US 11,773,676 B2
Whipstock assembly
William Brown-Kerr, Aboyne (GB); and Andrew John Watson, Aberdeen (GB)
Assigned to OILTOOLSTEQ LTD, Aberdeen (GB)
Appl. No. 17/255,885
Filed by OILTOOLSTEQ LTD, Aberdeen (GB)
PCT Filed Jun. 28, 2019, PCT No. PCT/GB2019/051835
§ 371(c)(1), (2) Date Dec. 23, 2020,
PCT Pub. No. WO2020/002936, PCT Pub. Date Jan. 2, 2020.
Claims priority of application No. 1810604 (GB), filed on Jun. 28, 2018.
Prior Publication US 2021/0372219 A1, Dec. 2, 2021
Int. Cl. E21B 23/00 (2006.01); E21B 7/06 (2006.01); E21B 29/06 (2006.01)
CPC E21B 29/06 (2013.01) [E21B 7/061 (2013.01); E21B 23/00 (2013.01)] 18 Claims
OG exemplary drawing
 
1. A whipstock assembly for use in deviating a wellbore of a well, the whipstock assembly comprising:
a whipstock having an inclined deflection surface;
a milling assembly comprising a mill for milling a window in a wall of the wellbore and forming a rathole extending from the wellbore, wherein the milling assembly is defined by the mill, which is a lead mill, a further mill and a structure extending between the lead mill and the further mill;
a releasable joint by which the milling assembly is releasably connected to the whipstock, so that the milling assembly can be separated from the whipstock within the wellbore and subsequently deflected towards the wall of the wellbore by the inclined deflection surface of the whipstock;
at least one sensor provided in the milling assembly, for measuring at least one parameter of the rathole, the at least one parameter relating to a trajectory of the rathole;
and
a communication device associated with the at least one sensor, for communicating data relating to the at least one parameter to an operator of the milling assembly,
wherein the at least one sensor and the communication device are mounted within the releasable joint.