Abstract: A float valve assembly is configured to be positioned within in a central bore of a tubular string disposed in a wellbore drilled into a subterranean zone. The float valve assembly includes a valve main body and a plunger, and the plunger is biased by a spring towards a closed position and is configured to open in response to a fluid pressure in a downhole direction. The surface of the plunger main body includes a plurality of substantially flat lateral faces forming a pyramid. A hydrophilic nano-coating comprising particles with sizes of between 1 and 100 nanometers is disposed on at least a portion of the surface of the plunger main body.

Abstract: A wellbore drill bit includes a body that defines an inner volume and includes a top sub-assembly, and a plurality of cutting cones along a longitudinal axis of the body. The wellbore drill bit includes a chamber positioned in the inner volume of the body to form an annulus between the chamber and the body; a first set of nozzles positioned in the plurality of cutting cones, each nozzle of the first set of nozzles including a fluid entry that is fluidly coupled to a primary drilling fluid flow path, and a fluid exit oriented toward the second longitudinal end of the body; and a second set of nozzles positioned in the body. Each nozzle of the second set of nozzles includes a fluid entry that is fluidly coupled to the annulus, and a fluid exit oriented toward the first longitudinal end of the body.

Abstract: A wellbore drill bit includes a body that defines an inner volume and includes a top sub-assembly and is configured to couple to a drilling string, and a plurality of cutting cones along a longitudinal axis of the body. The wellbore drill bit includes a chamber positioned in the inner volume of the body to form an annulus between the chamber and the body; a first set of nozzles positioned in the plurality of cutting cones, each nozzle of the first set of nozzles including a fluid entry that is fluidly coupled to a primary drilling fluid flow path, and a fluid exit oriented toward the second longitudinal end of the body; and a second set of nozzles positioned in the body. Each nozzle of the second set of nozzles includes a fluid entry that is fluidly coupled to the annulus, and a fluid exit oriented toward the first longitudinal end of the body.