Downhole downlinking system employing a differential pressure transducer

#None.

#The present invention relates generally to a downhole downlinking system for receiving data and/or commands transmitted from the surface to a downhole tool deployed in a drill string. More particularly, exemplary embodiments of this invention relate to a downlinking system employing a differential transducer.

#Oil and gas well drilling operations commonly make use of logging while drilling (LWD) sensors to acquire logging data as the well bore is being drilled. This data may provide information about the progress of the drilling operation or the earth formations surrounding the well bore. Significant benefit may be obtained by improved control of downhole sensors from the rig floor or from remote locations. For example, the ability to send commands to downhole sensors that selectively activate the sensors can conserve battery life and thereby increase the amount of downhole time a sensor is useful.

#For a more complete understanding of the present invention, and the advantages thereof, reference is now made to the following descriptions taken in conjunction with the accompanying drawings, in which:

#FIG. 1 depicts a drilling rig on which exemplary embodiments of the present invention may be deployed.

#FIGS. 2A and 2B depict fully assembled and partially exploded views of a portion of the downhole tool shown on FIG. 1.

#Referring first to FIGS. 1 through 5, it will be understood that features or aspects of the embodiments illustrated may be shown from various views. Where such features or aspects are common to particular views, they are labeled using the same reference numeral. Thus, a feature or aspect labeled with a particular reference numeral on one view in FIGS. 1 through 5 may be described herein with respect to that reference numeral shown on other views.

#FIG. 1 illustrates a drilling rig 10 suitable for the deployment of exemplary embodiments of the present invention. In the exemplary embodiment shown on FIG. 1, a semisubmersible drilling platform 12 is positioned over an oil or gas formation (not shown) disposed below the sea floor 16. A subsea conduit 18 extends from deck 20 of platform 12 to a wellhead installation 22. The platform may include a derrick and a hoisting apparatus for raising and lowering the drill string 30, which, as shown, extends into borehole 40 and includes a drill bit 32, a steering tool 50, and a downhole tool 100 including a downlinking system 120 in accordance with the present invention. The downlinking system 120 may be in electronic communication, for example, with the steering tool 50 and may be disposed to receive encoded commands from the surface and transmit those encoded commands to the steering tool 50. The drill string 30 may also include various other electronic devices disposed to be in electronic communication with the downlinking system 120, e.g., including a telemetry system, additional sensors for sensing downhole characteristics of the borehole and the surrounding formation, and microcontrollers deployed in other downhole measurement tools. The invention is not limited in these regards.

#It will be understood by those of ordinary skill in the art that methods and apparatuses in accordance with this invention are not limited to use with a semisubmersible platform 12 as illustrated in FIG. 1. This invention is equally well suited for use with any kind of subterranean drilling operation, either offshore or onshore.