The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Nov. 20, 2018
Filed:
Aug. 09, 2016
Smith International, Inc., Houston, TX (US);
Donald G. Reitsma, Katy, TX (US);
Ossama Ramzi Sehsah, Katy, TX (US);
Yawan Couturier, Katy, TX (US);
Smith International, Inc., Houston, TX (US);
Abstract
A method for maintaining pressure in a wellbore drilled from a drilling platform floating on a body of water includes the steps of pumping fluid at a determined flow rate into a drill string disposed in a wellbore and measuring fluid pressure within a fluid discharge line of fluid returning from the wellbore. The fluid discharge line has a variable length corresponding to an elevation of the floating platform above the bottom of the body of water. The wellbore pressure is determined at a selected depth in the wellbore or at a selected position along a drilling riser or variable length portion of the fluid discharge line using known parameters/methods. The determined wellbore pressure is adjusted for changes in length of the fluid discharge line corresponding to changes in the elevation of the floating platform relative to the bottom of the body of water. A backpressure system may be operated to maintain the adjusted determined wellbore pressure at a selected (or set point) value by applying backpressure to the wellbore.