Patents by Inventor Dirk Letzel

Dirk Letzel 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).

  • Publication number: 20230330743
    Abstract: The invention relates to a method and to a spraying apparatus (10) for the thermal surface treatment of a metal product (1). The metal product (1) is conveyed in a transport direction (T) through a treatment section (12) of a spraying apparatus (10) equipped with cooling nozzles (16) while cooling fluid is discharged through the cooling nozzles (16) of the spraying apparatus (10) onto the surfaces of the metal product (1), wherein the metal product (1) has—viewed in the transport direction (T) of the metal product (1)—a front section (4) and a trailing rear section (5). The cooling of the surfaces of the metal product (1) within the spraying apparatus (10) occurs in such a manner that the rear section (5) of the metal product (1) is cooled more significantly than its front section (4).
    Type: Application
    Filed: August 31, 2021
    Publication date: October 19, 2023
    Applicant: SMS group GmbH
    Inventors: Dirk Letzel, Uwe Plociennik, Volker Mers, Axel Stavenow, Ina Hüllen, Harminder Singh, Ingo OlgeMöller
  • Patent number: 7849911
    Abstract: A device for continuous casting and direct deformation of a metal strand, with a strand guide which is curved after the continuous casting mold in the direction of strand travel, a spray device for liquid coolant, a bending-straightening unit, and an automatic control system for a uniform temperature field in the strand cross section. The cast strand is cooled with a liquid coolant only in the longitudinal sections in which the cast strand is liquid in the cross section. The curved strand guide with the spray device for liquid coolant is followed by a dry zone, which operates without liquid coolant and serves as insulation against the elimination of radiant heat and systematically surrounds the cast strand. A reduction line is provided, which includes individual, hydraulically adjustable deforming rolls or several hydraulically adjustable roll segments and precedes, coincides with, or follows the region of the bending-straightening unit.
    Type: Grant
    Filed: September 7, 2006
    Date of Patent: December 14, 2010
    Assignee: SMS Siemag Aktiengesellschaft
    Inventors: Axel Weyer, Dirk Letzel, Horst Gärtner, Wilfried Milewski, Adolf Gustav Zajber
  • Patent number: 7284593
    Abstract: The invention relates to a method for collecting and evacuating run-off water from the inner arc of the strand guide (8) of a beam blank casting machine, according to which the cast strand (2) is solidified and the required dissipation of heat is achieved, among other things, by sprayed water, whereby run-off water can also collect on the inner arc of the strand (2). The run-off water is collected using a suction head (1). The run-off water that is collected in the suction head is fluidized using fluidizers or momentum inhibitors. The fluidized water is sucked off and the water-air mixture is split into water and air in a separation device. The invention also relates to a device for carrying out said method, comprising at least one suction device that is arranged or can be driven along the strand guide (8), said suction device having an attachable suction head (1) and being equipped with fluidizers. The suction device (4) is driven along the beam blank preliminary section (9) by means of manipulators (7).
    Type: Grant
    Filed: March 11, 2003
    Date of Patent: October 23, 2007
    Assignee: SMS Demag AG
    Inventors: Dirk Letzel, Josef Kockentiedt, Thomas Fest, Jürgen Friedrich, Adolf-Gustav Zajber
  • Publication number: 20070023161
    Abstract: A method for the continuous casting and direct deformation of a metal strand, especially a cast steel strand, includes guiding the metal strand in a curved strand glide after the continuous casting mold, subjecting the strand to a secondary cooling with a liquid coolant, and preparing the strand in an automatically controlled way for the deformation pass at a uniform temperature field in the strand cross-section, such that the cast strand is cooled with a liquid coolant only in the longitudinal sections in which the cast strand is liquid in the cross-section. The temperature of the cast strand is equalized in a transition zone before, in, and/or after a bending-straightening unit by insulation of the exterior surface that is radiating heat, without the use of the liquid coolant, and is further equalized by heat radiation in zones until the temperature field consists of elliptical, horizontally oriented isotherms.
    Type: Application
    Filed: September 7, 2006
    Publication date: February 1, 2007
    Inventors: Axel Weyer, Dirk Letzel, Horst Gartner, Wilfried Milewski, Adolf Zajber
  • Patent number: 7159642
    Abstract: A method and strand guide for supporting, guiding and cooling casting strands (1) made of steel, especially preliminary sections (2) for girders, which are cooled by injected water (29) and are drawn, serve to prevent cracks, especially surface cracks, from appearing in the microstructure by adapting the cooling conditions of the surface of the strand in the region of the secondary cooling, and serve to prevent undercooling of the strand shell, wherein in order to avoid an undesirable solidification structure on the upper flange edges or in other cross-sectional areas, the cooling and support of the beam blank format are so adapted to the solidification range that cooling and support are provided exclusively where a crater is formed.
