A system and method for calculating a path during drilling of a BHA between first and second survey points. The method includes calculating an amount of first incremental progress made by the BHA since the first survey point; calculating a first estimate of a first current location based on the first survey point and the amount of first incremental progress; causing at least one drilling parameter to be modified in order to alter a drilling direction of the BHA based on the first estimate; calculating an amount of second incremental progress made by the BHA; calculating a second estimate of the second current location based on the amount of second incremental progress and an aggregation of data received from the BHA, including data associated with the first survey point; and causing at least one drilling parameter to be modified in order to alter the drilling direction of the BHA.

A system and method for calculating a path during drilling of a BHA between first and second survey points. The method includes calculating an amount of first incremental progress made by the BHA since the first survey point; calculating a first estimate of a first current location based on the first survey point and the amount of first incremental progress; causing at least one drilling parameter to be modified in order to alter a drilling direction of the BHA based on the first estimate; calculating an amount of second incremental progress made by the BHA; calculating a second estimate of the second current location based on the amount of second incremental progress and an aggregation of data received from the BHA, including data associated with the first survey point; and causing at least one drilling parameter to be modified in order to alter the drilling direction of the BHA.

A disclosed borehole curvature logging system includes: a drill string having a bottomhole assembly (BHA) with sensors providing actual deformation and bending moment measurements as a function of BHA position at spaced-apart intervals on the BHA; a processing system that retrieves said actual measurements and responsively generates a log of borehole curvature; and a user interface that displays the borehole curvature log. The processing system implements a method that generates the log by: providing an estimated borehole trajectory; deriving predicted deformation and bending moment measurements based on the estimated borehole trajectory; determining an error between the predicted measurements and the actual measurements; updating the estimated borehole trajectory to reduce the error; repeating said deriving, determining, and updating to refine the estimated borehole trajectory; and converting the estimated borehole trajectory into a borehole curvature log.

Embodiments of a downhole drilling assembly generally include a rotatable lower drilling assembly, a rotatable upper drilling assembly, and a drill bit, wherein the upper drilling assembly contains a mud motor adapted for clockwise rotation of its stator and counter-clockwise rotation of its rotor, whereby the lower drilling assembly is rotatable in the opposite direction of the upper drilling assembly or maintainable in a non-rotating state. The apparatus further includes sensors adapted to continuously measure physical properties and/or drilling parameters and a mechanism for continuously transmitting information relating thereto to the surface.

Embodiments of a method for operating a downhole drilling assembly generally include continuously measuring physical properties and/or drilling parameters proximate the drill bit, continuously transmitting information relating thereto to the surface, and controlling rotation of a lower drilling assembly in a non-rotating state or in the opposite direction of an upper drilling assembly by varying drill string rotation.

Embodiments of a downhole drilling assembly generally include a rotatable lower drilling assembly, a rotatable upper drilling assembly, and a drill bit, wherein the upper drilling assembly contains a mud motor adapted for clockwise rotation of its stator and counter-clockwise rotation of its rotor, whereby the lower drilling assembly is rotatable in the opposite direction of the upper drilling assembly or maintainable in a non-rotating state. The apparatus further includes sensors adapted to continuously measure physical properties and/or drilling parameters and a mechanism for continuously transmitting information relating thereto to the surface.

Embodiments of a method for operating a downhole drilling assembly generally include continuously measuring physical properties and/or drilling parameters proximate the drill bit, continuously transmitting information relating thereto to the surface, and controlling rotation of a lower drilling assembly in a non-rotating state or in the opposite direction of an upper drilling assembly by varying drill string rotation.

A spindle with a mechanism for transferring axial force from an inner drive assembly to an outer drive assembly. The spindle's inner drive shaft is connected to an inner member of a dual-rod pipe by a drive rod having a sliding sleeve. The sleeve is fixed rotationally with the drive shaft, but not axially. When axial force drives the drive rod toward the drive member of the spindle, the sleeve contacts a stop member which is paired to the outer drive assembly. The stop member may be a pair of dowel pins. Axial force is thereby transferred from the inner member to the outer member, allowing such forces to be absorbed by the outer member's larger drive components.

A spindle with a mechanism for transferring axial force from an inner drive assembly to an outer drive assembly. The spindle's inner drive shaft is connected to an inner member of a dual-rod pipe by a drive rod having a sliding sleeve. The sleeve is fixed rotationally with the drive shaft, but not axially. When axial force drives the drive rod toward the drive member of the spindle, the sleeve contacts a stop member which is paired to the outer drive assembly. The stop member may be a pair of dowel pins. Axial force is thereby transferred from the inner member to the outer member, allowing such forces to be absorbed by the outer member's larger drive components.

The disclosure relates to embodiments of horizontal directional drilling equipment and methods for horizontal directional drilling techniques including a reamer head comprising a frustoconical body, wherein the frustoconical body defines a cavity configured to receive at least one bearing; and a plurality of teeth mounted to the frustoconical body. An imaginary apex of the frustoconical body is superimposed on the centerline of a reamer or reaming apparatus for reaming of an underground arcuate path. In another embodiment the reamer head is a progressive independently segmented reaming head. A plurality reaming heads are mounted to a reaming apparatus for reaming of an underground arcuate path.

A rotation brake for stopping rotation of a spindle assembly on a horizontal directional drill. The rotation brake comprises a brake lock that is actuated by a cylinder and spring to interact with a non-rotating brake cap and a rotating pinion, thereby stopping rotation of the pinion. The brake lock is removed from the pinion by applying pressurized fluid to a cylinder such that a cylinder rod moves the brake lock out of a cavity between the brake cap and the pinion. Upon removing fluid pressure from the cylinder, a compressed spring moves the brake lock back to into the cavity, preventing rotation.

An apparatus, a method for positioning a rock drilling, and a rock drilling rig is provided. The rock drilling rig includes a mobile drilling platform and a drilling mast connected to the drilling platform. The drilling platform is levelled vertically before initiating drilling. The apparatus determines the needed vertical levelling requirement. The levelling causes displacement of a drilling tool line passing through a drilling tool. The apparatus estimates the displacement and provides aid for the operator to position the drilling platform in order to compensate for the estimated displacement distance.