US 11,781,422 B2
Horizontal directional drilling tool
Nicholas Peter Wallis, Worcestershire (GB); and Stuart Alfred Hall, Stroud (GB)
Assigned to GYROTECH LIMITED, (GB)
Filed by DV8 Technology Limited, Gloucestershire (GB)
Filed on Jul. 14, 2021, as Appl. No. 17/375,496.
Claims priority of application No. 2011183 (GB), filed on Jul. 20, 2020.
Prior Publication US 2022/0018243 A1, Jan. 20, 2022
Int. Cl. E21B 47/024 (2006.01); E21B 7/04 (2006.01)
CPC E21B 47/024 (2013.01) [E21B 7/046 (2013.01)] 18 Claims
OG exemplary drawing
 
18. A method for determining an azimuth of a drilling tool, the method comprising:
communicating, by a rate sensor, with a surface unit;
detecting, by a drill pipe extension detector, a process associated with extension of a drill pipe connecting the drilling tool to the surface unit, wherein the extension of the drill pipe comprises new sections of drill pipe being connected to one or more sections of drill pipe at surface as the borehole advances during drilling; and
transmitting, by a transmitter, rate sensor data collected during the extension of the drill pipe and indicative of a component of a rate of rotation of the earth, for determining the azimuth by gyrocompassing, to the surface unit, based on the detection of the process associated with extension of the drill pipe; and
wherein the process associated with the extension of the drill pipe comprises a loss of communication between the rate sensor and the surface unit.