Patents by Inventor Trikur A. Ramanarayanan

Trikur A. Ramanarayanan 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).

  • Patent number: 8470097
    Abstract: A method of providing sulfidation corrosion resistance and corrosion induced fouling resistance to a heat transfer component surface includes providing a silicon containing steel composition including an alloy and a Si-partitioned non-metallic film formed on a surface of the alloy. The alloy is formed from the composition ?, ?,and ?, in which ? is a metal selected from the group consisting of Fe, Ni, Co, and mixtures thereof, ? is Si, and ? is at least one alloying element selected from the group consisting of Cr, Al, Mn, Ti, Zr, Hf, V, Nb, Ta, Mo, W, Sc, La, Y, Ce, Ru, Rh, Ir, Pd, Pt, Cu, Ag, Au, Ga, Ge, As, In, Sn, Sb, Pb, B, C, N, P, O, S and mixtures thereof. The Si-partitioned non-metallic film comprises at least one of sulfide, oxysulfide and mixtures thereof.
    Type: Grant
    Filed: May 15, 2012
    Date of Patent: June 25, 2013
    Assignee: ExxonMobil Research and Engineering Company
    Inventors: ChangMin Chun, Mark A Greaney, Thomas Bruno, Ian A Cody, Trikur A Ramanarayanan, LeRoy A Clavenna
  • Patent number: 8465599
    Abstract: A method of providing sulfidation corrosion resistance and corrosion induced fouling resistance for a heat transfer component is disclosed. The heat transfer component includes a heat exchange surface formed from a chromium-enriched oxide containing material formed from the composition ?, ?, and ?, wherein ? is a steel containing at least about 5 to about 40 wt. % chromium, ? is a chromium enriched oxide (M3O4 or M2O3 or mixtures thereof) formed on the surface of the steel ?, wherein M is a metal containing at least 5 wt. % Cr based on the total weight of the metal M, and ? is a top layer formed on the surface of the chromium-enriched oxide ?, comprising sulfide, oxide, oxysulfide, and mixtures thereof. The top layer ? comprises iron sulfide (Fe1-xS), iron oxide (Fe3O4), iron oxysulfide, iron-chromium sulfide, iron-chromium oxide, iron-chromium oxysulfide, and mixtures thereof.
    Type: Grant
    Filed: July 28, 2011
    Date of Patent: June 18, 2013
    Assignee: ExxonMobil Research and Engineering Company
    Inventors: ChangMin Chun, Mark A. Greaney, Thomas Bruno, Ian A. Cody, Trikur A. Ramanarayanan
  • Publication number: 20120273091
    Abstract: A method of providing sulfidation corrosion resistance and corrosion induced fouling resistance to a heat transfer component surface includes providing a silicon containing steel composition including an alloy and a Si-partitioned non-metallic film formed on a surface of the alloy. The alloy is formed from the composition ?, ?, and t, in which ? is a metal selected from the group consisting of Fe, Ni, Co, and mixtures thereof, ? is Si, and t is at least one alloying element selected from the group consisting of Cr, Al, Mn, Ti, Zr, Hf, V, Nb, Ta, Mo, W, Sc, La, Y, Ce, Ru, Rh, Ir, Pd, Pt, Cu, Ag, Au, Ga, Ge, As, In, Sn, Sb, Pb, B, C, N, P, O, S and mixtures thereof. The Si-partitioned non-metallic film comprises at least one of sulfide, oxysulfide and mixtures thereof.
