Long gauge roller vane drilling motor

Machine operating according to the Moineau-Principle for the...

Mandrel and bearing assembly for downhole drilling motor

Mechanically actuated fluid control device for downhole fluid mo

Mechanically nutating drill driven by orbiting mass oscillator

Method and apparatus for advancing tethers

Method and apparatus for drilling boreholes in earth formations

Method and apparatus for drilling boreholes in earth...

Method and apparatus for drilling in permafrost and the like

Method and apparatus for operations in underground subsea...

Method and apparatus for sinking a cased borehole for producing

Milling machine for cutting trenches

Motor shaft security apparatus

Multistage, downhole, turbo-powered intensifier for drilling pet

Oscillating friction ring assembly for applying axial thrust to

Percussion tool

Percussive air hammer and core bit apparatus

Peristaltic down-hole drilling motor

Pipe-driving apparatus

Pneumatic hammer-auger earth boring apparatus