Patents by Inventor Donald D. Reitsma

Donald D. Reitsma 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).

  • Wellbore annular pressure control system and method using gas lift in drilling fluid return line
    Patent number: 9376875
    Abstract: A system and method include pumping drilling fluid through a drill string extended into a wellbore extending below the bottom of a body of water, out the bottom of the drill string and into the wellbore annulus. Fluid is discharged from the annulus into a riser and a discharge conduit. The riser is disposed above the top of the wellbore and extends to the water surface. The discharge conduit couples to the riser and includes a controllable fluid choke. A fluid return line is coupled to an outlet of the choke and extends to the water surface. Gas under pressure is pumped into the return line at a selected depth below the water surface. The controllable fluid choke may be operated to maintain a selected drilling fluid level in the riser, the selected fluid level being a selected distance below the water surface.
    Type: Grant
    Filed: April 29, 2013
    Date of Patent: June 28, 2016
    Assignee: SMITH INTERNATIONAL, INC.
    Inventors: Donald D. Reitsma, Ossama R. Sehsah, Yawan Couturier
  • WELLBORE ANNULAR PRESSURE CONTROL SYSTEM AND METHOD USING GAS LIFT IN DRILLING FLUID RETURN LINE
    Publication number: 20150083429
    Abstract: A system and method include pumping drilling fluid through a drill string extended into a wellbore extending below the bottom of a body of water, out the bottom of the drill string and into the wellbore annulus. Fluid is discharged from the annulus into a riser and a discharge conduit. The riser is disposed above the top of the wellbore and extends to the water surface. The discharge conduit couples to the riser and includes a controllable fluid choke. A fluid return line is coupled to an outlet of the choke and extends to the water surface. Gas under pressure is pumped into the return line at a selected depth below the water surface. The controllable fluid choke may be operated to maintain a selected drilling fluid level in the riser, the selected fluid level being a selected distance below the water surface.
    Type: Application
    Filed: April 29, 2013
    Publication date: March 26, 2015
    Inventors: Donald D. Reitsma, Ossama R. Sehsah, Yawan Couturier