    Type: Application
    Filed: May 15, 2012
    Publication date: November 1, 2012
    Applicant: EXXONMOBIL RESEARCH AND ENGINEERING COMPANY
    Inventors: ChangMin Chun, Mark A. Greaney, Thomas Bruno, Ian A. Cody, Trikur A. Ramanarayanan, LeRoy R. Clavenna
  • Patent number: 8211548
    Abstract: A heat transfer component that is resistant to both corrosion and fouling is disclosed having a heat exchange surface formed from a silicon containing steel composition including an alloy and a non-metallic film formed on a surface of the alloy. The alloy is formed from the composition ?, ?, and ?, in which ? is a metal selected from the group consisting of Fe, Ni, Co, and mixtures thereof, ? is Si, and ? is at least one alloying element selected from the group consisting of Cr, Al, Mn, Ti, Zr, Hf, V, Nb, Ta, Mo, W, Sc, La, Y, Ce, Ru, Rh, Ir, Pd, Pt, Cu, Ag, Au, Ga, Ge, As, In, Sn, Sb, Pb, B, C, N, P, O, S and mixtures thereof. The non-metallic film comprises sulfide, oxide, carbide, nitride, oxysulfide, oxycarbide, oxynitride and mixtures thereof. The surface roughness of the heat transfer component is less than 40 micro inches.
    Type: Grant
    Filed: December 20, 2006
    Date of Patent: July 3, 2012
    Assignee: ExxonMobil Research & Engineering Co.
    Inventors: ChangMin Chun, Mark A. Greaney, Thomas Bruno, Ian A. Cody, Trikur A. Ramanarayanan, LeRoy R. Clavenna
  • Publication number: 20110277888
    Abstract: A method of providing sulfidation corrosion resistance and corrosion induced fouling resistance for a heat transfer component is disclosed. The heat transfer component includes a heat exchange surface formed from a chromium-enriched oxide containing material formed from the composition ?, ?, and ?, wherein ? is a steel containing at least about 5 to about 40 wt. % chromium, ? is a chromium enriched oxide (M3O4 or M2O3 or mixtures thereof) formed on the surface of the steel ?, wherein M is a metal containing at least 5 wt. % Cr based on the total weight of the metal M, and ? is a top layer formed on the surface of the chromium-enriched oxide ?, comprising sulfide, oxide, oxysulfide, and mixtures thereof. The top layer ? comprises iron sulfide (Fe1-xS), iron oxide (Fe3O4), iron oxysulfide, iron-chromium sulfide, iron-chromium oxide, iron-chromium oxysulfide, and mixtures thereof.
    Type: Application
    Filed: July 28, 2011
    Publication date: November 17, 2011
    Applicant: EXXONMOBIL RESEARCH AND ENGINEERING COMPANY
    Inventors: ChangMin CHUN, Mark A. GREANEY, Thomas BRUNO, Ian A. CODY, Trikur A. RAMANARAYANAN
  • Patent number: 8037928
    Abstract: A heat transfer component that is resistant to corrosion and fouling is disclosed. The heat transfer component includes a heat exchange surface formed from a chromium-enriched oxide containing material formed from the composition ?, ?, and ?, wherein ? is a steel containing at least about 5 to about 40 wt. % chromium, ? is a chromium enriched oxide (M3O4 or M2O3 or mixtures thereof) formed on the surface of the steel ?, wherein M is a metal containing at least 5 wt. % Cr based on the total weight of the metal M, and ? is a top layer formed on the surface of the chromium-enriched oxide ?, comprising sulfide, oxide, oxysulfide, and mixtures thereof. The top layer ? comprises iron sulfide (Fe1-xS), iron oxide (Fe3O4), iron oxysulfide, iron-chromium sulfide, iron-chromium oxide, iron-chromium oxysulfide, and mixtures thereof. The metal M of the chromium enriched oxide (M3O4 or M2O3 or mixtures thereof) may comprise Fe, Cr, and constituting elements of the steel ?.
    Type: Grant
    Filed: December 20, 2006
    Date of Patent: October 18, 2011
    Assignee: ExxonMobil Research & Engineering Company
    Inventors: ChangMin Chun, Mark A. Greaney, Thomas Bruno, Ian A. Cody, Trikur A. Ramanarayanan
  • Patent number: 8029914
    Abstract: High performance coated metal compositions resistant to metal dusting corrosion and methods of providing such compositions are provided by the present invention. The coated metal compositions are represented by the structure (PQR), wherein P is an oxide layer at the surface of (PQR), Q is a coating metal layer interposed between P and R, and R is a base metal. P includes alumina, chromia, silica, mullite or mixtures thereof. Q includes Ni and Al, and at least one element selected from the group consisting of Cr, Si, Mn, Fe, Co, B, C, N, P, Ga, Ge, As, In, Sn, Sb, Pb, Sc, La, Y, Ce, Ti, Zr, Hf, V, Nb, Ta, Mo, W, Ru, Rh, Ir, Pd, Pt, Cu, Ag, Au and mixtures thereof. R is selected from the group consisting of carbon steels, low chromium steels, ferritic stainless steels, austenetic stainless steels, duplex stainless steels, Inconel alloys, Incoloy alloys, Fe—Ni based alloys, Ni-based alloys and Co-based alloys.
