An apparatus and method for measuring position and magnitude of downhole mechanical friction. The apparatus comprises sensors that reside along, or in-line with, a section of equipment that is installed or removed from a wellbore. The sensing device is configured measure relative to the wellbore during a work-over or other well intervention procedures where said section of equipment (tubing, rods, drill pipe, etc.) is installed in, or removed from, the wellbore. Recorded measurements are then processed to correct for dynamic forces to provide a measure of friction through the portions of the wellbore where said equipment travels. The sensing can be done near the source of friction, or at some distance through a mechanical connection. A method for determining depth and magnitude of downhole friction is also provided. Additionally, a method for applying the map of wellbore friction to the design and analysis of a rod actuated pump is presented.

An apparatus and method for measuring position and magnitude of downhole mechanical friction. The apparatus comprises sensors that reside along, or in-line with, a section of equipment that is installed or removed from a wellbore. The sensing device is configured measure relative to the wellbore during a work-over or other well intervention procedures where said section of equipment (tubing, rods, drill pipe, etc.) is installed in, or removed from, the wellbore. Recorded measurements are then processed to correct for dynamic forces to provide a measure of friction through the portions of the wellbore where said equipment travels. The sensing can be done near the source of friction, or at some distance through a mechanical connection. A method for determining depth and magnitude of downhole friction is also provided. Additionally, a method for applying the map of wellbore friction to the design and analysis of a rod actuated pump is presented.

A method for processing friction data for vehicle tires on road segments, implemented by a processing system including at least one computer and an interface for remote communication with a plurality of vehicles, the method including: acquiring, from the plurality of vehicles, friction data for tires of the vehicles on a plurality of road segments, each friction datum including at least: a maximum coefficient of friction available to the vehicle on the road segment, and information relating to the road segment; establishing, for each road segment, a distribution of the friction data obtained from the plurality of vehicles for the road segment; and determining a plurality of road types, each road type comprising a set of road segments, from a measurement of similarity between the distributions of friction data obtained for each road segment.

A method for processing friction data for vehicle tires on road segments, implemented by a processing system including at least one computer and an interface for remote communication with a plurality of vehicles, the method including: acquiring, from the plurality of vehicles, friction data for tires of the vehicles on a plurality of road segments, each friction datum including at least: a maximum coefficient of friction available to the vehicle on the road segment, and information relating to the road segment; establishing, for each road segment, a distribution of the friction data obtained from the plurality of vehicles for the road segment; and determining a plurality of road types, each road type comprising a set of road segments, from a measurement of similarity between the distributions of friction data obtained for each road segment.

The present disclosure relates to the drilling of oil wells and more particularly to a testing tool, a testing assembly and method for use in measuring selected rock mechanics characteristics downhole.

The present disclosure relates to the drilling of oil wells and more particularly to a testing tool, a testing assembly and method for use in measuring selected rock mechanics characteristics downhole.

A method for friction coefficient determination on elastically connected subsystems, in which an overall system includes multiple subsystems and at least two subsystems are connected to one another by an elastic connection. The elastic connection has at least one static friction state and a sliding friction state for prescribed external state variables, in which the overall system is excited with a vibration having a variable excitation amplitude at a defined excitation frequency. The excitation amplitude is varied, in which a phase difference between the vibration and a measured reaction torque together with the excitation amplitude are recorded as a function of time, in which no phase difference occurs in the static friction state and a phase difference of 180° occurs in the sliding friction state. In a first step, the excitation amplitude is increased until a transition in the phase difference from 0° to 180° indicates the transition from the static friction state to the sliding friction state.

A method for friction coefficient determination on elastically connected subsystems, in which an overall system includes multiple subsystems and at least two subsystems are connected to one another by an elastic connection. The elastic connection has at least one static friction state and a sliding friction state for prescribed external state variables, in which the overall system is excited with a vibration having a variable excitation amplitude at a defined excitation frequency. The excitation amplitude is varied, in which a phase difference between the vibration and a measured reaction torque together with the excitation amplitude are recorded as a function of time, in which no phase difference occurs in the static friction state and a phase difference of 180° occurs in the sliding friction state. In a first step, the excitation amplitude is increased until a transition in the phase difference from 0° to 180° indicates the transition from the static friction state to the sliding friction state.

A lubricity tester unit may comprise a housing, a shaft, wherein a first end of the shaft is disposed at a first end of the housing, wherein the shaft extends through housing along a central axis of the housing, and an encoder, wherein the encoder is disposed on an internal wall of the housing, wherein the shaft is disposed through a hole in the encoder, wherein the encoder is an optical encoder configured to measure angular position of the shaft. The lubricity tester unit may further comprise rotating rings, wherein the rotating rings are coupled to a second end of the shaft, a friction inducing surface, wherein the friction inducing surface is disposed around the rotating rings, a first sensor, wherein the first sensor is disposed through the housing, and a second sensor, wherein the second sensor is disposed through the housing.

A lubricity tester unit may comprise a housing, a shaft, wherein a first end of the shaft is disposed at a first end of the housing, wherein the shaft extends through housing along a central axis of the housing, and an encoder, wherein the encoder is disposed on an internal wall of the housing, wherein the shaft is disposed through a hole in the encoder, wherein the encoder is an optical encoder configured to measure angular position of the shaft. The lubricity tester unit may further comprise rotating rings, wherein the rotating rings are coupled to a second end of the shaft, a friction inducing surface, wherein the friction inducing surface is disposed around the rotating rings, a first sensor, wherein the first sensor is disposed through the housing, and a second sensor, wherein the second sensor is disposed through the housing.