A formation tester for use in a subterranean well can include a probe which extends outward into contact with an earth formation, and an adjustable flow control device which limits an extension pressure applied to extend the probe. A method of testing a subterranean formation can include positioning a formation tester in a wellbore, extending a probe of the formation tester outward into contact with the formation, and limiting a force applied by the probe to the formation, the limiting being performed by variable actuation of a flow control device downhole. Another formation tester can include a probe which extends outward into contact with an earth formation, with a force applied by the probe to the formation being remotely adjustable downhole.

A method for wellbore directional drilling includes selecting a starting and stopping spatial position of at least one portion of the wellbore. A sequence of sliding and rotary drilling operations within the portion is determined to calculate a wellbore trajectory. The sequence has at least one drilling operating parameter. The operations include a constraint on the drilling operating parameter or the calculated trajectory. The calculated trajectory includes a projected steering response of a steerable motor in response to the at least one drilling operating parameter. Drilling the portion of the wellbore is started. A spatial position of the wellbore during drilling is determined at at least one point intermediate the starting and stopping positions. Using a relationship between the projected steering response and the drilling operating parameter, the drilling parameter and/or the constraint are adjusted based on the measured spatial position and the stopping spatial position.

A method for wellbore directional drilling includes selecting a starting and stopping spatial position of at least one portion of the wellbore. A sequence of sliding and rotary drilling operations within the portion is determined to calculate a wellbore trajectory. The sequence has at least one drilling operating parameter. The operations include a constraint on the drilling operating parameter or the calculated trajectory. The calculated trajectory includes a projected steering response of a steerable motor in response to the at least one drilling operating parameter. Drilling the portion of the wellbore is started. A spatial position of the wellbore during drilling is determined at at least one point intermediate the starting and stopping positions. Using a relationship between the projected steering response and the drilling operating parameter, the drilling parameter and/or the constraint are adjusted based on the measured spatial position and the stopping spatial position.

Systems and methods include a computer-implemented method for providing a predictive pressure protection system. Flare sources, performance limits, and relationships between control valves and relief valves are established. A flare simulator is generated using piping isometric drawings. An emergency event is monitored, and information for the emergency event is filtered based on a control valve limit breach. Event start and finish time periods are divided into cases representing smaller time frames. Source max loads are determined for each case, and each case is run through the flare simulator. Flare/relief valve performance indicators are determined based on the source max loads after running each case.

Systems and methods include a computer-implemented method for providing a predictive pressure protection system. Flare sources, performance limits, and relationships between control valves and relief valves are established. A flare simulator is generated using piping isometric drawings. An emergency event is monitored, and information for the emergency event is filtered based on a control valve limit breach. Event start and finish time periods are divided into cases representing smaller time frames. Source max loads are determined for each case, and each case is run through the flare simulator. Flare/relief valve performance indicators are determined based on the source max loads after running each case.

First time-based data, indicative of a first parameter, varies in value with respect to time and is associated with a drilling operation utilized to construct a well extending into a subterranean formation. A moving window transform of second time-based data is performed to generate a three-dimensional expression of frequency and amplitude of the first parameter or a second parameter. The second time-based data is based on the first time-based data. The second parameter varies in value with respect to time and is dependent upon the first parameter. The drilling operation is assessed based on the expression.

First time-based data, indicative of a first parameter, varies in value with respect to time and is associated with a drilling operation utilized to construct a well extending into a subterranean formation. A moving window transform of second time-based data is performed to generate a three-dimensional expression of frequency and amplitude of the first parameter or a second parameter. The second time-based data is based on the first time-based data. The second parameter varies in value with respect to time and is dependent upon the first parameter. The drilling operation is assessed based on the expression.

A method of drilling includes obtaining historical data for historical wells in a field, determining a set of drilling parameters, and determining a set of hole section sizes defining a wellbore geometry. For each combination of a parameter in the set of parameters and a hole section size in the set of hole section sizes, historical wells having average values of the parameter exceeding a threshold for the hole section size from the historical surface drilling data are selected. An expected output for each of a model to be trained by each of the selected historical wells is derived based on a rate of penetration while drilling. A final model is trained with the selected historical wells and expected outputs. An operating envelope is determined for each of the parameters in the set of parameters from the trained model. The operating envelopes may be used to guide drilling of a well in the field.

A method of drilling includes obtaining historical data for historical wells in a field, determining a set of drilling parameters, and determining a set of hole section sizes defining a wellbore geometry. For each combination of a parameter in the set of parameters and a hole section size in the set of hole section sizes, historical wells having average values of the parameter exceeding a threshold for the hole section size from the historical surface drilling data are selected. An expected output for each of a model to be trained by each of the selected historical wells is derived based on a rate of penetration while drilling. A final model is trained with the selected historical wells and expected outputs. An operating envelope is determined for each of the parameters in the set of parameters from the trained model. The operating envelopes may be used to guide drilling of a well in the field.

A lubrication system for a plunger/packing set of a fluid end has a lubricating fluid reservoir, a pump cooperative with the lubricating fluid reservoir so as to pump a lubricating fluid from the lubricating fluid reservoir toward the plunger/packing set, a primary pressure transducer cooperative with the pump so as to measure a pressure of the lubricating fluid exiting the fluid pump, a secondary pressure transducer cooperative with the fluid end so as to measure a pressure of the lubricating fluid exiting the plunger/packing set, and a controller connected to the second pressure transducer so as to obtain a representation of the pressure measured by the secondary pressure transducer.