    Type: Grant
    Filed: August 7, 2001
    Date of Patent: January 9, 2007
    Assignee: SMS Demag
    Inventors: Adolf Gustav Zajber, Dirk Letzel, Wilfried Milewski, Thomas Fest, Heinz-Dietrich Schneider, Lothar Fischer, Herbert Brotzki
  • Patent number: 7137437
    Abstract: Continuously cast products (12) are often provided with surface defects such as oscillation marks (17) and other non-homogeneous structures in the cast state thereof during production in a casting die (11) of a continuous casting plant (10). Defects which render a strip useless for superior applications also frequently occur on the strip surface during subsequent milling of the slab (12?) into a strip. The aim of the invention is to minimize said defects and provide the rolling mill with a slab (12?) having a desired preliminary profile and an improved near-surface structure. Said aim is achieved by arranging a reducing roll stand (30) in the area of the bending rolls or straightening driver rolls (24) within the continuous casting plant (10).
    Type: Grant
    Filed: January 16, 2004
    Date of Patent: November 21, 2006
    Assignee: SMS Demag AG
    Inventors: Adolf Gustav Zajber, Dirk Letzel
  • Patent number: 7121323
    Abstract: The invention relates to a method and a continuous casting device for the direct shaping of a metal strand, in particular a steel cast strand (1) of any format (1d). According to said method, the cast strand (1) is only cooled by a liquid coolant (4) in longitudinal sections (6), where the interior of the cast strand (1) remains liquefied and the temperature of the cast strand (1) in a transition zone (7) upstream of, in and/or downstream of a bending and straightening unit (8) is evened out by an insulation of the exterior surface (1b), essentially without the use of a liquid coolant (4), and by progressive thermal radiation. The cast strand (1) is shaped in a dynamically variable reduction section (9) as a result of the compressive strength that is measured on individual shaping rolls (10) or roll segments (11), depending on the compressive force that can be locally applied.
    Type: Grant
    Filed: January 30, 2003
    Date of Patent: October 17, 2006
    Assignee: SMS Demag AG
    Inventors: Axel Weyer, Dirk Letzel, Horst Gärtner, Wilfried Milewski, Adolf Gustav Zajber
  • Publication number: 20060191661
    Abstract: The invention relates to a continuous casting mold for casting molten metals, particularly steel materials, at high casting rates to form polygonal billet, bloom, and preliminary section castings (1) and the like. Said mold is comprised of a tubular mold (2) made of copper or of copper alloys whose entry cross-section (3) on the pouring-in side (4) has both a cross-section (5), which is enlarged compared to the exit cross-section (6) on the casting exit side (7), and corner radii (8). The continuous casting mold can be improved in a technologically process-oriented manner with regard to requirements concerning the cooling processes. To this end, the inner geometric cross-sectional shape (9) and the associated dimensions (10) are provided so that they are analogous to the amount of solidification heat, which is capable of being locally dissipated, at a chosen casting rate and are analogous to the extension of the tubular mold (2).
    Type: Application
    Filed: October 1, 2003
    Publication date: August 31, 2006
    Inventors: Adolf Zajber, Dirk Letzel, Josef Kockentiedt, Uwe Plociennik
  • Publication number: 20060054297
    Abstract: Continuously cast products (12) are often provided with surface defects such as oscillation marks (17) and other non-homogeneous structures in the cast state thereof during production in a casting die (11) of a continuous casting plant (10). Defects which render a strip useless for superior applications also frequently occur on the strip surface during subsequent milling of the slab (12?) into a strip. The aim of the invention is to minimize said defects and provide the rolling mill with a slab (12?) having a desired preliminary profile and an improved near-surface structure. Said aim is achieved by arranging a reducing roll stand (30) in the area of the bending rolls or straightening driver rolls (24) within the continuous casting plant (10).
