Patents by Inventor Raghavan Ayer

Raghavan Ayer 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: 11155905
    Abstract: Improved steel compositions and methods of making the same are provided. The present disclosure provides advantageous wear resistant steel. More particularly, the present disclosure provides high manganese (Mn) steel having enhanced wear resistance, and methods for fabricating high manganese steel compositions having enhanced wear resistance. The advantageous steel compositions/components of the present disclosure improve one or more of the following properties: wear resistance, ductility, crack resistance, erosion resistance, fatigue life, surface hardness, stress corrosion resistance, fatigue resistance, and/or environmental cracking resistance. In general, the present disclosure provides high manganese steels tailored to resist wear and/or erosion.
    Type: Grant
    Filed: May 11, 2018
    Date of Patent: October 26, 2021
    Assignees: ExxonMobil Research and Engineering Company, POSCO
    Inventors: Hyunwoo Jin, Ning Ma, Raghavan Ayer, Russell Robert Mueller, Hak-Cheol Lee, Jong-Kyo Choi, In-Shik Suh
  • Publication number: 20180258515
    Abstract: Improved steel compositions and methods of making the same are provided. The present disclosure provides advantageous wear resistant steel. More particularly, the present disclosure provides high manganese (Mn) steel having enhanced wear resistance, and methods for fabricating high manganese steel compositions having enhanced wear resistance. The advantageous steel compositions/components of the present disclosure improve one or more of the following properties: wear resistance, ductility, crack resistance, erosion resistance, fatigue life, surface hardness, stress corrosion resistance, fatigue resistance, and/or environmental cracking resistance. In general, the present disclosure provides high manganese steels tailored to resist wear and/or erosion.
    Type: Application
    Filed: May 11, 2018
    Publication date: September 13, 2018
    Inventors: Hyunwoo Jin, Ning Ma, Raghavan Ayer, Russell Robert Mueller, Hak-Cheol Lee, Jong-Kyo Choi, In-Shik Suh
  • Publication number: 20180169799
    Abstract: Weld metals and methods for welding ferritic steels are provided. The weld metals have high strength and high ductile tearing resistance and are suitable for use in strain based pipelines. The weld metals are comprised of between 0.03 and 0.08 wt % carbon, between 2.0 and 3.5 wt % nickel, not greater than about 2.0 wt % manganese, not greater than about 0.80 wt % molybdenum, not greater than about 0.70 wt % silicon, not greater than about 0.03 wt % aluminum, not greater than 0.02 wt % titanium, not greater than 0.04 wt % zirconium, between 100 and 225 ppm oxygen, not greater than about 100 ppm nitrogen, not greater than about 100 ppm sulfur, not greater than about 100 ppm phosphorus, and the balance essentially iron. The weld metals are applied using a power source with pulsed current waveform control with <5% CO2 and <2% oxygen in the shielding gas.
    Type: Application
    Filed: January 30, 2018
    Publication date: June 21, 2018
    Inventors: Douglas P. Fairchild, Mario L. Macia, Nathan E. Nissley, Raghavan Ayer, Hyun-Woo Jin, Adnan Ozekcin
  • Patent number: 9896748
    Abstract: A steel composition and method from making a dual phase steel therefrom. The dual phase steel may have carbon of about 0.05% by weight to about 0.12 wt %; niobium of about 0.005 wt % to about 0.03 wt %; titanium of about 0.005 wt % to about 0.02 wt %; nitrogen of about 0.001 wt % to about 0.01 wt %; silicon of about 0.01 wt % to about 0.5 wt %; manganese of about 0.5 wt % to about 2.0 wt %; and a total of molybdenum, chromium, vanadium and copper less than about 0.15 wt %. The steel may have a first phase consisting of ferrite and a second phase having one or more of carbide, pearlite, martensite, lower bainite, granular bainite, upper bainite, and degenerate upper bainite. A solute carbon content in the first phase may be about 0.01 wt % or less.
