has to be present in the reworked region after the processing has been carried out.

Abstract: A method for monitoring the manufacturing process of hot-rolled tubes in which the type and dimensional characteristics of structures produced by the rolling process on an outer surface of the tube are evaluated to assess the process state. Immediately subsequent to the rolling process in the exit side region of a rolling stand the outer surface of at least one defined portion of the tube is detected by measuring technology, linearly by means of an optical laser stripe method and in a clocked manner in the form of profile lines, and the profile lines are then combined to form an at least two-dimensional topography and the topography is evaluated to assess the process state.

Abstract: The invention relates to a connection arrangement of hollow steel sections as support elements which are interconnected using a joint connection, the connection being subject to axial pressure. According to the invention, the joint connection is designed as a detachable, form-fitting plug-in connection.

Abstract: A leakage flux probe for non-destructive leakage flux-testing of bodies consisting of magnetizable material, in particular of pipes consisting of ferromagnetic steel, having a plurality of sensors disposed one behind the other in a straight line for detection of near-surface flaws in the body. In order to create a leakage flux probe for non-destructive leakage flux-testing of bodies consisting of magnetizable material, in particular of pipes consisting of ferromagnetic steel, which in a main testing direction has a broadened directional characteristic. At least two similar sensors are disposed and interconnected in a sensor package in a different angular orientation with respect to the main testing direction one above the other, one next to the other or one lying inside the other. The sensor packages disposed generally in a line one behind the other can be influenced individually by the generated leakage flux of an existing flaw.

Abstract: A leakage flux probe for non-destructive leakage flux-testing of magnetisable bodies comprising a plurality of coils for detection of near-surface flaws in the body, wherein the coils have a degree of sensitivity which is dependent upon the orientation of the flaws in the body, and wherein coils having a different degree of sensitivity are disposed in the leakage flux probe with a first type of coil having a high degree of sensitivity for longitudinal flaws or transverse flaws and a second type of coil having a high degree of sensitivity for oblique flaws.

Abstract: The invention relates to a method for the individual tracking of metallic hollow bodies, in particular hot-fabricated steel tubes, wherein following a final step of hot-work the individual tube is provided with a distinctive identification on the tube circumference, which is read in the feed region to the subsequent manufacturing or test stations automatically as a video image during transport and independently from the direction of transport. According to the invention, the labeling of the tube circumference is carried out in at least two segment-like sections, the tube circumference being divided, wherein the labeling is carried out in segments with a rotation of less than 360 DEG of the numbering unit and the segments comprise an axial offset relative to the longitudinal axis of the tube, which is greater than the width of the data matrix code.

Abstract: The invention relates to a method for connecting thick-walled metal workpieces by welding. In order to create the weld joint, the cross-sections are provided with a maximum of three weld regions according to wall thickness, the welding being carried out by a combined use of welding methods: the first weld region (root) is welded by means of laser beam welding or hybrid laser-arc welding, the second weld region is welded by means of hybrid laser-arc welding, and the third weld region required occasionally depending on the thickness of the sheet metal is welded by means of hybrid laser-arc welding or simply arc welding. The invention also relates to a seam preparation corresponding to the respective welding method used.

Abstract: The invention relates to a method and device for optically measuring external thread profiles, particularly at the ends of pipes, wherein the thread is previously synchronously produced in a production line and is continuously measured in line from start to finish of the thread prior to further processing. The aim of the invention is to allow cost-effective inspection of the thread during synchronous production of the thread.

Abstract: A device for nondestructive testing of a pipe made of ferromagnetic steel for detection of longitudinal, transverse or inclined flaws using magnetic or magnetic-induction test procedures is disclosed. The device includes a magnetizing yoke which transmits the magnetic flux contactless into the pipe and at least two magnetic-field-sensitive scanning probes having GMR sensors. The GMR sensors are combined into sensor groups in form of a sensor array and electrically connected in parallel. A single preamplifier connected to each sensor group in one-to-one correspondence. The device further includes an evaluation unit.

Abstract: The invention relates to an apparatus for making a seamless hollow body (10) from a solid round block (7) of steel with a diameter <95% of the diameter of the solid round block by means of a two-roll cross-rolling mill with a piercing mandrel (3) held between the inclined roll (1) and including a piercer (5) and at least one smoothing part (4) using pass-closing guides, or by means of a three-roll cross rolling mill with a piercing mandrel held between the inclined rolls and including a piercer and at least one smoothing part, wherein the distance of the rolls is adjusted in a particular manner at the narrowest cross-section (2) in relation to the diameter of the used round block, and the position of the piercing mandrel is adjusted in relation to the narrowest cross-section of the rollers.

Abstract: A device for the optimized circulation of mandrels includes a presentation and/or cooling table for mandrel rods, a lubricating station for the mandrel rods, optionally an additional drying station for the lubricant applied to the mandrels, and associated roller conveyors. An additional secondary rod circulation of is arranged upstream of the standard rod circulation and includes two redundantly operating transfer tables connected to the presentation and/or cooling table by a third roller conveyor or the first roller conveyor for the discharge of no longer needed rods from the standard rod circulation. The third roller conveyor either forms the continuation of the first roller conveyor or is arranged parallel thereto with an offset. A fourth roller conveyor for accommodating mandrel rods or passing mandrel rods intermittently into the standard circulation via an intermediate buffer is arranged on the opposite side of the transfer tables parallel to the first roller conveyor.

Abstract: In a method for producing hot-rolled sections of steel with a rectangular or square cross-section, a substantially round pipe blank produced seamlessly by hot rolling or cold finished and welded and having a defined nominal outside diameter is initially produced and then formed at a forming temperature into a hollow section having the required cross-section, with visible edges C1 and C2 of the hollow section having a value ?1.5×t (t=wall thickness). The pipe blank has a nominal outer diameter determined from a reduction ratio of the pipe blank to be achieved and the hollow section dimensions to be achieved, wherein the reduction ration lies within a range of ?2% to ?13% and is determined according to the following formula: Reduction ratio R[%]=[(2×(H+B))??×D]×100%/[2×(H+B)].

Abstract: The invention relates to a method for filtering measurement signals by way of wavelet filtering, wherein the signals are first transferred to the wavelet domain by way of a wavelet transform, are subjected to threshold analysis, and the threshold values can then be varied in the wavelet domain commensurate with the respective measurement situation. The measurement signals are filtered by a plurality of filters arranged in segmentation levels and a statistical parameter is calculated based on an adjustable number of already calculated wavelet coefficients of a segmentation level and is then multiplied with a value that can be adjusted.

Abstract: The invention relates to a method for connecting the ends of steel tubes by means of orbital welding using a hybrid laser arc technique, with the tubes preferably having wall thicknesses ?6 mm and more particularly ?12 mm and diameters of preferably ?150 mm, the ends of which tubes are connected by one or more welding passes, wherein the laser and arc welding heads as tools are guided over a guide ring fixedly arranged around a tube end in the region of the weld site during the welding and are displaced around the tube diameter. The invention also relates to a device for carrying out the method, wherein the laser and the arc welding heads are positioned separately on the guide ring and are moved over the tube circumference and controlled independently of one another during the welding process.