Measurement while drilling

About: Measurement while drilling is a research topic. Over the lifetime, 2109 publications have been published within this topic receiving 25505 citations.

Closed loop drilling system

Abstract: The present invention provides a closed-loop drilling system for drilling oilfield boreholes. The system includes a drilling assembly with a drill bit, a plurality of sensors for providing signals relating to parameters relating to the driling assembly, borehole, and formations around the drilling assembly. Processors in the drilling system process sensors signal and compute drilling parameters based on models and programmed instructions provided to the drilling system that will yield further drilling at enhanced drilling rates and with extended drilling assembly life. The drilling system then automatically adjusts the drilling parameters for continued drilling. The system continually or periodically repeats this process during the drilling operations. The drilling system also provides severity of certain dysfunctions to the operator and a means for simulating the drilling assembly behavior prior to effecting changes in the drilling parameters.

Drilling system with sensors for determining properties of drilling fluid downhole

Abstract: The present invention provides a drilling system for drilling oilfield boreholes or wellbores utilizing a drill string having a drilling assembly conveyed downhole by a tubing (usually a drill pipe or coiled tubing). The drilling assembly includes a bottom hole assembly (BHA) and a drill bit. The bottom hole assembly preferably contains commonly used measurement-while-drilling sensors. The drill string also contains a variety of sensors for determining downhole various properties of the drilling fluid. Sensors are provided to determine density, viscosity, flow rate, clarity, compressibility, pressure and temperature of the drilling fluid at one or more downhole locations. Chemical detection sensors for detecting the presence of gas (methane) and H2S are disposed in the drilling assembly. Sensors for determining fluid density, viscosity, pH, solid content, fluid clarity, fluid compressibility, and a spectroscopy sensor are also disposed in the BHA. Data from such sensors may be processed downhole and/or at the surface. Corrective actions are taken based upon the downhole measurements at the surface which may require altering the drilling fluid composition, altering the drilling fluid pump rate or shutting down the operation to clean wellbore. The drilling system contains one or more models, which may be stored in memory downhole or at the surface. These models are utilized by the downhole processor and the surface computer to determine desired fluid parameters for continued drilling. The drilling system is dynamic, in that the downhole fluid sensor data is utilized to update models and algorithms during drilling of the wellbore and the updated models are then utilized for continued drilling operations.

Method and system for predicting performance of a drilling system for a given formation

Abstract: A method and apparatus for predicting the performance of a drilling system for the drilling of a well bore in a given formation includes generating a geology characteristic of the formation per unit depth according to a prescribed geology model, obtaining specifications of proposed drilling equipment for use in the drilling of the well bore, and predicting a drilling mechanics in response to the specifications as a function of the geology characteristic per unit depth according to a prescribed drilling mechanics model. Responsive to a predicted drilling mechanics, a controller controls a parameter in the drilling of the well bore. The geology characteristic includes at least rock strength. The specifications include at least a bit specification of a recommended drill bit. Lastly, the predicted drilling mechanics include at least one of bit wear, mechanical efficiency, power, and operating parameters. A display is provided for generating a display of the geology characteristic and predicted drilling mechanics per unit depth, including either a display monitor or a printer.

System for drilling deviated boreholes

Abstract: Improved techniques are provided for drilling a deviated borehole through earth formations utilizing a rotary bit powered by a drill motor, and for obtaining information regarding the borehole or earth formations while drilling An inclinometer is positioned below the drill motor and within a sealed cavity of a housing fixed to a drill motor sub, and a transmitter within the sealed cavity forwards acoustic or radial wave signals to a receiver provided in a measurement-while-drilling tool The MWD tool may be provided within a non-magnetic portion of the drill string, and further houses an accelerometer for sensing borehole direction Both borehole inclination and directional signals are transmitted to the surface by the MWD tool, and the drilling trajectory is altered in response to the signals

Downhole tool apparatus with non-metallic components and methods of drilling thereof

Abstract: A downhole tool apparatus and methods of drilling the apparatus. The apparatus may include, but is not limited to, packers and bridge plugs utilizing non-metallic slip components. The non-metallic material may include engineering grade plastics. In one embodiment, the slips are separate and held in place in an initial position around the slip wedge by a retainer ring. In another embodiment, the slips are integrally formed with a ring portion which holds the slips in the initial position around the wedge; in this embodiment, the ring portion is made of a fracturable non-metallic material which fractures during a setting operation to separate the slips. Methods of drilling out the apparatus without significant variations in the drilling speed and weight applied to the drill bit may be employed. Alternative drill bit types, such as polycrystalline diamond compact (PDC) bits may also be used.