The pure mechanical well deviation wireless measure-while-drilling and mud pulse generation device includes an outer cylinder and an inner cylinder coaxially arranged inside the outer cylinder; an inner flow channel is formed inside the inner cylinder, and an outer flow channel is formed between the inner cylinder and the outer cylinder; a flow control valve and a hydraulic turbine are arranged in the inner flow channel, and the flow control valve is located at an upstream section of the hydraulic turbine. The device further includes a signal generation base and a rotary stopper. An overflow hole is formed on the signal generation base and arranged in the annular outer flow channel, and the rotary stopper can periodically shield the overflow hole. The inclinometer includes the pure mechanical well deviation wireless measure-while-drilling and mud pulse generation device, an inclinometer outer cylinder and an eccentric rotary column.

The pure mechanical well deviation wireless measure-while-drilling and mud pulse generation device includes an outer cylinder and an inner cylinder coaxially arranged inside the outer cylinder; an inner flow channel is formed inside the inner cylinder, and an outer flow channel is formed between the inner cylinder and the outer cylinder; a flow control valve and a hydraulic turbine are arranged in the inner flow channel, and the flow control valve is located at an upstream section of the hydraulic turbine. The device further includes a signal generation base and a rotary stopper. An overflow hole is formed on the signal generation base and arranged in the annular outer flow channel, and the rotary stopper can periodically shield the overflow hole. The inclinometer includes the pure mechanical well deviation wireless measure-while-drilling and mud pulse generation device, an inclinometer outer cylinder and an eccentric rotary column.

A method for causing a desired drilling direction of a steerable subterranean drill in consideration of a contemporaneously detected formation tendency force acting on a drill bit of the steerable subterranean drill. The method includes detecting, utilizing a steering direction setting device, a direction and magnitude of a formation tendency force acting on the drill bit of the steerable subterranean drill. Further the steering direction setting device is configured to contemporaneously cause the drill bit of the steerable subterranean drill to drill in the desired direction, counteracting the formation tendency force based on the detected direction and magnitude of the formation tendency force acting on the drill bit.

A gyroscope assembly is maintained in a park position during drilling activities. In the park position, a sensitive axis of a gyroscope in the gyroscope assembly is perpendicular or approximately perpendicular to a longitudinal axis of a downhole tool. Maintaining the park position during drilling activities reduces the drift bias caused by overloading the input signal of the gyroscope due to rotation of the downhole tool.

A signal method may include obtaining a first set of signal measurements, processing the first set of signal measurements into a phase reference obtaining a second set of signal measurements, the second set of signal measurements varying as a function of the phase reference, detecting an item of interest using the second set of signal measurements and the phase reference, and using the item of interest.

An inspection system to measure the condition of at least a wall of a ground opening, the inspection system having a head unit for lowering into a borehole during a data collection phase wherein at least one set of test data is collected concerning one or more physical characteristics of the borehole during the data collection phase, the head unit having an internal measurement system and a sensor arrangement with a plurality of sensors facing radially outwardly of a head axis that is generally parallel to at least a portion of a borehole axis, the plurality of sensors allowing the head unit to be moved during the data collection phase without rotation about the head axis, the plurality of sensors at least partially producing the at least one set of test data collected during the data collection phase.

A navigation device for surveying and directing a borehole comprises: a first gyro including a first sensitive axis and a second sensitive axis; a second gyro including at least a third sensitive axis; and a driving unit configured to orient the second gyro in a first mode in a first position in which an earth acceleration dependent error on the second gyro is insignificant and to orient the second gyro in a second mode in a second position in which the third sensitive axis is perpendicular to the first sensitive axis and perpendicular to the second sensitive axis.

A gyroscope assembly is maintained in a park position during drilling activities. In the park position, a sensitive axis of a gyroscope in the gyroscope assembly is perpendicular or approximately perpendicular to a longitudinal axis of a downhole tool. Maintaining the park position during drilling activities reduces the drift bias caused by overloading the input signal of the gyroscope due to rotation of the downhole tool.

A signal method may include obtaining a first set of signal measurements, processing the first set of signal measurements into a phase reference obtaining a second set of signal measurements, the second set of signal measurements varying as a function of the phase reference, detecting an item of interest using the second set of signal measurements and the phase reference, and using the item of interest.

Disclosed are systems and methods of orienting wellbore tubulars using gravity. Some disclosed orientation indicating devices include a housing defining a first flow channel and being arrangeable within a wellbore tubular, an orientor movably arranged within the housing and defining a second flow channel in fluid communication with the first flow channel, and an eccentric weight arranged within the orientor and having a center of mass radially offset from a rotational axis of the orientor, the eccentric weight being configured to maintain the orientor pointing in one direction as the housing and the wellbore tubular are rotated, wherein, as the housing rotates, the first and second flow channels become progressively aligned or misaligned.