    Type: Grant
    Filed: July 10, 2007
    Date of Patent: October 4, 2011
    Assignee: ExxonMobile Research and Engineering Company
    Inventors: Kenneth E. Bagnoli, G. Phillip Anderson, Trikur A. Ramanarayanan, ChangMin Chun
  • Patent number: 7422804
    Abstract: A metal dusting resistant composition comprises an alloy capable of forming a thermally stable titanium carbide coating on its surface when exposed to a carbon supersaturated environment and, a protective coating on the alloy surface comprising an outer oxide layer and an inner carbide layer between the alloy surface and the outer layer.
    Type: Grant
    Filed: February 1, 2005
    Date of Patent: September 9, 2008
    Assignee: ExxonMobil Research and Engineering Company
    Inventors: ChangMin Chun, James D. Mumford, Trikur A. Ramanarayanan
  • Publication number: 20080199349
    Abstract: Alloy compositions which are resistant to metal dusting corrosion are provided by the present invention. Also provided are methods for preventing metal dusting on metal surfaces exposed to carbon supersaturated environments. The alloy compositions include an alloy (PQR), and a multi-layer oxide film on the surface of the alloy (PQR). The alloy (PQR) includes a metal (P) selected from the group consisting of Fe, Ni, Co, and mixtures thereof, an alloying metal (Q) comprising Cr, Mn, and either Al, Si, or Al/Si, and an alloying element (R). When the alloying metal (Q) includes Al, the multi-layer oxide film on the surface of the alloy includes at least three oxide layers. When the alloying metal (Q) includes Si, the multi-layer oxide film on the surface of the alloy (PQR) includes at least four oxide layers. When the alloying metal (Q) includes Al and Si, the multi-layer oxide film on the surface of the alloy (PQR) includes at least three oxide layers.
    Type: Application
    Filed: February 8, 2008
    Publication date: August 21, 2008
    Inventors: ChangMin Chun, Trikur A. Ramanarayanan
  • Patent number: 7354660
    Abstract: Alloy compositions which are resistant to metal dusting corrosion are provided by the present invention. Also provided are methods for preventing metal dusting on metal surfaces exposed to carbon supersaturated environments. The alloy compositions include an alloy (PQR), and a multi-layer oxide film on the surface of the alloy (PQR). The alloy (PQR) includes a metal (P) selected from the group consisting of Fe, Ni, Co, and mixtures thereof, an alloying metal (Q) comprising Cr, Mn, and either Al, Si, or Al/Si, and an alloying element (R). When the alloying metal (Q) includes Al, the multi-layer oxide film on the surface of the alloy includes at least three oxide layers. When the alloying metal (Q) includes Si, the multi-layer oxide film on the surface of the alloy (PQR) includes at least four oxide layers. When the alloying metal (Q) includes Al and Si, the multi-layer oxide film on the surface of the alloy (PQR) includes at least three oxide layers.
    Type: Grant
    Filed: May 10, 2005
    Date of Patent: April 8, 2008
    Assignee: ExxonMobil Research and Engineering Company
    Inventors: ChangMin Chun, Trikur A. Ramanarayanan
  • Publication number: 20080020216
    Abstract: High performance coated metal compositions resistant to metal dusting corrosion and methods of providing such compositions are provided by the present invention. The coated metal compositions are represented by the structure (PQR), wherein P is an oxide layer at the surface of (PQR), Q is a coating metal layer interposed between P and R, and R is a base metal. P includes alumina, chromia, silica, mullite or mixtures thereof. Q includes Ni and Al, and at least one element selected from the group consisting of Cr, Si, Mn, Fe, Co, B, C, N, P, Ga, Ge, As, In, Sn, Sb, Pb, Sc, La, Y, Ce, Ti, Zr, Hf, V, Nb, Ta, Mo, W, Ru, Rh, Ir, Pd, Pt, Cu, Ag, Au and mixtures thereof. R is selected from the group consisting of carbon steels, low chromium steels, ferritic stainless steels, austenetic stainless steels, duplex stainless steels, Inconel alloys, Incoloy alloys, Fe—Ni based alloys, Ni-based alloys and Co-based alloys.