    Type: Grant
    Filed: January 30, 2012
    Date of Patent: February 20, 2018
    Assignee: Exxon Mobil Upstream Research Company
    Inventors: Jayoung Koo, Narasimha-Rao V. Bangaru, Swarupa Soma Bangaru, Hyun-Woo Jin, Adnan Ozekcin, Raghavan Ayer, Douglas P. Fairchild, Danny L. Beeson, Douglas S. Hoyt, James B. LeBleu, Jr., Shigeru Endo, Mitsuhiro Okatsu, Shinichi Kakihara, Moriyasu Nagae
  • Patent number: 9821401
    Abstract: Weld metals and methods for welding ferritic steels are provided. The weld metals have high strength and high ductile tearing resistance and are suitable for use in strain based pipelines. The weld metal contains retained austenite and has a cellular microstructure with cell walls containing lath martensite and cell interiors containing degenerate upper bainite. The weld metals are comprised of between 0.02 and 0.12 wt % carbon, between 7.50 and 14.50 wt % nickel, not greater than about 1.00 wt % manganese, not greater than about 0.30 wt % silicon, not greater than about 150 ppm oxygen, not greater than about 100 ppm sulfur, not greater than about 75 ppm phosphorus, and the balance essentially iron. Other elements may be added to enhance the properties of the weld metal. The weld metals are applied using a power source with current waveform control which produces a smooth, controlled welding arc and weld pool in the absence of CO2 or oxygen in the shielding gas.
    Type: Grant
    Filed: December 12, 2011
    Date of Patent: November 21, 2017
    Assignee: ExxonMobil Upstream Research Company
    Inventors: Douglas P. Fairchild, Mario L. Macia, Steven J. Ford, Nathan E. Nissley, Raghavan Ayer, Hyun-Woo Jin, Adnan Ozekcin
  • Publication number: 20150129559
    Abstract: Weld metals and methods for welding ferritic steels are provided. The weld metals have high strength and high ductile tearing resistance and are suitable for use in strain based pipelines. The weld metals are comprised of between 0.03 and 0.08 wt % carbon, between 2.0 and 3.5 wt % nickel, not greater than about 2.0 wt % manganese, not greater than about 0.80 wt % molybdenum, not greater than about 0.70 wt % silicon, not greater than about 0.03 wt % aluminum, not greater than 0.02 wt % titanium, not greater than 0.04 wt % zirconium, between 100 and 225 ppm oxygen, not greater than about 100 ppm nitrogen, not greater than about 100 ppm sulfur, not greater than about 100 ppm phosphorus, and the balance essentially iron. The weld metals are applied using a power source with pulsed current waveform control with <5% CO2 and <2% oxygen in the shielding gas.
    Type: Application
    Filed: June 24, 2013
    Publication date: May 14, 2015
    Inventors: Douglas P. Fairchild, Mario L. Macia, Nathan E. Nissley, Raghavan Ayer, Hyun-Woo Jin, Adnan Ozekcin
  • Publication number: 20140261918
    Abstract: Improved steel compositions and methods of making the same are provided. The present disclosure provides advantageous wear resistant steel. More particularly, the present disclosure provides high manganese (Mn) steel having enhanced wear resistance, and methods for fabricating high manganese steel compositions having enhanced wear resistance. The advantageous steel compositions/components of the present disclosure improve one or more of the following properties: wear resistance, ductility, crack resistance, erosion resistance, fatigue life, surface hardness, stress corrosion resistance, fatigue resistance, and/or environmental cracking resistance. In general, the present disclosure provides high manganese steels tailored to resist wear and/or erosion.
    Type: Application
    Filed: March 4, 2014
    Publication date: September 18, 2014
    Applicant: ExxonMobil Research and Engineering Company
    Inventors: HyunWoo Jin, Ning Ma, Raghavan Ayer, Russell Robert Mueller, Hak-Cheol Lee, Jong-Kyo Choi, In-Shik Suh
  • Patent number: 8691030
    Abstract: The present application describes a steel composition that provides enhanced corrosion resistance. This steel composition includes one of vanadium in an amount of 1 wt % to 9 wt %, titanium in an amount of about 1 wt % to 9 wt %, and a combination of vanadium and titanium in an amount of 1 wt % to about 9 wt %. In addition, the steel composition includes carbon in an amount of 0.03 wt % to about 0.45 wt %, manganese in an amount up to 2 wt % and silicon in an amount up to 0.45 wt %. In one embodiment, the steel composition includes a microstructure of one of the following: ferrite, martensite, tempered martensite, dual phase ferrite and martensite, and dual phase ferrite and tempered martensite. Further, the present application describes a method for processing the steel composition and use of equipment such as oil country tubular goods, fabricated with the steel composition.
