Abstract: A method of monitoring the drilling of a wellbore having a drilling fluid that circulates in the wellbore during drilling, comprises: Extracting a plurality of gaseous compounds from a sample of drilling fluid exiting the wellbore, Measuring a quantity y(i) of at least a group of compounds, each group comprises comprising at least one extracted gaseous compound, Determining, from the measured quantity y(i) and an extraction coefficient ?(i) associated to each group, the content x(i) of each group of gaseous compounds present in the sample of drilling fluid, Deriving a drilling indicator from the content x(i) of at least one group of gaseous compounds.

Abstract: The disclosure relates to a method of monitoring the drilling of a wellbore, wherein a drilling fluid circulates in the wellbore during drilling, the method comprising: Extracting (106) a plurality of gaseous compound from a sample of drilling fluid exiting the wellbore, Measuring (108) a quantity y(i) of at least a group of compounds, wherein each group comprises at least one extracted gaseous compound, Determining (110), from the measured quantity y(i) and an extraction coefficient ?(i) associated to each group, the content x(i) of each group of gaseous compounds present in the sample of drilling fluid, Deriving (116) a drilling indicator from the content x(i) of at least one group of gaseous compounds,

Abstract: A method for selecting a drill bit, the method includes obtaining a plurality of data of a first well within an earth formation, correlating the plurality of data of the first well to identify a set of reduced variables of the plurality of data, segmenting the reduced set of the plurality of data into a plurality of facies based on one of drillability and steerability, performing analysis of drilling performance of each of the plurality of facies, and selecting a drill bit based on the drilling performance.

Abstract: A drilling system and method are provided. The drilling system comprising a tool body, a drill bit, a mechanism for applying weight to the drill bit (“WOB”), and a control system for controlling the rate of rotation of the drill bit (“RPM”) and the weight applied to the bit during drilling. The control system is configurable to a first mode in which RPM and WOB are controlled to maintain power on the drill bit at a predetermined maximum, and a second mode in which RPM and WOB are controlled to maintain a predetermined depth of cut (“DOC”). In use, the control system is adapted to switch between the first and second modes depending on drilling conditions.

Abstract: A drilling system and method are provided. The drilling system comprising a tool body, a drill bit, a mechanism for applying weight to the drill bit (“WOB”), and a control system for controlling the rate of rotation of the drill bit (“RPM”) and the weight applied to the bit during drilling. The control system is configurable to a first mode in which RPM and WOB are controlled to maintain power on the drill bit at a predetermined maximum, and a second mode in which RPM and WOB are controlled to maintain a predetermined depth of cut (“DOC”). In use, the control system is adapted to switch between the first and second modes depending on drilling conditions.

Abstract: An apparatus for removing debris from a well is provided. The apparatus comprises a tool body having a head, a chamber, a connector, a conduit, and a filter. The head has an opening and comprises protrusions extending from the outer surface for moving debris. The chamber is in the tool body to store debris. The connector is for attaching the tool body to a drilling system. The conduit is connected to the opening in the head to convey debris and fluid from the well to the chamber. The filter is in the tool body to limit the size of the particles that can pass into the drilling system from the chamber. In use, fluid flow and the protrusions move the debris from the well and through the apparatus.

Abstract: A roll stabilised unit comprises a tool housing (30) rotatably mounted within a tool collar (28), the tool housing (30) having rotatably mounted thereon a first impeller (36), a variable torque transmission arrangement (38) being provided to allow the torque transmitted from the first impeller (36) to the housing (30) to be controlled, and a second impeller (40) fixed relative to the housing (30) so as to be rotatable with the housing (30).