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:
Mar. 05, 2002
Filed:
Jun. 22, 2000
Bruno Best, Rijswijk, NL;
Shell Oil Company, Houston, TX (US);
Abstract
A drilling system for drilling a borehole into an earth formation is provided. The drilling system comprises a drill string extending into the borehole whereby an annular space is formed between the drill string and the borehole wall and the annular space contains a body of fluid. The drill string includes a longitudinal fluid passage having an outlet opening at the lower end part of the drill string, a device for selectively pumping drilling fluid via the passage and outlet opening into the body of fluid, and a fluid discharge conduit for discharging fluid from the body of fluid. The drilling system further comprises a device for controlling the fluid pressure in the body of fluid when the pumping device is inoperative to pump drilling fluid into the body of fluid.