    Type: Application
    Filed: July 10, 2007
    Publication date: January 24, 2008
    Inventors: Kenneth Bagnoli, G. Anderson, Trikur Ramanarayanan, ChangMin Chun
  • Publication number: 20070207329
    Abstract: A heat transfer component that is resistant to corrosion and fouling is disclosed. The heat transfer component includes a heat exchange surface formed from a chromium-enriched oxide containing material formed from the composition ?, ?, and ?, wherein ? is a steel containing at least about 5 to about 40 wt. % chromium, ? is a chromium enriched oxide (M3O4 or M2O3 or mixtures thereof) formed on the surface of the steel ?, wherein M is a metal containing at least 5 wt. % Cr based on the total weight of the metal M, and ? is a top layer formed on the surface of the chromium-enriched oxide ?, comprising sulfide, oxide, oxysulfide, and mixtures thereof. The top layer ? comprises iron sulfide (Fe1-xS), iron oxide (Fe3O4), iron oxysulfide, iron-chromium sulfide, iron-chromium oxide, iron-chromium oxysulfide, and mixtures thereof. The metal M of the chromium enriched oxide (M3O4 or M2O3 or mixtures thereof) may comprise Fe, Cr, and constituting elements of the steel ?.
    Type: Application
    Filed: December 20, 2006
    Publication date: September 6, 2007
    Inventors: ChangMin Chun, Mark Greaney, Thomas Bruno, Ian Cody, Trikur Ramanarayanan
  • Publication number: 20070178322
    Abstract: A heat transfer component that is resistant to both corrosion and fouling is disclosed having a heat exchange surface formed from a silicon containing steel composition including an alloy and a non-metallic film formed on a surface of the alloy. The alloy is formed from the composition ?, ?, and ?, in which ? is a metal selected from the group consisting of Fe, Ni, Co, and mixtures thereof, ? is Si, and ? is at least one alloying element selected from the group consisting of Cr, Al, Mn, Ti, Zr, Hf, V, Nb, Ta, Mo, W, Sc, La, Y, Ce, Ru, Rh, Ir, Pd, Pt, Cu, Ag, Au, Ga, Ge, As, In, Sn, Sb, Pb, B, C, N, P, 0, S and mixtures thereof. The non-metallic film comprises sulfide, oxide, carbide, nitride, oxysulfide, oxycarbide, oxynitride and mixtures thereof. The surface roughness of the heat transfer component is less than 40 micro inches.
    Type: Application
    Filed: December 20, 2006
    Publication date: August 2, 2007
    Applicant: ExxonMobil Research and Engineering Company
    Inventors: ChangMin Chun, Mark Greaney, Thomas Bruno, Ian Cody, Trikur Ramanarayanan, LeRoy Clavenna
  • Publication number: 20060257675
    Abstract: Alloy compositions which are resistant to metal dusting corrosion are provided by the present invention. Also provided are methods for preventing metal dusting on metal surfaces exposed to carbon supersaturated environments. The alloy compositions include an alloy (PQR), and a multi-layer oxide film on the surface of the alloy (PQR). The alloy (PQR) includes a metal (P) selected from the group consisting of Fe, Ni, Co, and mixtures thereof, an alloying metal (Q) comprising Cr, Mn, and either Al, Si, or Al/Si, and an alloying element (R). When the alloying metal (Q) includes Al, the multi-layer oxide film on the surface of the alloy includes at least three oxide layers. When the alloying metal (Q) includes Si, the multi-layer oxide film on the surface of the alloy (PQR) includes at least four oxide layers. When the alloying metal (Q) includes Al and Si, the multi-layer oxide film on the surface of the alloy (PQR) includes at least three oxide layers.
