Patents by Inventor Seetharamaiah Mannava
Seetharamaiah Mannava 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: 5735044Abstract: A crack weld repair and method, particularly, for a gas turbine engine blade or other metallic component in the engine, providing a metallic substrate, a metallic filler bonded onto a substrate bond surface on the metallic substrate, and a region having deep compressive residual stresses imparted by laser shock peening extending into the substrate beneath the substrate bond surface. One embodiment provides a laser shock peened surface below the weld material filled void in a damaged area of the component forming a region of deep compressive residual stresses imparted by laser shock peening (LSP) extending from the laser shock peened surface into the component. Optionally, the surface over the repaired area of the weld filled void may also be laser shock peened forming a second region of deep compressive residual stresses imparted by laser shock peening (LSP) extending from the laser shock peened surface into the weld repair.Type: GrantFiled: December 12, 1995Date of Patent: April 7, 1998Assignee: General Electric CompanyInventors: Stephen J. Ferrigno, William D. Cowie, Seetharamaiah Mannava
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Patent number: 5723078Abstract: A method of repairing a thermal barrier coating on an article designed for use in a hostile thermal environment, such as turbine, combustor and augmentor components of a gas turbine engine. The method is particularly suited for the repair of thermal barrier coatings composed of a metallic bond layer formed on the surface of the article, and a columnar ceramic layer overlaying the bond layer. The method entails the steps of cleaning the bond layer exposed by localized spallation, treating the bond layer so as to texture its exposed surface, and then depositing a ceramic material on the surface of the bond layer so as to form a ceramic repair layer that completely covers the bond layer. Deposition of the repair layer can be carried out such that its upper surface projects above the adjacent ceramic layer, followed by abrading the repair layer to a height substantially level with the ceramic layer.Type: GrantFiled: May 24, 1996Date of Patent: March 3, 1998Assignee: General Electric CompanyInventors: Bangalore A. Nagaraj, Seetharamaiah Mannava, Bhupendra K. Gupta
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Patent number: 5675892Abstract: A wide gap braze repair, particularly for a gas turbine engine vane or a component in the hot section of the engine. The repair is characterized by a braze filled void in a damaged area of the component, a laser shock peened surface over the repaired area of the braze filled void, and a region of deep compressive residual stresses imparted by laser shock peening (LSP) extending from the laser shock peened surface into the repair.Type: GrantFiled: June 20, 1996Date of Patent: October 14, 1997Assignee: General Electric CompanyInventors: Seetharamaiah Mannava, Stephen J. Ferrigno
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Patent number: 5674328Abstract: A method of laser shock peening a metallic part by firing a laser on a laser shock peening surface of the part which has been adhesively covered by tape having an ablative medium, preferably, a self adhering tape with an adhesive layer on one side of an ablative layer and a confinement medium without flowing a confinement curtain of fluid over the surface upon which the laser beam is firing. Continuous movement is provided between the part and the laser beam while continuously firing the laser beam, which repeatably pulses between relatively constant periods, on a laser shock peening surface of the part. Using a laser beam with sufficient power to vaporize the ablative medium so that the pulses form laser beam spots on the surface and a region having deep compressive residual stresses imparted by the laser shock peening process extending into the part from the surface.Type: GrantFiled: April 26, 1996Date of Patent: October 7, 1997Assignee: General Electric CompanyInventors: Seetharamaiah Mannava, Robert L. Yeaton, Albert E. McDaniel
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Patent number: 5674329Abstract: A method of laser shock peening a metallic part by firing a laser on a laser shock peening surface of the part which has been adhesively covered by tape having an ablative medium, preferably a self adhering tape with an adhesive layer on one side of an ablative layer, while flowing a curtain of water over the surface upon which the laser beam is firing. Continuous movement is provided between the part and the laser beam while continuously firing the laser beam, which repeatably pulses between relatively constant periods, on a laser shock peening surface of the part. Using a laser beam with sufficient power to vaporize the ablative medium so that the pulses form laser beam spots on the surface and a region having deep compressive residual stresses imparted by the laser shock peening process extending into the part from the surface.Type: GrantFiled: April 26, 1996Date of Patent: October 7, 1997Assignee: General Electric CompanyInventors: Seetharamaiah Mannava, Angel L. Ortiz, Jr., Robert L. Yeaton, Albert E. McDaniel, Jeffrey D. Losey