    Type: Application
    Filed: January 16, 2004
    Publication date: March 16, 2006
    Inventors: Adolf Zajber, Dirk Letzel
  • Publication number: 20050211413
    Abstract: The invention relates to a method for collecting and evacuating run-off water from the inner arc of the strand guide (8) of a beam blank casting machine, according to which the cast strand (2) is solidified and the required dissipation of heat is achieved, among other things, by sprayed water, whereby run-off water can also collect on the inner arc of the strand (2). The run-off water is collected using a suction head (1). The run-off water that is collected in the suction head is fluidised using fluidisers or momentum inhibitors. The fluidised water is sucked off and the water-air mixture is split into water and air in a separation device. The invention also relates to a device for carrying out said method, comprising at least one suction device that is arranged or can be driven along the strand guide (8), said suction device having an attachable suction head (1) and being equipped with fluidisers. The suction device (4) is driven along the beam blank preliminary section (9) by means of manipulators (7).
    Type: Application
    Filed: March 11, 2003
    Publication date: September 29, 2005
    Inventors: Dirk Letzel, Josef Kockntiedt, Thomas Fest, Jurgen Friedrich, Adolf-Gustav Zajber
  • Publication number: 20050011629
    Abstract: The invention relates to a method and a continuous casting device for the direct shaping of a metal strand, in particular a steel cast stand (1) of any format (1d). According to said method, the cast strand (1) is only cooled by a liquid coolant (4) in longitudinal sections (6), where the interior of the cast strand (1) remains liquefied and the temperature of the cast strand (1) in a transition zone (7) upstream of, in and/or downstream of a bending and straightening unit (8) is evened out by an insulation of the exterior surface (1b), essentially without the use of a liquid coolant (4), and by progressive thermal radiation. The cast strand (1) is shaped in a dynamically variable reduction section (9) as a result of the compressive strength that is measured on individual shaping rolls (10) or roll segments (11), depending on the compressive force that can be locally applied.
    Type: Application
    Filed: January 30, 2003
    Publication date: January 20, 2005
    Inventors: Axel Weyer, Dirk Letzel, Horst Gartner, Wilfried Milewski, Adolf Zajber
  • Publication number: 20040255987
    Abstract: The invention relates to a method and a device for draining waste water (7) from the inner bend of the strand guide (3) of a beam blank casting machine. In order to drain said waste water from the beam blank in a targeted and controlled manner, a draining device (6) is arranged in the area of the strand guide (4) for the beam blank, said device being provided with jet nozzles (8). Under the effect of jets (13, 14) directed with high energy against the water flow direction, the waste water is lifted on the formation of a banking-up pressure by means of said draining device (6), directed at the lateral edges (11) of the inner bend (4) of the beam blank (10) and collected in a sintered groove (9), arranged thereunder.
    Type: Application
    Filed: April 5, 2004
    Publication date: December 23, 2004
    Inventors: Heinz-Dietrich Schneider, Jurgen friedrich, Herbert Brotzki, Dirk Letzel
  • Patent number: 6712123
    Abstract: In a method for changing the section of a billet of a continuous casting plant during continuous casting, wherein opposed sides of the billet are in contact with oppositely positioned roll supports arranged below a continuous casting die, wherein the roll supports are comprised of segments having rolls, wherein adjoining ones of the segments of each roll support are connected to one another by a jointed connection and wherein each segment is configured to be adjustable independent of the other segments with respect to an angular position relative to the billet, and wherein in an initial position the segments of the roll supports are adjusted to a uniform billet section, a thickness reduction can be achieved by advancing sequentially in a direction of continuous casting the segments toward the billet by moving the jointed connections toward the billet in a controlled sequence of adjusting steps or a thickness increase can be achieved by moving sequentially in a direction of continuous casting the segments away
    Type: Grant
    Filed: July 13, 2000
    Date of Patent: March 30, 2004
    Assignee: SMS Schloemann-Siemag Aktiengesellschaft
    Inventors: Axel Weyer, Dirk Letzel, Reiner Külchen, Adolf Zajber
  • Publication number: 20040020632
    Abstract: A method and strand guide for supporting, guiding and cooling casting strands (1) made of steel, especially preliminary sections (2) for girders, which are cooled by injected water (29) and are drawn, serve to prevent cracks, especially surface cracks, from appearing in the microstructure by adapting the cooling conditions of the surface of the strand in the region of the secondary cooling, and serve to prevent undercooling of the strand shell, wherein in order to avoid an undesirable solidification structure on the upper flange edges or in other cross-sectional areas, the cooling and support of the beam blank format are so adapted to the solidification range that cooling and support are provided exclusively where a crater is formed.
    Type: Application
    Filed: July 28, 2003
    Publication date: February 5, 2004
    Inventors: Adolf Gustav Zajber, Dirk Letzel, Wilfried Milewski, Thomas Fest, Heinz-Dietrich Schneider, Lothar Fischer, Herbert Brotzki