US 11,053,740 B2
Downhole tool surfaces configured to reduce drag forces and erosion during exposure to fluid flow
Hau-Jiun Chen, Singapore (SG)
Assigned to Halliburton Energy Services, Inc., Houston, TX (US)
Appl. No. 15/531,078
Filed by Halliburton Energy Services, Inc., Houston, TX (US)
PCT Filed Dec. 30, 2014, PCT No. PCT/US2014/072754
§ 371(c)(1), (2) Date May 26, 2017,
PCT Pub. No. WO2016/108842, PCT Pub. Date Jul. 7, 2016.
Prior Publication US 2017/0342778 A1, Nov. 30, 2017
Int. Cl. E21B 10/43 (2006.01); E21B 4/02 (2006.01); F03B 13/02 (2006.01); E21B 17/10 (2006.01)
CPC E21B 10/43 (2013.01) [E21B 4/02 (2013.01); E21B 17/1078 (2013.01); F03B 13/02 (2013.01)] 12 Claims
OG exemplary drawing
 
1. A drilling system, comprising:
a drill string; and
a bottom hole assembly coupled to and disposed downhole from the drill string, the bottom hole assembly comprising:
a plurality of protrusions formed on a surface of the bottom hole assembly, each of the plurality of protrusions having a shape based on an anticipated fluid flow condition during a drilling operation;
a plurality of channels separating the plurality of protrusions; and
a plurality of nanotubes formed on the surface and oriented in an array that follows a contour of the surface, each of the plurality of nanotubes having a length between 10 nm and 1.5 μm and a diameter between 50 nm and 100 nm.