Patents by Inventor Stefan Nitsche
Stefan Nitsche has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).
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Patent number: 9268884Abstract: A device for checkivng steel pipes during production and to a method using the device. The device includes a station for acquiring measurement data representative of physical measurements of the geometry of a pipe taken on an outside thereof, and a computer system configured to store template data applicable in a coordinate system and representative of overall geometry of a sizing body. In a chosen coordinate system, the system then provides a three-dimensional representation of parts of the pipe. For each part of the pipe, the system is referenced to determine a critical parameter, representative of the margin of passage of the sizing body inside a chosen part of the pipe. The method and device may thus establish a diagnostic of traversability of the pipe by a sizing body.Type: GrantFiled: May 30, 2011Date of Patent: February 23, 2016Assignee: V & M FRANCEInventors: Stefan Nitsche, Andreas Groos, Xiaoxing Guo, Nicolas Nourrit, Alejandra Segura
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Patent number: 8941376Abstract: The invention relates to a method for the automated measurement of the residual magnetic field strength of magnetized ferromagnetic workpieces, especially steel tubes, the residual magnetic field exiting the face of the tube end being measured by means of a measuring probe. Instead of directly measuring the residual field strength on the face, the curve of at least one magnetic field component is measured on the outer surface of the tube at least in the region of the tube ends and beyond the tube ends and the residual field strength on the face is inferred on the basis of the previously determined correlations between the residual field strength measured on the face and on the tube surface.Type: GrantFiled: November 18, 2009Date of Patent: January 27, 2015Assignee: Vallourec Deutschland GmbHInventors: Michael Kaack, Stefan Nitsche, André Germes
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Patent number: 8552718Abstract: 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.Type: GrantFiled: April 2, 2009Date of Patent: October 8, 2013Assignee: V & M Deutschland GmbHInventors: Andreas Groos, Stefan Nitsche
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Patent number: 8490492Abstract: 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.Type: GrantFiled: July 11, 2008Date of Patent: July 23, 2013Assignee: V & M Deutschland GmbHInventors: Andreas Groos, Stefan Nitsche
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Publication number: 20130131856Abstract: A device for checking steel pipes during production and to a method using the device. The device includes a station for acquiring measurement data representative of physical measurements of the geometry of a pipe taken on an outside thereof, and a computer system configured to store template data applicable in a coordinate system and representative of overall geometry of a sizing body. In a chosen coordinate system, the system then provides a three-dimensional representation of parts of the pipe. For each part of the pipe, the system is referenced to determine a critical parameter, representative of the margin of passage of the sizing body inside a chosen part of the pipe. The method and device may thus establish a diagnostic of traversability of the pipe by a sizing body.Type: ApplicationFiled: May 30, 2011Publication date: May 23, 2013Applicant: V & M FranceInventors: Stefan Nitsche, Andreas Groos, Xiaoxing Guo, Nicolas Nourrit, Alejandra Segura
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Patent number: 8344725Abstract: 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.Type: GrantFiled: February 24, 2010Date of Patent: January 1, 2013Assignee: V & M Deutschland GmbHInventors: Gert Fischer, Sven Gwildies, Michael Kaack, Alfred Graff, Ashraf Koka, Stefan Nitsche
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Publication number: 20120197594Abstract: 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.Type: ApplicationFiled: June 23, 2010Publication date: August 2, 2012Applicant: V & M Deutschland GMBHInventors: Thomas Orth, Stefan Nitsche, Till Schmitte, Klaus-Dieter Müller
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Patent number: 8224620Abstract: The invention relates to a method for testing the driftability of metal tubes, wherein a cylindrical drift body having a defined diameter and a defined length is guided through the tube with defined force for ensuring a predetermined internal diameter and a minimum straightness. Virtual drifting is hereby performed instead of the physical drift operation.Type: GrantFiled: November 27, 2009Date of Patent: July 17, 2012Assignee: V&M Deutschland GmbHInventors: Andreas Groos, Stefan Nitsche
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Publication number: 20120125111Abstract: 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.Type: ApplicationFiled: July 11, 2008Publication date: May 24, 2012Applicant: V & M Deutschland GmbHInventors: Andreas Groos, Stefan Nitsche
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Publication number: 20120098532Abstract: The invention relates to a method for the automated measurement of the residual magnetic field strength of magnetized ferromagnetic workpieces, especially steel tubes, the residual magnetic field exiting the face of the tube end being measured by means of a measuring probe. Instead of directly measuring the residual field strength on the face, the curve of at least one magnetic field component is measured on the outer surface of the tube at least in the region of the tube ends and beyond the tube ends and the residual field strength on the face is inferred on the basis of the previously determined correlations between the residual field strength measured on the face and on the tube surface.Type: ApplicationFiled: November 18, 2009Publication date: April 26, 2012Applicant: V & M DEUTSCHLAND GMBHInventors: Michael Kaack, Stefan Nitsche, André Germes
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Publication number: 20110268343Abstract: The invention relates to a method for the nondestructive testing of pipes made of ferromagnetic steel for flaws by means of stray flux, wherein the pipe is magnetized by a constant field and the discontinuities present 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 each for longitudinal and/or transversal flaw testing, 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.Type: ApplicationFiled: April 2, 2009Publication date: November 3, 2011Applicant: V & M DEUTSCHLAND GMBHInventors: Andreas Groos, Stefan Nitsche