    Type: Grant
    Filed: May 2, 2008
    Date of Patent: April 8, 2014
    Assignee: ExxonMobil Upstream Research Company
    Inventors: Dylan V. Pugh, Joseph C. Bondos, Shiun Ling, Raghavan Ayer, Shalawn K. Jackson, Jayoung Koo, Swarupa S. Bangaru
  • Patent number: 8637166
    Abstract: Provided are strain hardened high strength nickel based alloy welds that yield improved properties and performance in joining high strength metals. The advantageous weldments include two or more segments of ferrous or non-ferrous components, and fusion welds, friction stir welds, electron beam welds, laser beam welds, or a combination thereof bonding adjacent segments of the components together, wherein the welds comprise a strain hardened nickel based alloy weld metal composition including greater than or equal to 10 wt % Mo based on the total weight of the nickel based alloy weld metal composition. Also provided are methods for forming the welds from the nickel based alloy weld compositions. The strain hardened high strength nickel based alloy welds are useful in the oil, gas and petrochemical industry in applications for natural gas transportation and storage, oil and gas well completion and production, and oil and gas refinery and chemical plants.
    Type: Grant
    Filed: December 16, 2008
    Date of Patent: January 28, 2014
    Assignee: Exxonmobil Research and Engineering Company
    Inventors: Raghavan Ayer, Neeraj Srinivas Thirumalai, Hyun-Woo Jin, Daniel B. Lillig, Douglas Paul Fairchild, Steven Jeffrey Ford
  • Publication number: 20130292362
    Abstract: Weld metals and methods for welding ferritic steels are provided. The weld metals have high strength and high ductile tearing resistance and are suitable for use in strain based pipelines. The weld metal contains retained austenite and has a cellular microstructure with cell walls containing lath martensite and cell interiors containing degenerate upper bainite. The weld metals are comprised of between 0.02 and 0.12 wt % carbon, between 7.50 and 14.50 wt % nickel, not greater than about 1.00 wt % manganese, not greater than about 0.30 wt % silicon, not greater than about 150 ppm oxygen, not greater than about 100 ppm sulfur, not greater than about 75 ppm phosphorus, and the balance essentially iron. Other elements may be added to enhance the properties of the weld metal. The weld metals are applied using a power source with current waveform control which produces a smooth, controlled welding arc and weld pool in the absence of CO2 or oxygen in the shielding gas.
    Type: Application
    Filed: December 12, 2011
    Publication date: November 7, 2013
    Inventors: Douglas P. Fairchild, Mario L. Macia, Steven J. Ford, Nathan E. Nissley, Raghavan Ayer, Hyun-Woo Jin, Adnan Ozekcin
  • Patent number: 8426033
    Abstract: Provided are precipitation hardened high strength nickel based alloy welds that yield improved properties and performance in joining high strength metals. The advantageous weldments include two or more segments of ferrous or non-ferrous components, and fusion welds, friction stir welds, electron beam welds, laser beam welds, or a combination thereof bonding adjacent segments of the components together, wherein the welds comprise a precipitation hardened nickel based alloy weld metal composition including greater than or equal to 1.4 wt % of combined aluminum and titanium based on the total weight of the nickel based alloy weld metal composition. Also provided are methods for forming the welds from the nickel based alloy weld compositions, wherein the precipitation hardening occurs in the as-welded condition. The nickel based welds do not require a separate heat treatment step after welding to produce advantageous strength properties.
    Type: Grant
    Filed: December 16, 2008
    Date of Patent: April 23, 2013
    Assignee: ExxonMobil Research and Engineering Company
    Inventors: Raghavan Ayer, Neeraj Srinivas Thirumalai, Hyun-Woo Jin, Daniel B. Lillig, Douglas Paul Fairchild, Steven Jeffrey Ford
  • Patent number: 8286715
    Abstract: Provided are coated sleeved oil and gas well production devices and methods of making and using such coated sleeved devices. In one form, the coated sleeved oil and gas well production device includes an oil and gas well production device including one or more bodies and one or more sleeves proximal to the outer or inner surface of the one or more bodies, and a coating on at least a portion of the inner sleeve surface, outer sleeve surface, or a combination thereof, wherein the coating is chosen from an amorphous alloy, a heat-treated electroless or electro plated based nickel-phosphorous composite with a phosphorous content greater than 12 wt %, graphite, MoS2, WS2, a fullerene based composite, a boride based cermet, a quasicrystalline material, a diamond based material, diamond-like-carbon (DLC), boron nitride, and combinations thereof.
