A method and system of adjusting near-bit weight on a drill bit in a drill string having a bottom hole assembly located at an end of a drill pipe, an anti-stall device near the bottom hole assembly, surface sensing and control equipment and a downhole-to-surface communication system, the anti-stall device measuring downhole performance criteria and evaluation of the measured downhole performance criteria, comprising the steps of measuring at least one downhole performance criteria by the anti-stall device; evaluating the measured downhole performance criteria in substantially real time by the anti-stall device; adjusting weight on the drill bit by the anti-stall device based on the evaluation by the anti-stall device; and communicating the adjustment to weight on the drill bit to the surface sensing and control equipment by the downhole-to-surface communication system for further adjustment of weight on the drill bit.

Described are systems and methods for evaluating the leak safety of threaded connections in well tubulars. A method, for example, includes assessing leak risk according to a Leak Criterion with Thread Shear. The Leak Criterion with Thread Shear is a function of the conditions relative to a pin-box interface radius and includes two constants: a Thread Modulus (alpha) and a Makeup Leak Resistance (beta). The leak risk is evaluated at the pin-box interface and is a function of differential pressure, effective stress, and shear stress. Lab tests conducted under known conditions are described for calculating the constants, alpha and beta, which are independent of extrinsic states or conditions.

Described are systems and methods for evaluating the leak safety of threaded connections in well tubulars. A method, for example, includes assessing leak risk according to a Leak Criterion with Thread Shear. The Leak Criterion with Thread Shear is a function of the conditions relative to a pin-box interface radius and includes two constants: a Thread Modulus (alpha) and a Makeup Leak Resistance (beta). The leak risk is evaluated at the pin-box interface and is a function of differential pressure, effective stress, and shear stress. Lab tests conducted under known conditions are described for calculating the constants, alpha and beta, which are independent of extrinsic states or conditions.

A system for inspecting flexible pipelines comprises a data analyzer, a data collector and an ultrasonic transducer. Further, the ultrasonic transducer is adapted to propagate shear wave into the annulus of the flexible pipeline. The data collector further comprises a data store and a communicator. Further, the system is capable of differentiating flooding and non-flooding condition of the annulus of the flexible pipeline which is subjected to high pressure. Using the system, an indicator of a flooded or non-flooded condition within the flexible pipeline may be calculated using transmitted and detected reflective waves or the lack of detected reflective waves.

A system for inspecting flexible pipelines comprises a data analyzer, a data collector and an ultrasonic transducer. Further, the ultrasonic transducer is adapted to propagate shear wave into the annulus of the flexible pipeline. The data collector further comprises a data store and a communicator. Further, the system is capable of differentiating flooding and non-flooding condition of the annulus of the flexible pipeline which is subjected to high pressure. Using the system, an indicator of a flooded or non-flooded condition within the flexible pipeline may be calculated using transmitted and detected reflective waves or the lack of detected reflective waves.

Disclosed are methods, systems, and computer-readable medium to perform operations including: receiving real-time drilling data of a drilling operation of drilling a wellbore; using the drilling data to calculate at least one indicator of a borehole cleaning efficiency of the drilling operation; detecting, based on the least one indicator of the borehole cleaning efficiency, a drilling problem with the drilling operation; determining a corrective action to avoid or mitigate the drilling problem; and performing the corrective action to avoid or mitigate the drilling problem.

Disclosed are methods, systems, and computer-readable medium to perform operations including: receiving real-time drilling data of a drilling operation of drilling a wellbore; using the drilling data to calculate at least one indicator of a borehole cleaning efficiency of the drilling operation; detecting, based on the least one indicator of the borehole cleaning efficiency, a drilling problem with the drilling operation; determining a corrective action to avoid or mitigate the drilling problem; and performing the corrective action to avoid or mitigate the drilling problem.

A method comprises determining a value of at least one oppositional force for a drillstring at multiple depths in the wellbore, determining a value of hook load for the drillstring at the multiple depths based on the value of the at least one opposition force at the multiple depths, and determining a calibrated drillstring weight based on a change in the value of the hook load over the multiple depths of the wellbore. The change in the value of the hook load can be determined based on a change in a measured hook load and/or a change in an estimated hook load. From the calibrated drillstring weight, an adjusted estimated hook load can be determined.

A method comprises determining a value of at least one oppositional force for a drillstring at multiple depths in the wellbore, determining a value of hook load for the drillstring at the multiple depths based on the value of the at least one opposition force at the multiple depths, and determining a calibrated drillstring weight based on a change in the value of the hook load over the multiple depths of the wellbore. The change in the value of the hook load can be determined based on a change in a measured hook load and/or a change in an estimated hook load. From the calibrated drillstring weight, an adjusted estimated hook load can be determined.

A method comprises determining a value of at least one oppositional force for a drillstring at multiple depths in the wellbore, determining a value of a drag force for the drillstring at the multiple depths, determining a value of hook load for the drillstring at the multiple depths based on the value of the at least one opposition force and the value of the drag force at the multiple depths, and determining a calibrated drillstring weight based on a change in the value of the hook load over the multiple depths. From the calibrated drillstring weight, an adjusted estimated hook load can be determined. The drag force can be calculated based on a drag per centralizer and the number of centralizers in the wellbore. A centralizer friction factor can be determined and used to calibrate the value of the drag per centralizer.