Patents by Inventor Jan Edgar Marshall

Jan Edgar Marshall 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).

  • Matrix fixed cutter drill bits and methods for manufacturing same
    Patent number: 9631435
    Abstract: A fixed cutter drill bit for drilling a borehole in earthen formations includes a blank assembly and a matrix crown fixably mounted to the blank assembly. The blank assembly includes an annular mandrel and a plurality of elongate studs fixably coupled to the mandrel. The mandrel has a first end distal the crown and a second end engaging the crown. In addition, the mandrel includes a plurality of bores extending axially from the second end. Each elongate stud has a first end disposed within one of the bores and a second end disposed in the crown distal the mandrel.
    Type: Grant
    Filed: December 10, 2013
    Date of Patent: April 25, 2017
    Assignee: NATIONAL OILWELL DHT, L.P.
    Inventors: Michael Garner, Jan Edgar Marshall, Harold A. Sreshta
  • Reinforced stators and fabrication methods
    Patent number: 9309767
    Abstract: A stator for a progressive cavity pump or motor comprises a tubular housing having a central axis. In addition, the stator comprises a stator insert coaxially disposed within the housing. The stator insert has a radially outer surface that engages the housing and a radially inner surface defining a helical-shaped through bore extending axially through the stator insert. The stator insert includes an insert body and an insert liner attached to the insert body. The insert body is radially positioned between the housing and the insert liner. The insert body comprises a reinforcement structure and a plurality of voids dispersed within the reinforcement structure.
    Type: Grant
    Filed: August 15, 2011
    Date of Patent: April 12, 2016
    Assignee: NATIONAL OILWELL VARCO, L.P.
    Inventors: Harold A. Sreshta, Jiinjen Albert Sue, Stefan M. Butuc, Jan Edgar Marshall
  • MATRIX FIXED CUTTER DRILL BITS AND METHODS FOR MANUFACTURING SAME
    Publication number: 20150159440
    Abstract: A fixed cutter drill bit for drilling a borehole in earthen formations includes a blank assembly and a matrix crown fixably mounted to the blank assembly. The blank assembly includes an annular mandrel and a plurality of elongate studs fixably coupled to the mandrel. The mandrel has a first end distal the crown and a second end engaging the crown. In addition, the mandrel includes a plurality of bores extending axially from the second end. Each elongate stud has a first end disposed within one of the bores and a second end disposed in the crown distal the mandrel.
    Type: Application
    Filed: December 10, 2013
    Publication date: June 11, 2015
    Inventors: Michael Garner, Jan Edgar Marshall, Harold A. Sreshta
  • Reinforced Stators and Fabrication Methods
    Publication number: 20130149182
    Abstract: A stator for a progressive cavity pump or motor comprises a tubular housing having a central axis. In addition, the stator comprises a stator insert coaxially disposed within the housing. The stator insert has a radially outer surface that engages the housing and a radially inner surface defining a helical-shaped through bore extending axially through the stator insert. The stator insert includes an insert body and an insert liner attached to the insert body. The insert body is radially positioned between the housing and the insert liner. The insert body comprises a reinforcement structure and a plurality of voids dispersed within the reinforcement structure.
    Type: Application
    Filed: August 15, 2011
    Publication date: June 13, 2013
    Applicant: NATIONAL OILWELL VARCO, L.P.
    Inventors: Harold A. Sreshta, Jiinjen Albert Sue, Stefan M. Butuc, Jan Edgar Marshall