    Type: Grant
    Filed: February 22, 2010
    Date of Patent: October 16, 2012
    Assignee: ExxonMobil Research and Engineering Company
    Inventors: Jeffrey Roberts Bailey, Erika Ann Ooten Biediger, Narasimha-Rao Venkata Bangaru, Swarupa Soma Bangaru, legal representative, Adnan Ozekcin, Hyun-Woo Jin, Mehmet Deniz Ertas, Raghavan Ayer, William Curtis Elks, Charles Shiao-Hsiung Yeh, Michael David Barry, Michael Thomas Hecker
  • Publication number: 20120160363
    Abstract: Provided are high manganese containing ferrous based components and their use in oil, gas and/or petrochemical applications. In one form, the components include 5 to 40 wt % manganese, 0.01 to 3.0 wt % carbon and the balance iron. The components may optionally include one or more alloying elements chosen from chromium, nickel, cobalt, molybdenum, niobium, copper, titanium, vanadium, nitrogen, boron and combinations thereof.
    Type: Application
    Filed: December 21, 2011
    Publication date: June 28, 2012
    Applicant: EXXONMOBIL RESEARCH AND ENGINEERING COMPANY
    Inventors: Hyun Woo Jin, Raghavan Ayer, Douglas Paul Fairchild, Mario L. Macia
  • Publication number: 20120125490
    Abstract: A steel composition and method from making a dual phase steel therefrom. The dual phase steel may have carbon of about 0.05% by weight to about 0.12 wt %; niobium of about 0.005 wt % to about 0.03 wt %; titanium of about 0.005 wt % to about 0.02 wt %; nitrogen of about 0.001 wt % to about 0.01 wt %; silicon of about 0.01 wt % to about 0.5 wt %; manganese of about 0.5 wt % to about 2.0 wt %; and a total of molybdenum, chromium, vanadium and copper less than about 0.15 wt %. The steel may have a first phase consisting of ferrite and a second phase having one or more of carbide, pearlite, martensite, lower bainite, granular bainite, upper bainite, and degenerate upper bainite. A solute carbon content in the first phase may be about 0.01 wt % or less.
    Type: Application
    Filed: January 30, 2012
    Publication date: May 24, 2012
    Inventors: Jayoung Koo, Swarupa Bangaru, Hyun-Woo Jin, Adnan Ozekcin, Raghavan Ayer, Douglas P. Fairchild, Danny L. Beeson, Douglas S. Hoyt, James B. LeBleu, JR., Shigeru Endo, Mitsuhiro Okatsu, Shinichi Kakihara, Moriyasu Nagae
  • Patent number: 8168306
    Abstract: Provided are metal structures and methods of forming such structures for use in oil, gas and/or petrochemical applications that are joined with non-ferrous weld metal compositions or a high alloy weld metal compositions. The welded metal structures include two or more segments of ferrous or non-ferrous components, and fusion welds, friction stir welds or a combination thereof bonding adjacent segments of the components together, wherein the welds comprise a non-ferrous weld metal composition or a high alloy weld metal composition that is substantially different from the metal composition of the two or more components. The resultant welded structures exhibit improvements in fatigue resistance, toughness, strain capacity, strength, stress corrosion cracking resistance, and hydrogen embrittlement resistance compared to traditional iron-based weld compositions.
    Type: Grant
    Filed: September 18, 2007
    Date of Patent: May 1, 2012
    Assignee: ExxonMobil Research and Engineering Company
    Inventors: Raghavan Ayer, Neeraj S. Thirumalai, Daniel B. Lillig, Steven J. Ford, Douglas P. Fairchild
  • Patent number: 8141768
    Abstract: A method for welding and repairing cracks in metal parts is provided by subjecting the metal parts to be welded to friction stir welding and the cracks to be repaired to friction stir processing under conditions sufficient to provide a weld joint or crack repair having a preselected property or set of properties based upon the intended use of the weldment. The FSW and FSP methods are advantageous in joining and repairing metal structures and components in applications for natural gas transportation and storage, oil and gas well completion and production, and oil and gas refinery and chemical plants.
