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.

A risk assessment-based design method for a deep complex formation wellbore structure includes: (1) preliminarily determining casing layers and setting depths; (2) calculating to obtain the risk coefficients of each layer of casing; (3) analyzing and coordinating, according to the principle that a shallow casing shares more risks and a deep casing shares less risks, the risks of each layer of casing: determining whether the risk coefficients of each layer of casing are greater than a safety threshold value K; checking the setting depth: if the safety coefficient of an ith-layer casing satisfies R.sub.Ni>K, selecting a casing layer with the minimum safety coefficient from upper casing layers, and deepening the setting depth h of the casing layer; and (4) repeating the steps (2) to (3) until the casing risk coefficients of each layer of casing are less than the safety threshold value K.

A risk assessment-based design method for a deep complex formation wellbore structure includes: (1) preliminarily determining casing layers and setting depths; (2) calculating to obtain the risk coefficients of each layer of casing; (3) analyzing and coordinating, according to the principle that a shallow casing shares more risks and a deep casing shares less risks, the risks of each layer of casing: determining whether the risk coefficients of each layer of casing are greater than a safety threshold value K; checking the setting depth: if the safety coefficient of an ith-layer casing satisfies R.sub.Ni>K, selecting a casing layer with the minimum safety coefficient from upper casing layers, and deepening the setting depth h of the casing layer; and (4) repeating the steps (2) to (3) until the casing risk coefficients of each layer of casing are less than the safety threshold value K.

A managed pressure drilling (MPD) manifold has one or more valves that are operable by one or more actuators configured to synchronize the opening of one or more passageways in the valves with the closing of one or more of the other passageways in the valves, in order to minimize the likelihood of error and reduce response time. The valves are configured to transition smoothly between positions without fully blocking fluid flow in the manifold while changing the flow direction. The synchronization may be achieved mechanically, electrically, hydraulic, and/or pneumatically. The actuators may be remotely controlled by a control unit having a processor and control logic software, based on data collected by one or more sensors in the MPD manifold. The positions of the valves of the MPD manifold may be automatically adjusted by the control unit via the actuators.

A managed pressure drilling (MPD) manifold has one or more valves that are operable by one or more actuators configured to synchronize the opening of one or more passageways in the valves with the closing of one or more of the other passageways in the valves, in order to minimize the likelihood of error and reduce response time. The valves are configured to transition smoothly between positions without fully blocking fluid flow in the manifold while changing the flow direction. The synchronization may be achieved mechanically, electrically, hydraulic, and/or pneumatically. The actuators may be remotely controlled by a control unit having a processor and control logic software, based on data collected by one or more sensors in the MPD manifold. The positions of the valves of the MPD manifold may be automatically adjusted by the control unit via the actuators.

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.

There is described a computer-implemented method of controlling a drilling operation. In particular, there is described a computer-implemented method of determining that a differential pressure is in an oscillating state. In response to determining that the differential pressure is in the oscillating state, a weight on bit setpoint is decreased so as to decrease the differential pressure. There is also described a computer-implemented method of determining a difference between a differential pressure and a target differential pressure. The target differential pressure is less than a differential pressure limit. A weight on bit setpoint is adjusted as a function of the difference between the differential pressure and the target differential pressure so as to adjust the differential pressure and thereby reduce the difference between the differential pressure and the target differential pressure.

There is described a computer-implemented method of controlling a drilling operation. In particular, there is described a computer-implemented method of determining that a differential pressure is in an oscillating state. In response to determining that the differential pressure is in the oscillating state, a weight on bit setpoint is decreased so as to decrease the differential pressure. There is also described a computer-implemented method of determining a difference between a differential pressure and a target differential pressure. The target differential pressure is less than a differential pressure limit. A weight on bit setpoint is adjusted as a function of the difference between the differential pressure and the target differential pressure so as to adjust the differential pressure and thereby reduce the difference between the differential pressure and the target differential pressure.

There are described methods, systems, and techniques for performing automated drilling of a well bore. The well bore is drilled according to one or more drilling parameter targets associated with one or more corresponding drilling parameters. A controlling drilling parameter of the one or more drilling parameters is determined to be outside a threshold window. In response to determining that a stringer has been encountered, one or more controlled drilling parameter targets of the one or more drilling parameter targets are updated. The controlled drilling parameter targets comprise a revolutions per minute (RPM) target and weight-on-bit (WOB) target.