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Publication number: 20110238369Abstract: The invention relates to a method for testing the driftability of metal tubes, wherein a cylindrical drift body having a defined diameter and a defined length is guided through the tube with defined force for ensuring a predetermined internal diameter and a minimum straightness. Virtual drifting is hereby performed instead of the physical drift operation.Type: ApplicationFiled: November 27, 2009Publication date: September 29, 2011Applicant: V & M Deutschland GmbHInventors: Andreas Groos, Stefan Nitsche
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Publication number: 20100219818Abstract: 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.Type: ApplicationFiled: February 24, 2010Publication date: September 2, 2010Applicant: V & M DEUTSCHLAND GMBHInventors: GERT FISCHER, Sven Gwildies, Michael Kaack, Alfred Graff, Ashraf Koka, Stefan Nitsche
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Patent number: 7779693Abstract: A method for nondestructive testing of the pipes for detecting surface flaws is disclosed. With of the method, flaws can be detected and analyzed in near-real-time while the pipe is produced. The data obtained by ultrasound sensors are digitized in a time window following a trigger pulse, and the digitized data are processed in a digital processor, for example a DSP, using wavelet transforms. The evaluated quantity is compared with a reference value, wherein a determined flaw-based signal can be uniquely associated with the flaw located on the pipe surface.Type: GrantFiled: July 28, 2006Date of Patent: August 24, 2010Assignee: V & M Deutschland GmbHInventors: Thomas Orth, Stefan Nitsche, Till Schmitte
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Patent number: 7783432Abstract: A method for nondestructive testing of the pipes for detecting surface flaws using magnetic leakage flux is disclosed. With of the method, flaws can be detected and analyzed in near-real-time while the pipe is produced. The data obtained with inductive coils, Hall sensors or GMR sensors are digitized, the digital data are buffered in a first memory, and a subset of the digital data are copied into a second memory. The copied data are transformed with a wavelet transformation and the resulting wavelet coefficients are filtered and/or modified. In an alternative embodiment, the digital data can be continuously supplied to a routine for wavelet transformation, which is performed using cascaded digital signal processing routines. The evaluated variable is compared with a reference value, wherein a determined flaw-based signal can be unambiguously associated with the position of the flaw.Type: GrantFiled: July 28, 2006Date of Patent: August 24, 2010Assignee: V & M Deutschland GmbHInventors: Thomas Orth, Stefan Nitsche, Till Schmitte
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Patent number: 7728586Abstract: The present invention pertains to a method for the nondestructive testing of pipes made of ferromagnetic steel by means of a stray flux, in which the pipe, which is moving in the longitudinal direction and alternatively additionally rotating, is magnetized by a constant field, and the generated magnetic flux is transmitted into the pipe in a contactless manner, and the flaws that are located in the near-surface area of the outer or inner surface of the pipe bring about magnetic stray fluxes, which emerge from the pipe surface and are detected by means of sensors. The amplitudes, preferably of the horizontal field component of the magnetic stray flux, which vary in the vertical direction, are detected, on the one hand, at a near-surface distance from the pipe outer surface, and, on the other hand, at a distance lying further remotely therefrom, and the detected signals are related to one another.Type: GrantFiled: June 10, 2005Date of Patent: June 1, 2010Assignee: V & M Deutschland GmbHInventors: Michael Kaack, Stefan Nitsche, Thomas Orth
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Publication number: 20080228412Abstract: A method for nondestructive testing of the pipes for detecting surface flaws using magnetic leakage flux is disclosed. With of the method, flaws can be detected and analyzed in near-real-time while the pipe is produced. The data obtained with inductive coils, Hall sensors or GMR sensors are digitized, the digital data are buffered in a first memory, and a subset of the digital data are copied into a second memory. The copied data are transformed with a wavelet transformation and the resulting wavelet coefficients are filtered and/or modified. In an alternative embodiment, the digital data can be continuously supplied to a routine for wavelet transformation, which is performed using cascaded digital signal processing routines. The evaluated variable is compared with a reference value, wherein a determined flaw-based signal can be unambiguously associated with the position of the flaw.Type: ApplicationFiled: July 28, 2006Publication date: September 18, 2008Applicant: V & M DEUTSCHLAND GMBHInventors: Thomas Orth, Stefan Nitsche, Till Schmitte
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Publication number: 20080210010Abstract: A method for nondestructive testing of the pipes for detecting surface flaws is disclosed. With of the method, flaws can be detected and analyzed in near-real-time while the pipe is produced. The data obtained by ultrasound sensors are digitized in a time window following a trigger pulse, and the digitized data are processed in a digital processor, for example a DSP, using wavelet transforms. The evaluated quantity is compared with a reference value, wherein a determined flaw-based signal can be uniquely associated with the flaw located on the pipe surface.Type: ApplicationFiled: July 28, 2006Publication date: September 4, 2008Inventors: Thomas Orth, Stefan Nitsche, Till Schmitte
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Publication number: 20080042645Abstract: The present invention pertains to a method for the nondestructive testing of pipes made of ferromagnetic steel by means of a stray flux, in which the pipe, which is moving in the longitudinal direction and alternatively additionally rotating, is magnetized by a constant field, and the generated magnetic flux is transmitted into the pipe in a contactless manner, and the flaws that are located in the near-surface area of the outer or inner surface of the pipe bring about magnetic stray fluxes, which emerge from the pipe surface and are detected by means of sensors. The amplitudes, preferably of the horizontal field component of the magnetic stray flux, which vary in the vertical direction, are detected, on the one hand, at a near-surface distance from the pipe outer surface, and, on the other hand, at a distance lying further remotely therefrom, and the detected signals are related to one another. Furthermore, the present invention pertains to a device for carrying out the method.Type: ApplicationFiled: June 10, 2005Publication date: February 21, 2008Applicant: V.& M. DEUSCHLAND GMBHInventors: Michael Kaack, Stefan Nitsche, Thomas Orth