    Type: Grant
    Filed: December 21, 2006
    Date of Patent: March 27, 2012
    Assignee: ExxonMobil Research and Engineering Company
    Inventors: Steven J. Ford, Neeraj Thirumalai, James Ronald Rigby, Mark Biegler, Narasimha-Rao Venkata Bangaru, Jayoung Koo, Glen A. Vaughn, Raghavan Ayer, Douglas P. Fairchild
  • Publication number: 20110162751
    Abstract: Provided are coated petrochemical and chemical industry devices and methods of making and using such coated devices. In one form, the coated petrochemical and chemical industry device includes a petrochemical and chemical industry device including one or more bodies, and a coating on at least a portion of the one or more bodies, wherein the coating is chosen from an amorphous alloy, a heat-treated electroless or electro plated based nickel-phosphorous composite with a phosphorous content greater than 12 wt %, graphite, MoS2, WS2, a fullerene based composite, a boride based cermet, a quasicrystalline material, a diamond based material, diamond-like-carbon (DLC), boron nitride, and combinations thereof. The coated petrochemical and chemical industry devices may provide for reduced friction, wear, corrosion and other properties required for superior performance.
    Type: Application
    Filed: December 1, 2010
    Publication date: July 7, 2011
    Applicant: ExxonMobil Research and Engineering Company
    Inventors: Brian Joseph Fitzgerald, Hyun-Woo Jin, Raghavan Ayer, Yu Feng Wang
  • Publication number: 20110120723
    Abstract: The present application describes a steel composition that provides enhanced corrosion resistance. This steel composition includes one of vanadium in an amount of 1 wt % to 9 wt %, titanium in an amount of about 1 wt % to 9 wt %, and a combination of vanadium and titanium in an amount of 1 wt % to about 9 wt %. In addition, the steel composition includes carbon in an amount of 0.03 wt % to about 0.45 wt %, manganese in an amount up to 2 wt % and silicon in an amount up to 0.45 wt %. In one embodiment, the steel composition includes a microstructure of one of the following: ferrite, martensite, tempered martensite, dual phase ferrite and martensite, and dual phase ferrite and tempered martensite. Further, the present application describes a method for processing the steel composition and use of equipment such as oil country tubular goods, fabricated with the steel composition.
    Type: Application
    Filed: May 2, 2008
    Publication date: May 26, 2011
    Inventors: Dylan V. Pugh, Joseph C. Bondos, Shiun Ling, Raghavan Ayer, Shalawn K. Jackson, Narasimha-Rao V. Bangaru, Swarupa S. Bangaru, Jayoung Koo
  • Publication number: 20110042069
    Abstract: Provided are coated sleeved oil and gas well production devices and methods of making and using such coated sleeved devices. In one form, the coated sleeved oil and gas well production device includes an oil and gas well production device including one or more bodies and one or more sleeves proximal to the outer or inner surface of the one or more bodies, and a coating on at least a portion of the inner sleeve surface, outer sleeve surface, or a combination thereof, wherein the coating is chosen from an amorphous alloy, a heat-treated electroless or electro plated based nickel-phosphorous composite with a phosphorous content greater than 12 wt %, graphite, MoS2, WS2, a fullerene based composite, a boride based cermet, a quasicrystalline material, a diamond based material, diamond-like-carbon (DLC), boron nitride, and combinations thereof.
    Type: Application
    Filed: February 22, 2010
    Publication date: February 24, 2011
    Inventors: Jeffrey Roberts Bailey, Erika Ann Ooten Biediger, Narasimha-Rao Venkata Bangaru, Adnan Ozekcin, Hyun-Woo Jin, Mehmet Deniz Ertas, Raghavan Ayer, William Curtis Elks, Charles Shiao-Hsiung Yeh, Michael David Barry, Michael Thomas Hecker, Swarupa Soma Bangaru
  • Publication number: 20100136369
    Abstract: Provided are steel structures methods of making such steel structures including structural steel components bonded by friction stir weldments with advantageous microstructures to yield improved weldment strength and weldment toughness. In one form of the present disclosure, the steel structure includes: two or more structural steel components produced by conventional melting or secondary refining practices and friction stir weldments bonding faying surfaces of the components together, wherein the chemistry and grain size of the starting structural steel satisfies one or more of the following criteria: a) 0.02 wt %<Ti+Nb<0.12 wt %, b) 0.7<Ti/N<3.5, c) 0.5 wt %<Mo+W+Cr+Cu+Co+Ni<1.75 wt %, d) 0.01 wt %<TiN+NbC+TiO/MgO<0.
    Type: Application
    Filed: November 17, 2009
    Publication date: June 3, 2010
    Inventors: Raghavan Ayer, Douglas Paul Fairchild, Steven Jeffrey Ford, Hyun-Woo Jin, Adnan Ozekcin