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Patent number: 5671628Abstract: A die having a metallic block with a depression, the depression having at least one cross-sectional transition zone, at least one laser shock peened surface encompassing at least a portion of the zone, a region having deep compressive residual stresses imparted by laser shock peening (LSP) extending into the airfoil from the laser shock peened surface. The die has been found to be useful for cold rolling blanks such when the metallic block is a cold rolling die block. The die may be adapted for forming a gas turbine engine component, such as a compressor blade, having an airfoil such that the depression corresponds to the airfoil.Type: GrantFiled: December 18, 1995Date of Patent: September 30, 1997Assignee: General Electric CompanyInventors: Herbert Halila, Seetharamaiah Mannava
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Patent number: 5620307Abstract: Gas turbine engine blade with a metallic airfoil having a radially outer tip extending chordwise between a leading edge and a trailing edge and at least one laser shock peened surface extending radially along at least a portion of the tip and a region having deep compressive residual stresses imparted by laser shock peening (LSP) extending into the airfoil from the laser shock peened surface.Type: GrantFiled: March 6, 1995Date of Patent: April 15, 1997Assignee: General Electric CompanyInventors: Seetharamaiah Mannava, Albert E. McDaniel, William D. Cowie, Herbert Halila, James E. Rhoda, Stephen J. Ferrigno
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Patent number: 5591009Abstract: Gas turbine engine fan blade with a metallic airfoil having a leading edge, a trailing edge, and a radially outer tip, and at least one laser shock peened surface located along the leading edge with a region having deep compressive residual stresses imparted by laser shock peening (LSP) extending into the airfoil from the laser shock peened surface.Type: GrantFiled: January 17, 1995Date of Patent: January 7, 1997Assignee: General Electric CompanyInventors: Seetharamaiah Mannava, Albert E. McDaniel, William D. Cowie, Herbert Halila, James E. Rhoda, James E. Gutknecht
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Patent number: 5584662Abstract: A wide gap braze repair, particularly for a gas turbine engine vane or a component in the hot section of the engine. The repair is characterized by a braze filled void in a damaged area of the component, a laser shock peened surface over the repaired area of the braze filled void, and a region of deep compressive residual stresses imparted by laser shock peening (LSP) extending from the laser shock peened surface into the repair.Type: GrantFiled: March 6, 1995Date of Patent: December 17, 1996Assignee: General Electric CompanyInventors: Seetharamaiah Mannava, Stephen J. Ferrigno
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Patent number: 5584586Abstract: A bearing element having a metallic body with a bearing contact curved surface portion, at least one laser shock peened surface encompassing at least a portion of the contact surface portion, and a region having deep compressive residual stresses imparted by laser shock peening (LSP) extending into the body from the laser shock peened surface. The present invention may be used for rolling elements such as ball bearing elements or elongated roller elements and for static elements such as races which may be singular or split and may have circumferentially spaced oil feed passages radially disposed therethrough.Type: GrantFiled: March 4, 1996Date of Patent: December 17, 1996Assignee: General Electric CompanyInventors: Dominick A. Casarcia, William D. Cowie, Seetharamaiah Mannava
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Patent number: 5569018Abstract: Gas turbine engine static component with a metallic panel section, either linear or curved, that is susceptible to cracks initiated by features on the component has an elongated laser shock peened region having deep compressive residual stresses imparted by laser shock peening (LSP) disposed between the feature and a portion of the panel section, which is to be protected from failure, such that the laser shock peened region diverts cracks that propagate from the feature away from the portion of the panel section. The laser shock peened region preferably extends through the component and is may be formed by simultaneously laser shock peening first and second laser shock peened surface areas to form the laser shock peened region.Type: GrantFiled: March 6, 1995Date of Patent: October 29, 1996Assignee: General Electric CompanyInventors: Seetharamaiah Mannava, William D. Cowie
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Patent number: 5525429Abstract: A metallic article and method for producing such an article, having a metallic substrate, at least one metallic layer sprayed onto a laser shock peened surface area of the substrate, and a region having deep compressive residual stresses imparted by laser shock peening extending into the substrate from the laser shock peened surface. The metallic substrate and or layer may be made from an alloy such as a Cobalt or a Nickel based superalloy. The substrate may be made from Nickel Base forgings or Titanium base forgings. An exemplary embodiment of the present invention is a gas turbine engine rotor component such a disk and, more particularly, a turbine disk suitable for use in a hot section of a gas turbine engine. The invention may be used for new or refurbished parts to restore dimensions of the component and, in particular, radial dimensions.Type: GrantFiled: March 6, 1995Date of Patent: June 11, 1996Assignee: General Electric CompanyInventors: Seetharamaiah Mannava, William D. Cowie, Stephen J. Ferrigno
