Air and mud control system for underbalanced drilling
Annulus pressure control drilling systems and methods
Apparatus and method to reduce fluid pressure in a wellbore
Apparatus and method to reduce fluid pressure in a wellbore
Apparatus and method to reduce fluid pressure in a wellbore
Apparatus and method to reduce fluid pressure in a wellbore
Closed-loop control of hydraulic pressure in a downhole...
Closed-loop physical caliper measurements and directional...
Device for remote actuating equipment comprising delay means
Devices and methods for power control in horizontal...
Downhole tool including pressure intensifier for drilling...
Drill pipes and casings utilizing multi-conduit tubulars
Drill string shutoff valve
Drilling system
Enhanced computer control of in-situ drilling system
Hydraulic drilling apparatus and method
Hydrojet drilling means
Method and apparatus for directly controlling pressure and...
Method and arrangement for controlling feed in rock drilling
Method and system for circulating a gas bubble from a well