Patents by Inventor Parul Walia

Parul Walia 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: 9156136
    Abstract: A method is disclosed for leaching a polycrystalline diamond (PCD) cutter element. In an embodiment, the method includes suspending the PCD cutter element above a liquid acid bath. In addition, the method includes elevating the temperature of the liquid acid bath above ambient conditions to transition at least some of the liquid acid bath to acid vapors. Further, the method includes elevating the pressure of the acid vapors above ambient conditions. Still further, the method includes exposing the PCD cutter element to the acid vapors.
    Type: Grant
    Filed: November 6, 2013
    Date of Patent: October 13, 2015
    Assignee: NATIONAL OILWELL VARCO, L.P.
    Inventors: Guodong Zhan, Walter R. Rothrock, Parul Walia Dhall, Michael S. Nixon, Terry R. Matthias
  • Publication number: 20150052821
    Abstract: A bond matrix for metal bonded abrasive tools includes a metal bond system, porosity and an optional filler. Tools according to embodiments of the invention exhibit long tool life, produce an acceptable quality of cut and can have self-dressing properties. The bond matrix can be used, for example, in abrasives tools configured for the electronics industry, such as 1A8 wheels for slicing ball grid arrays (BGAs) and other such slicing operations.
    Type: Application
    Filed: November 5, 2014
    Publication date: February 26, 2015
    Inventors: Parul Walia, Srinivasan Ramanath, Richard W. J. Hall
  • Patent number: 8894731
    Abstract: Abrasive articles possessing a highly open (porous) structure and uniform abrasive grit distribution are disclosed. The abrasive articles are fabricated using a metal matrix (e.g., fine nickel, tin, bronze and abrasives). The open structure is controlled with a porosity scheme, including interconnected porosity (e.g., formed by leaching of dispersoid), closed porosity (e.g., induced by adding a hollow micro-spheres and/or sacrificial pore-forming additives), and/or intrinsic porosity (e.g., controlled via matrix component selection to provide desired densification). In some cases, manufacturing process temperatures for achieving near full density of metal bond with fillers and abrasives, are below the melting point of the filler used, although sacrificial fillers may be used as well. The resulting abrasive articles are useful in high performance cutting and grinding operations, such as back-grinding silicon, alumina titanium carbide, and silicon carbide wafers to very fine surface finish values.
    Type: Grant
    Filed: October 1, 2007
    Date of Patent: November 25, 2014
    Assignees: Saint-Gobain Abrasives, Inc., Saint-Gobain Abrasifs
    Inventors: Srinivasan Ramanath, Parul Walia
  • Patent number: 8882868
    Abstract: A bond matrix for metal bonded abrasive tools includes a metal bond system, porosity and an optional filler. Tools according to embodiments of the invention exhibit long tool life, produce an acceptable quality of cut and can have self-dressing properties. The bond matrix can be used, for example, in abrasives tools configured for the electronics industry, such as 1A8 wheels for slicing ball grid arrays (BGAs) and other such slicing operations.
    Type: Grant
    Filed: June 30, 2009
    Date of Patent: November 11, 2014
    Assignees: Saint-Gobain Abrasives, Inc., Saint-Gobain Abrasifs
    Inventors: Parul Walia, Srinivasan Ramanath, Richard W. Hall
  • Publication number: 20140123565
    Abstract: A system for leaching a polycrystalline diamond (PCD) cutter element having a PCD table and a substrate, the system including a housing having an open first end and a closed second end and a lid removably and sealingly attached the first end of the housing. The housing and the lid define an inner chamber extending between the first end and the second end, and the inner chamber is configured to receive and hold a volume of liquid acid therein. In addition, the system includes a cutter element holder disposed within the inner chamber, wherein the PCD cutter element is suspended above the volume of liquid acid in the inner chamber with the holder.
    Type: Application
    Filed: November 6, 2013
    Publication date: May 8, 2014
    Applicant: National Oilwell Varco, L.P.
    Inventors: Guodong Zhan, Walter R. Rothrock, Parul Walia Dhall, Michael S. Nixon, Terry R. Matthias
  • Publication number: 20100000159
    Abstract: A bond matrix for metal bonded abrasive tools includes a metal bond system, porosity and an optional filler. Tools according to embodiments of the invention exhibit long tool life, produce an acceptable quality of cut and can have self-dressing properties. The bond matrix can be used, for example, in abrasives tools configured for the electronics industry, such as 1A8 wheels for slicing ball grid arrays (BGAs) and other such slicing operations.
    Type: Application
    Filed: June 30, 2009
    Publication date: January 7, 2010
    Applicants: SAINT-GOBAIN ABRASIVES, INC., SAINT-GOBAIN ABRASIFS
    Inventors: Parul Walia, Srinivasan Ramanath, Richard W. Hall
  • Publication number: 20090084042
    Abstract: Abrasive articles possessing a highly open (porous) structure and uniform abrasive grit distribution are disclosed. The abrasive articles are fabricated using a metal matrix (e.g., fine nickel, tin, bronze and abrasives). The open structure is controlled with a porosity scheme, including interconnected porosity (e.g., formed by leaching of dispersoid), closed porosity (e.g., induced by adding a hollow micro-spheres and/or sacrificial pore-forming additives), and/or intrinsic porosity (e.g., controlled via matrix component selection to provide desired densification). In some cases, manufacturing process temperatures for achieving near full density of metal bond with fillers and abrasives, are below the melting point of the filler used, although sacrificial fillers may be used as well. The resulting abrasive articles are useful in high performance cutting and grinding operations, such as back-grinding silicon, alumina titanium carbide, and silicon carbide wafers to very fine surface finish values.
    Type: Application
    Filed: October 1, 2007
    Publication date: April 2, 2009
    Applicants: Saint-Gobain Abrasives, Inc., Saint-Gobain Abrasifs Technologie et Services, S.A.S
    Inventors: Srinivasan Ramanath, Parul Walia