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Patent number: 5522706Abstract: Turbomachinery rotor component, which may be a disk or drum rotor, having an annular rim disposed about a centerline for securing the blades to the rotor and that is subject to a tensile stress field due to centrifugal and thermal growth induced forces generated by the rotor when the rotor is rotating. An annular channel slot is cut around the rim, has outer annular overhanging rails, and has at least one stress riser in the form of a three sided slot cut in the radial direction through one of the rails. A region around rounded corners of the stress riser has deep compressive residual stresses imparted by laser shock peening and extends inward from a laser shocked surface of the component encompassed by the region.Type: GrantFiled: October 6, 1994Date of Patent: June 4, 1996Assignee: General Electric CompanyInventors: Seetharamaiah Mannava, William D. Cowie
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Patent number: 5492447Abstract: Turbomachinery rotor components having a metallic body with at least a portion of the body subject to a tensile stress field due to centrifugal and thermal growth induced forces generated by the rotor when the rotor is rotating, at least one stress riser in the stress field portion that causes stress concentration when the rotor is rotating, and at least one region of the component around the stress riser having deep compressive residual stresses imparted by laser shock peening (LSP).Type: GrantFiled: October 6, 1994Date of Patent: February 20, 1996Assignee: General Electric CompanyInventors: Seetharamaiah Mannava, Albert E. McDaniel, William D. Cowie
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Patent number: 5438441Abstract: Apparatus and method for performing material processing, such as drilling or welding, with a high intensity laser beam operating in the infrared spectrum, using a reflective holographic optical element (HOE) the surface of which is prepared to contain an image of the object under processing and energy intensity information, the object can be located in or out of line-of-sight with respect to the emitted laser beam.Type: GrantFiled: February 1, 1993Date of Patent: August 1, 1995Assignee: General Electric CompanyInventors: Todd J. Rockstroh, Seetharamaiah Mannava
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Patent number: 5368911Abstract: A method for manufacturing a composite material comprises the steps of furnishing a layer of a matrix material, forming a groove in the matrix-material layer using a laser to remove material from the layer of matrix material in the form of a groove, and placing a reinforcement into the groove. Preferably, the surface of the layer of matrix material is smoothed with a laser beam prior to formation of the groove. In most instances, more than one layer is desired, and the steps of furnishing, forming, and placing are repeated, using the same or different materials, to build up a multilayer composite material. Cylindrical, flat, or curved panel composite materials can be readily prepared, using metal, intermetallic, or ceramic materials for the matrix.Type: GrantFiled: March 27, 1992Date of Patent: November 29, 1994Assignee: General Electric CompanyInventors: Seetharamaiah Mannava, Vanon D. Pratt, Henry MacLaren, Joseph J. Jackson, Patrick M. Kenney
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Patent number: 5216808Abstract: A method for making or repairing a gas turbine engine component includes the step of directing a pulsed ultra-violet laser beam on a location of a film cooling hole after application of a thermal barrier coating to athermally remove any coating material which may be obstructing the cooling hole without damaging the engine component or removing any of the coating from the surface of the component around the cooling hole.Type: GrantFiled: December 13, 1991Date of Patent: June 8, 1993Assignee: General Electric CompanyInventors: James A. Martus, Paul P. Mehta, Seetharamaiah Mannava
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Patent number: 5187967Abstract: A hot forged article of a preselected profile is produced by heating a forging blank to elevated temperature and forging the blank at the elevated temperature between closed dies, to produce a forging of about the preselected profile of the final forging, but having flashing thereon. The flashing is removed by cooling the forging having flashing thereon to ambient temperature, and trimming the flashing from the forging by passing a trimming laser beam of sufficient power density to cut through the flashing along the preselected final profile of the forging. The forging may be post treated by passing a post treating excimer laser along the portion of the forging immediately adjacent the preselected profile, after the trimming laser has passed. The post treatment removes the heat affected zone, depending upon the energy level of the excimer laser.Type: GrantFiled: September 16, 1991Date of Patent: February 23, 1993Assignee: General Electric CompanyInventors: Jogender Singh, Sulekh C. Jain, Thomas W. Lloyd, Leroy A. Bates, Denis Lacroix, Ernest B. Cooper, Jr., Seetharamaiah Mannava, Serge B. Couture
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Patent number: 5012087Abstract: A system for detecting energy leakage from an optical fiber transmitting high power laser beams. A second optical fiber is placed together with the laser power transmitting fiber into a jacketing tube or conduit. The second fiber is connected at one end to a light source and at the other end to a photosensitive diode. Leakage of laser energy from the power transmitting fiber will cause a failure of the second optical fiber, reducing or terminating the transmission of light to the photosensitive diode. Energy leakage from the laser power transmitting fiber can therefore be detected by monitoring the output of the photosensitive diode.Type: GrantFiled: April 13, 1989Date of Patent: April 30, 1991Assignee: General Electric CompanyInventors: Todd J. Rockstroh, SeethaRamaiah Mannava