Apparatus and methods for optimizing a stick-slip algorithm for controlling a driver of a drill string. A method may include commencing operation of a control system for controlling the driver. The control system may have a processor and a memory storing a computer program code, which may include the stick-slip algorithm. The operating control system may receive a plurality of different numerical parameters, and for each of the different numerical parameters, incorporate the numerical parameter into the stick-slip algorithm and execute the stick-slip algorithm to determine a control command that causes the driver to rotate the drill string to perform drilling operations while reducing amplitude of rotational waves travelling along the drill string.

A method for operating a drilling plant machine includes providing a drilling plant machine which includes a sensor which measures a parameter which is indicative of a jarring load acting on the drilling plant machine from a drill string, providing a set of values representing readings from the sensor, identifying a jarring event, and determining a magnitude of the parameter from the set of values.

A method for operating a drilling plant machine includes providing a drilling plant machine which includes a sensor which measures a parameter which is indicative of a jarring load acting on the drilling plant machine from a drill string, providing a set of values representing readings from the sensor, identifying a jarring event, and determining a magnitude of the parameter from the set of values.

Unwanted oscillations of a drill string while a borehole is being drilled are limited by adjusting a drilling parameter. Measurements related to oscillations of the drill string can be extrapolated by calculation to a position of interest along the drill string using a mode identified from one or more determined modes and a stability criterion that models the drill string. The stability criterion includes a specific modal damping for each of the one or more determined modes. The position of interest may correspond to a location of a tool or component that may be damaged by the unwanted oscillations. If the tool or component can be damaged by the oscillations as calculated, then the drilling parameter is adjusted to limit those oscillations.

Systems and methods for reducing or eliminating stick-slip are described. The system includes a controller and a drawworks. The controller is configured to collect downhole information, detect one or more stick-slip conditions, determine correlative relationships, model a stick-slip region, generate a control algorithm for top drive RPM and WOB that avoids a stick-slip region, determine a WOB autodriller set point for a particular top drive RPM using the control algorithm and provide one or more operational control signals that limit the WOB to the WOB autodriller set point for the particular top drive RPM. The drawworks is configured to receive the one or more operational control signals from the controller, and limit the WOB so that the WOB does not exceed the WOB autodriller set point for the particular top drive RPM.

Systems and methods for reducing or eliminating stick-slip are described. The system includes a controller and a drawworks. The controller is configured to collect downhole information, detect one or more stick-slip conditions, determine correlative relationships, model a stick-slip region, generate a control algorithm for top drive RPM and WOB that avoids a stick-slip region, determine a WOB autodriller set point for a particular top drive RPM using the control algorithm and provide one or more operational control signals that limit the WOB to the WOB autodriller set point for the particular top drive RPM. The drawworks is configured to receive the one or more operational control signals from the controller, and limit the WOB so that the WOB does not exceed the WOB autodriller set point for the particular top drive RPM.

A method for performing a coiled-tubing process, the method having the steps of performing a coiled-tubing process using a fluid-lubricant composition that includes: a sulfurized component, and a chlorinated component, wherein the sulfurized component is a sulfurized C8 to C14 olefin, wherein the chlorinated component is a chlorinated fatty ester, a chlorinated paraffin, or a chlorinated olefin; and introducing the fluid-lubricant composition into a subterranean wellbore casing.

A method for performing a coiled-tubing process, the method having the steps of performing a coiled-tubing process using a fluid-lubricant composition that includes: a sulfurized component, and a chlorinated component, wherein the sulfurized component is a sulfurized C8 to C14 olefin, wherein the chlorinated component is a chlorinated fatty ester, a chlorinated paraffin, or a chlorinated olefin; and introducing the fluid-lubricant composition into a subterranean wellbore casing.

A drilling device having a drill drive, a positioning means, a receiving part, a clamping means, and a control unit. The receiving part holds a first drill rod element with a first thread region. The clamping means is positioned on the drill drive for holding at least a second drill rod element having a second thread region. The control unit actuates the drill drive and the positioning means to screw the first and second thread regions together. A distance measuring means detects an adjustment distance of the drill drive along a guide as an actual value. The control unit determines an adjustment distance as a nominal value from a detected revolution speed of the drill drive during screwing and a predetermined thread constant. The control unit determines a difference from the nominal and actual values, and uses the difference to adjust the drill drive and/or the positioning means.

A drilling device having a drill drive, a positioning means, a receiving part, a clamping means, and a control unit. The receiving part holds a first drill rod element with a first thread region. The clamping means is positioned on the drill drive for holding at least a second drill rod element having a second thread region. The control unit actuates the drill drive and the positioning means to screw the first and second thread regions together. A distance measuring means detects an adjustment distance of the drill drive along a guide as an actual value. The control unit determines an adjustment distance as a nominal value from a detected revolution speed of the drill drive during screwing and a predetermined thread constant. The control unit determines a difference from the nominal and actual values, and uses the difference to adjust the drill drive and/or the positioning means.