Turbopower turbodrills use a turbine motor, spun by injected fluid moving past vanes affixed to the rotor, for drilling vertical, horizontal and directional wells. The bit on a turbodrill spins much faster than on a conventional motor drill and although there is less torque, there is increased speed resulting in the ability to drill faster and easier through harder formations.
As part of our Drilling Performance approach, Halliburton can design the appropriate bit to be used in conjunction with turbodrill technology, essentially matching the formation and the drive mechanism. Turbodrills are used with fixed cutter bit applications (impregnated, diamond or PDC) to achieve optimum drilling efficiency.
Principal advantages of turbodrilling over other drilling methods
Performance. As a result of the high mechanical horsepower and speed delivered by the turbine, ROP can be maximized with PDC, diamond and impregnated bits. Sliding ROP (if required) is frequently equal to or even greater than rotating ROP when turbodrilling with a steerable turbine, so there is often no disadvantage in oriented drilling with a turbodrill, performance remains the same throughout the run.
Extended Run Length. The stabilized turbodrill / long gauge, box connection bit combination is a proven means of extending run length.
Steerability. Steerable turbodrills have an excellent track record for their ability to slide where other methods have proven difficult or unsuccessful. Bent housing turbines can also work in conjunction with drill string RPM.
Wellbore Quality. The turbodrill coupled with a long gauge bit combination produces a superior quality wellbore over other drilling methods which results in reduced torque and drag, improved electric logs, and often eliminates the need for wiper trips prior to running casing. This is particularly important when drilling extended reach wells with complex directional profiles. The positive displacement motor (PDM) power section moves in a eccentric circle creating lateral vibration which can lead to hole spiraling and poor quality of the wellbore, as opposed to the turbine which is an impulse motor with virtually no lateral vibration.
BHA/String Protection. The smooth impulse transmission of power from the turbodrill to the bit and the hydraulic cushioning effect against drill bit shocks, not only maximizes bit life but also gives added protection against vibration which increases BHA and string component life and minimizes drill string failure and fatigue.
Drilling Out Casing Shoe. Turbodrills have been used on many occasions to drill out the shoe track and complete a section of well to TD. Provided an appropriate bit is used in conjunction with the turbine the shoe track can be successfully drilled in a relatively short period of time without compromising the performance of the bit in the target formation. Of course, shoe track should be made from PDC drillable materials.