    Type: Application
    Filed: May 10, 2005
    Publication date: November 16, 2006
    Inventors: ChangMin Chun, Trikur Ramanarayanan
  • Publication number: 20050170197
    Abstract: A metal dusting resistant composition comprises an alloy capable of forming a thermally stable titanium carbide coating on its surface when exposed to a carbon supersaturated environment and, a protective coating on the alloy surface comprising an outer oxide layer and an inner carbide layer between the alloy surface and the outer layer.
    Type: Application
    Filed: February 1, 2005
    Publication date: August 4, 2005
    Inventors: ChangMin Chun, James Mumford, Trikur Ramanarayanan
  • Patent number: 5869195
    Abstract: Corrosion of conventional refinery steels due to sulfur bearing, carboxylic acid containing hydrocarbon materials is minimized by forming on the surface of the steel a fine grain iron sulfide film where at least the steel surface is substantially all of a pearlite microstructure.
    Type: Grant
    Filed: January 3, 1997
    Date of Patent: February 9, 1999
    Assignee: Exxon Research and Engineering Company
    Inventors: Trikur A. Ramanarayanan, Adnan Ozekcin
  • Patent number: 5520751
    Abstract: The present invention is a process for forming protective films on an alloy substrate by: oxidizing an alloy comprising iron and chromium in an oxygen containing atmosphere, said alloy containing from about 5 to about 15 wt % chromium, at a temperature of from about 200.degree. C. (473.degree. K.) to about 1400.degree. C. (1673.degree. K.), more preferably 300.degree. C. (573.degree. K.) to 600.degree. C. (873.degree. K.) wherein the partial pressure of oxygen in said oxygen containing atmosphere is above or equal to the dissociation pressure of Fe.sub.3 O.sub.4 and FeO below or equal to the dissociation pressure of Fe.sub.2 O.sub.3 within the specified temperature range, and for a time sufficient to effect the formation of a film comprising iron-chromium oxide (FeCr.sub.2 O.sub.4) spinel on the surface of said alloy. In a further embodiment, the film may additionally contain Silicon.
    Type: Grant
    Filed: August 23, 1994
    Date of Patent: May 28, 1996
    Assignee: Exxon Research and Engineering Company
    Inventors: Vinod K. Pareek, Trikur A. Ramanarayanan, James D. Mumford, Adnan Ozekcin
  • Patent number: 5464523
    Abstract: A method and a sensor to measure the sulfur activity in sulfur-containing environments are disclosed. The active component is a non-stoichiometric metal sulfide foil or film. In the case of a thin sulfide film, a ceramic substrate is employed for improved mechanical rigidity. The electrical conductivity of the sulfide is related to the sulfur activity of the process stream to which it is exposed.
    Type: Grant
    Filed: May 18, 1994
    Date of Patent: November 7, 1995
    Assignee: Exxon Research & Engineering Co.
    Inventors: Trikur A. Ramanarayanan, Vinod K. Pareek, James D. Mumford, III, Horst Witzke
  • Patent number: 5279651
    Abstract: An organic salt, 2,4 Diamino-6-mercapto pyrimidine sulfate, has been combined with oxysalts of group VB or IVB of the periodic table to provide inorganic/organic inhibitor formulations having excellent corrosion resistant characteristics.
    Type: Grant
    Filed: December 18, 1992
    Date of Patent: January 18, 1994
    Assignee: Exxon Research & Engineering Company
    Inventors: Trikur A. Ramanarayanan, Hyacinth L. Vedage
  • Patent number: 5158693
    Abstract: Quartenized derivatives of oligoquinoline have been reacted with refractory metal oxysalts to generate oligoquinolinium metal oxide salts which provide excellent corrosion inhibition of iron based alloy articles in sulfur containing media.
    Type: Grant
    Filed: August 29, 1991
    Date of Patent: October 27, 1992
    Assignee: Exxon Research and Engineering Co.
    Inventors: Trikur A. Ramanarayanan, Long Y. Chiang