Mannesmann Aktiengesellschaft

Mannesmannrohren-Werke Ag

V&m Deutschland Gmbh

Salzgitter Mannesmann Line Pipe Gmbh

Vallourec Deutshcland Gmbh

Mannesmann Fuchs Rohr Gmbh

Mannesmannröhren

Mannesmann Line Pipe Gmbh

Salzgitter Mannesmann Forschung Gmbh

Alfred Graff

Gert Fischer

Friedhelm Schlawne

Michael Wachter

Ashraf Koka

Hans-Jurgen Rohde

Stefan Nitsche

Michael Kaack

Wolfgang Bottger

Till Schmitte

Hans-Joachim Rath

Rainer Lücke

Sven Gwildies

Jürgen Verhoeven

Thomas Kersting

Ludwig Oesterlein

Jochen Berkemeier

Karl-Heinz Breckel

Axel Heinz

Karsten Deegen

A leakage flux probe for non-destructive leakage flux-testing of magnetizable 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.

Leakage flux probe for non-destructive leakage flux-testing of bodies consisting of magnetisable material

The invention relates to an ultrasonic probe for the non-destructive testing of metal work pieces, particularly pipes, for transverse defects, comprising a row-shaped arrangement of oscillator elements located on a lead wedge for coupling to the work piece. According to the invention, the lead wedge is designed as a wedge-shaped hollow body, which is filled with fluid and the wedge angle of which is a maximum of 24, and which is arranged on the work piece such that the intromission angle into the work piece is a maximum of 70.

Ultrasonic probe

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.

Device for nondestructive testing of pipes

The present invention pertains to a device for ultrasonic inspection of a weld seam of a longitudinally welded pipe for longitudinal defects with an inspection unit, which is relatively displaceable on a pipe surface on at least one side of the weld seam. The device also has two inspection heads in a tandem and spatially-variable arrangement, such that they can be positioned relative to the pipe surface to correspond to an intended acoustic irradiation angle independent of the diameter of the pipe. According to the invention, one inspection head acts as a transmitter and the other inspection head acts as a receiver. The device also has a pick-up connected to each of the two inspection heads, a coupling means connection connected to each pick-up, and a replaceable connecting element connected each pick-up via the coupling means connection.

Device for the ultrasonic inspection of the weld seam of longitudinally welded pipes for defects

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.

Device for ultrasonic weld seam testing of longitudinally welded pipes for longitudinal and transversal errors

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+&#x394;X, wherein &#x394;X is a multiple of a shot distance, and the difference is evaluated.

Method of detecting discontinuities on elongated workpieces

An electrodynamic ultrasonic transducer includes a housing to be placed against a workpiece surface to be tested. A magnet system is arranged in the housing in the vicinity of the workpiece surface to be tested. A transducer coil system is arranged between the magnet system and the workpiece surface. The housing is of a non-magnetic, electrically conducting material, and the housing wall has, in a region receiving the magnet system, segment-like recesses. Circuit closing plates are removably mounted in the recesses for ensuring a magnetic flux between the workpiece surface and the magnet system.

Modifiable electrodynamic ultrasonic transducer

An electrodynamic permanent magnet transducer for the non-destructive testing of workpieces by means of ultrasound. A soft magnetic housing is preferably provided in magnetically conducting contact with a pole surface of the permanent magnet to provide a compact magnetic return path for the magnetic field created by the permanent magnet. A hollow cylindrical body of nonmagnetic material is disposed to contactingly surround the permanent magnet to substantially eliminate magnetic short circuits parallel to the pole axis of the permanent magnet. The provision of two spiral transducer coils allows for the transmission and reception of ultrasound in a single permanent magnet transducer.

Electrodynamic permanent magnet transducer

An electrodynamic ultrasonic transducer, for testing a workpiece, has a pair of spaced permanent magnets, a transducer coil, a concentrator, and a non-ferromagnetic member which partially surrounds the concentrator. In order to concentrate the magnetic lines of flux, the concentrator has a cross-sectional area which is smaller than the cross-sectional area of the adjacent permanent magnets. A transducer coil is acted on by a high frequency transmission pulse, whereby ultrasonics is produced in the workpiece to be tested.

Electrodynamic ultrasonic transducer

The invention furnishes an electrodynamic transducer head for a non-destructive testing of workpieces with electrically conductive surfaces by way of ultrasound. A magnet system is employed for generating of a static or a low-frequency magnet field, and at least one transducer coil is disposed at the front face of the magnet system disposed toward the workpiece. The transducer coil is furnished on the side toward the workpiece with a wear-resistant layer, and the transducer coil exhibits between itself and this front face of the magnet system an intermediate part with an insulating layer, which is solidly connected with the front face and with the coil adjoining at the insulating layer. The invention discloses production of a transducer coil, in a way which is simple and economical and results in a transducer head which can be universally employed, and where the eddy current formations, resulting in interfering signals, and the mechanical vibrations, both in the transducer coil as well as in the magnet system, are substantially suppressed or, respectively, damped. The intermediate part (10) comprises at least two layers (11, 12), where one of the layers (12) is electrically conductive and which layer ( 12) is made of a material thickness which is larger than the skin depth for a given high-frequency field.

Growing community of inventors

Essen, Germany

Alfred Graff