Abstract: A method of optimizing drilling ramp-up is provided herein. More specifically, a method of ramping up a drilling operation from a static condition (0, 0) to optimum drilling parameter values (WOB*, RPM*) is provided. The method includes identifying a set of drilling control variables used in forming the wellbore. Examples include weight-on-bit (WOB) and rate of penetration (RPM). The method additionally includes selecting desired control variable values for a first identified drilling stage. The values may be generically referred to as (V1, V2). The method also includes increasing the drilling control variables from (0, 0) to pre-defined drilling control variable values (V1, V2). Preferably, V1 is a WOB value while V2 is a rotation speed value (RPM). The method also comprises monitoring a performance index (PI), wherein (PI) is a combination of torque (TQ) and penetration rate (RPM).

Abstract: A system for drilling a well comprises a drill string in a wellbore having a bit at a distal end thereof. At least one sensor measures a drilling parameter. A computer controller has a set of instructions stored therein to process the measured drilling parameter over a drilled interval to calculate, in substantially real time, an updated friction slope and an updated worn bit slope and to calculate an updated drilling parameter for at least a portion of the well-based on the updated friction slope and the updated worn bit slope.

Abstract: A method of processing downhole measurement data includes: receiving formation measurement data generated by a downhole tool during a logging-while drilling operation over a selected time period; receiving a measured depth corresponding to the selected time period based on data taken at a surface location; receiving tool rotation data generated by measurements of a rotational rate of the downhole tool taken by a downhole sensor during the selected time period; calculating a new depth of the tool as a function of time over the selected time period based on a relationship between the tool rotation data and the measured depth; and correcting an original depth of the measurement data with the new depth.

Abstract: An inground isolator and associated method can provide an electrically isolated break in a drill string using electrical insulating members/isolators that are supported by a housing. During drill string operations, the isolators are subject only compressive forces responsive to both extension (pushing) and retraction (pulling) by the drill string. The isolators can be formed from an electrically insulating material such as a ceramic material. An interchangeable inground tool system is described which integrally serves to provide an electrically isolating gap in the drill string.

Abstract: An apparatus for estimating at least one of a dynamic motion of a portion of interest of a drill string and a static parameter associated with the portion of interest, the apparatus having: a plurality of sensors operatively associated with the drill string at at least one location other than the portion of interest; and a processing system coupled to the plurality of sensors, the processing system configured to estimate at least one of the dynamic motion and the static parameter using a measurement from the plurality of sensors as input.

Abstract: A method for predicting the rate of penetration (ROP) of a drill bit drilling a well bore through intervals of rock of a subterranean formation is provided based on determined relationships between a bit-specific coefficient of sliding friction ? and mechanical efficiency EFFM and confined compressive strength CCS over a range of confined compressive strengths CCS. Confined compressive strength CCS is estimated for intervals of rock through which the drill bit is to be used to drill a well bore. The rate of penetration ROP is then calculated utilizing the estimates of confined compressive strength CCS and those determined relationships.

Abstract: A method of performing gravity surveys in a wellbore is described including performing a time-lapse measurement in a monitoring well in the vicinity of injector wellbores, determining a depth for which the difference of the time lapse measurements changes sign or crosses zero as depth of the anomaly; and using said measurements at other depth points to further determine one or more parameters relating to the location and/or size of a density anomaly caused by injecting fluids through said injector wellbores, thus enabling the sweep of an injected fluid including the occurrence of fingering in the formation.

Abstract: A method for predicting the rate of penetration (ROP) of a drill bit drilling a well bore through intervals of rock of a subterranean formation is provided. The method uses an equation based upon specific energy principles. A relationship is determined between a bit-specific coefficient of sliding friction ? and confined compressive strength CCS over a range of confined compressive strengths CCS. Similarly, another relationship for the drill bit is determined between mechanical efficiency EFFM and confined compressive strength CCS over a range of confined compressive strengths CCS. Confined compressive strength CCS is estimated for intervals of rock through which the drill bit is to be used to drill a well bore.

Abstract: The present invention is a system and method for generating an alarm relative to effective longitudinal behavior of a drill bit fastened to the end of a drill string driven in rotation in a well by a driving device situated at the surface, using a physical model of the drilling process based on general mechanics equations. The following steps are carried out: the model is reduced so to retain only pertinent modes, at least two values Rf and Rwob are calculated, Rf being a function of the principal oscillation frequency of weight on hook WOH divided by the average instantaneous rotating speed at the surface, Rwob being a function of the standard deviation of the signal of the weight on bit WOB estimated by the reduced longitudinal model from measurement of the signal of the weight on hook WOH, divided by the average weight on bit WOB0, defined from the weight of the string and the average weight on hook. Any danger from the longitudinal behavior of the drill bit is determined from the values of Rf and Rwob.