Abstract: In a method and apparatus for making welded large pipes, a leading end of a hot strip is connected to a trailing end of a leader strip and then subjected to a two-stage leveling for strip flatness in transverse direction and strip flatness in longitudinal direction. The entire surface of the hot strip including strip edges thereof is inspected by ultrasound and the strip edges are prepared in four stages before being pre-bent. The hot strip is then shaped into a slotted tube and the strip edges are welded along the inner and outer sides by laser to produce the pipe. Online process diagnostic is provided for monitoring the welding step and the finished welded pipe diameter is measured through online measurement. Online determination of a profile of a welded seam configuration and computer tomographic determination and evaluation of flaws inside the pipe, as well as ultrasonic inspection of the welded seam are further provided.

Abstract: A device for ultrasonic weld seam testing of longitudinally includes two testing carriages swingably suspended and moveable on the pipe surface to the right and left of the weld seam for longitudinal flaw inspection, and one testing carriage swingably suspended in central relationship to the weld seam and moveable on the pipe surface for transverse flaw inspection. Each testing carriage has a mount for accommodating at least one testing head which includes an oscillator, and at least one coupling medium connection having a channel ending in the region of the oscillator and configured as nozzle in the outlet area. The test head for longitudinal flaw inspection can be arranged at various fixed and predefined angle positions at variable distance to the nozzle in the mount, and the test head for transverse flaw inspection can be arranged, together with the mount, at a variable distance to the pipe surface in a support element accommodating the mount.

Abstract: A device for deburring the inside of a longitudinally seam-welded pipe includes a retention arm secured outside the pipe in the area of the pipe that is not yet closed and having an end zone which is located behind the welding spot. Arranged on the retention arm is a frame part which is tiltable in longitudinal direction of the pipe about a tilt axis and provided with a scraping tool. The tilt axis of the frame part is hereby located, as viewed in advancing direction, behind the scraping point at the end of the frame part. An adjustment mechanism is provided on the forward end of the frame part for adjusting the tilt angle.

Abstract: A metallurgical vessel for transporting molten metals with a metal jacket with a heat-resistant lining is disclosed. The jacket has two reinforcing rings extending in the peripheral direction and being secured to and integrated in the jacket. The vessel also has two one-part shield segments, each affixed to at least to one of two stiffening rings. The shield segments include arms that extend in both peripheral directions and are provided with a welding edge for welding to the stiffening rings. Two lifting lugs are disposed on the exterior of the vessel on opposing sides thereof and supported by the stiffening rings. A stiffening ring can be implemented as two 120° segments connected at their ends to the two shield segments which each extend over 60° along the periphery.

Abstract: In a method of detecting discontinuities on elongated workpieces, in particular tubes and bars, using ultrasonic testing system, a test object is positioned in relationship to a test head of the testing system, with the test object and the test head being moveable to one another. Signals from the test head are transmitted to an evaluation unit, where they are digitized and evaluated. The digitized signals of a test shot of a length position X are compared with digitized signals of a test shot of a length position X+?X, wherein ?X is a multiple of a shot distance, and the difference is evaluated.

Abstract: In a process for producing welded steel pipes, a pipe is molded cold from a TM-rolled sheet, welded together and sized to the desired diameter, whereby the sheet includes steel with (in wt. %) 0.02 to 0.20% carbon, 0.05 to 0.50% silicon, 0.50 to 2.50% manganese, 0.003 to 0.06% aluminum, the remainder being iron with potentially other production-related impurities. After welding and sizing, the pipe is subjected to a heat treatment process at a temperature of 100-300° C. and for a holding time that is suited to the thickness of the pipe wall, with subsequent cooling with air or by forced cooling. The resulting pipe is resistant to aging and has sufficiently integral deformation reserve against fracturing with the same high degree of strength, without exceeding the upper limit for the ratio of yield strength to tensile stress according to the current industry standards for conventional steels.

Abstract: The invention relates to a vessel for metallurgical purposes intended for transporting molten metals. The tank has a metal jacket provided with a heat-proof lining. Two lifting lugs are disposed on the outer side opposite one another, each of which is supported by a lug shield connected to the metal jacket. The lug shield is disposed so as to limit movement in vertical and peripheral direction. Alternatively, the vessel can be made of sections of pipe, with the lug shield connected to a reinforcement ring on the pipe sections. Means are fixed on the metal jacket and/or the reinforcement ring(s) for receiving the own weight of the lug shield and the vessel when the vessel is in a vertical or tilted position.

Abstract: A blast tuyere for shaft furnaces, includes a conical hollow main body having inner and outer casings defining a hollow space and interconnected by a tuyere nose. The outer casing is formed by a single-piece base body terminating smoothly in the tuyere nose, and the inner casing is formed by a conical weld-in part. The hollow space is divided in antechamber, adjacent the tuyere nose, and main chamber, completely separated hydraulically and including separate coolant circuits. The coolant circuit for the antechamber includes two parallel passages for supply and return of coolant. The passages terminate in a ring channel, arranged in the tuyere nose in a direction transversely to the passages, and are located in an area of an upper apex of the main body radially outside the main chamber. The coolant circuit for the main chamber includes a helical cooling passageway whose inner wall is formed by the weld-in part.